Article

Prevalence and correlates of Vitamin D deficiency in US adults

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Abstract

Mounting evidence suggests that vitamin D deficiency could be linked to several chronic diseases, including cardiovascular disease and cancer. The purpose of this study was to examine the prevalence of vitamin D deficiency and its correlates to test the hypothesis that vitamin D deficiency was common in the US population, especially in certain minority groups. The National Health and Nutrition Examination Survey 2005 to 2006 data were analyzed for vitamin D levels in adult participants (N = 4495). Vitamin D deficiency was defined as a serum 25-hydroxyvitamin D concentrations ≤20 ng/mL (50 nmol/L). The overall prevalence rate of vitamin D deficiency was 41.6%, with the highest rate seen in blacks (82.1%), followed by Hispanics (69.2%). Vitamin D deficiency was significantly more common among those who had no college education, were obese, with a poor health status, hypertension, low high-density lipoprotein cholesterol level, or not consuming milk daily (all P < .001). Multivariate analyses showed that being from a non-white race, not college educated, obese, having low high-density lipoprotein cholesterol, poor health, and no daily milk consumption were all significantly, independently associated with vitamin D deficiency (all P < .05). In summary, vitamin D deficiency was common in the US population, especially among blacks and Hispanics. Given that vitamin D deficiency is linked to some of the important risk factors of leading causes of death in the United States, it is important that health professionals are aware of this connection and offer dietary and other intervention strategies to correct vitamin D deficiency, especially in minority groups.

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... 30 A challenge in studying the relationship between vitamin D deficiency and COVID-19 outcomes is that risk factors for vitamin D deficiency are also associated with COVID-19 disease severity (e.g., obesity, medical comorbidities) as well as social determinants of health (e.g., non-Whiterace/ethnicity and poverty). 9,12,15,31 Some prior COVID-19-related observational studies and trials have failed to fully adjust for potential confounding, particularly race/ethnicity, owing to the lack of diversity in the populations studied. 19,24,25 Because of the controversy surrounding vitamin D supplementation, in July 2020, the US National Institutes of Health concluded "there are insufficient data to recommend either for or against the use of vitamin D for the prevention or treatment of COVID-19." ...
... 12,40 Additional comorbidities associated with both COVID-19 severity and vitamin D deficiency were included, namely obesity (body mass index (BMI) as a continuous variable in kilograms/meters 2 (kg/m 2 )), smoking, COPD, obstructive sleep apnea, CVD including hypertension, cancer, diabetes, chronic kidney disease (CKD), liver disease, human immunodeficiency virus (HIV), drug dependence, and alcohol dependence. 15,31 The International Classification of Diseases, Tenth Edition (ICD-10) codes denoting each condition associated with VA outpatient and inpatient encounters that occurred within 2 years preceding the index SARS-CoV-2 test were included in these analyses. 41 ...
... In Black and other non-White individuals, darker skin pigmentation blocks ultraviolet light; thus, more solar radiation may be required to produce similar concentrations of 25(OH)D, although the etiology of low 25(OH)D in non-White individuals remains controversial. 12,15,47,48 In addition, stay-at-home orders or quarantining related to COVID-19 may have resulted in even less sun exposure, putting some individuals at greater risk for vitamin D deficiency. 49 Furthermore, ad hoc analyses of the larger cohort of 71,175 with positive SARS-CoV-2 tests (Figure 1) revealed that patients who were Caucasian, older, female, and had a variety of chronic health conditions including CVD, COPD, and cancer were significantly more likely to have been tested for 25(OH)D in the 15-90 days prior to their index positive SARS-CoV-2 test (Appendix Table 4). ...
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Background The relationship between vitamin D status and COVID-19-related clinical outcomes is controversial. Prior studies have been conducted in smaller, single-site, or homogeneous populations limiting adjustments for social determinants of health (race/ethnicity and poverty) common to both vitamin D deficiency and COVID-19 outcomes. Objective To evaluate the dose-response relationship between continuous 25(OH)D and risk for COVID-19-related hospitalization and mortality after adjusting for covariates associated with both vitamin D deficiency and COVID-19 outcomes. Design Retrospective cohort study. Patients Veteran patients receiving care in US Department of Veteran Affairs (VA) health care facilities with a positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test and a blood 25(OH)D test between February 20, 2020, and November 8, 2020, followed for up to 60 days. Main Measures Exposure was blood 25(OH)D concentration ascertained closest to and within 15 to 90 days preceding an index positive SARS-CoV-2 test. Co-primary study outcomes were COVID-19-related inpatient hospitalization requiring airborne, droplet, contact, or other isolation and mortality ascertained within 60 days of an index positive SARS-CoV-2 test. Key Results Of 4,599 veterans with a positive SARS-CoV-2 test, vitamin D deficiency (< 20 ng/mL) was identified in 665 (14.5%); 964 (21.0%) were hospitalized; and 340 (7.4%) died. After adjusting for all covariates, including race/ethnicity and poverty, there was a significant independent inverse dose-response relationship between increasing continuous 25(OH)D concentrations (from 15 to 60 ng/mL) and decreasing probability of COVID-19-related hospitalization (from 24.1 to 18.7%, p =0.009) and mortality (from 10.4 to 5.7%, p =0.001). In modeling 25(OH)D as a log-transformed continuous variable, the greatest risk for hospitalization and death was observed at lower 25(OH)D concentrations. Conclusions Continuous blood 25(OH)D concentrations are independently associated with COVID-19-related hospitalization and mortality in an inverse dose-response relationship in this large racially and ethnically diverse cohort of VA patients. Randomized controlled trials are needed to evaluate the impact of vitamin D supplementation on COVID-19-related outcomes.
... In this publication, we will demonstrate that vitamin D3 deficiency, which is a well-documented worldwide problem [13][14][15][16][17][18][19]179], is one of the main reasons for severe courses of SARS CoV 2 -- ...
... infections. The fatality rates correlate well with the findings that elderly people, black people and people with comorbidities show very low vitamin D3 levels [16,[20][21][22]. Additionally, with only a few exceptions, we are facing the highest infection rates in the winter months and in northern countries, which are known to suffer from low vitamin D3 levels due to low endogenous sun-triggered vitamin D3 ...
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Background Much research shows that blood calcidiol (25(OH)D3) levels correlate strongly with SARS-CoV-2 infection severity. There is open discussion regarding whether low D3 is caused by the infection or if deficiency negatively affects immune defense. The aim of this study was to collect further evidence on this topic. Methods Systematic literature search was performed to identify retrospective cohort as well as clinical studies on COVID-19 mortality rates vs. D3 blood levels. Mortality rates from clinical studies were corrected for age, sex and diabetes. Data was analyzed using correlation and linear regression. Results One population study and seven clinical studies were identified, which reported D3 blood levels pre-infection or on the day of hospital admission. They independently showed a negative Pearson correlation of D3 levels and mortality risk (r(17)=-.4154, p=.0770/r(13)=-.4886, p=.0646). For the combined data, median (IQR) D3 levels were 23.2 ng/ml (17.4 – 26.8), and a significant Pearson correlation was observed (r(32)=-.3989, p=.0194). Regression suggested a theoretical point of zero mortality at approximately 50 ng/ml D3. Conclusions The two datasets provide strong evidence that low D3 is a predictor rather than a side effect of the infection. Despite ongoing vaccinations, we recommend raising serum 25(OH)D levels to above 50 ng/ml to prevent or mitigate new outbreaks due to escape mutations or decreasing antibody activity.
... In this publication, we will demonstrate that vitamin D3 deficiency, which is a well-documented worldwide problem [13][14][15][16][17][18][19][20], is one of the main reasons for severe courses of SARS-CoV-2 infections. The fatality rates correlate well with the findings that elderly people, black people, and people with comorbidities show very low vitamin D3 levels [16,[21][22][23]. ...
... In this publication, we will demonstrate that vitamin D3 deficiency, which is a well-documented worldwide problem [13][14][15][16][17][18][19][20], is one of the main reasons for severe courses of SARS-CoV-2 infections. The fatality rates correlate well with the findings that elderly people, black people, and people with comorbidities show very low vitamin D3 levels [16,[21][22][23]. Additionally, with only a few exceptions, we are facing the highest infection rates in the winter months and in northern countries, which are known to suffer from low vitamin D3 levels due to low endogenous sun-triggered vitamin D3 synthesis [24][25][26][27]. ...
Article
Full-text available
Background: Much research shows that blood calcidiol (25(OH)D3) levels correlate strongly with SARS-CoV-2 infection severity. There is open discussion regarding whether low D3 is caused by the infection or if deficiency negatively affects immune defense. The aim of this study was to collect further evidence on this topic. Methods: Systematic literature search was performed to identify retrospective cohort as well as clinical studies on COVID-19 mortality rates versus D3 blood levels. Mortality rates from clinical studies were corrected for age, sex, and diabetes. Data were analyzed using correlation and linear regression. Results: One population study and seven clinical studies were identified, which reported D3 blood levels preinfection or on the day of hospital admission. The two independent datasets showed a negative Pearson correlation of D3 levels and mortality risk (r(17) = -0.4154, p = 0.0770/r(13) = -0.4886, p = 0.0646). For the combined data, median (IQR) D3 levels were 23.2 ng/mL (17.4-26.8), and a significant Pearson correlation was observed (r(32) = -0.3989, p = 0.0194). Regression suggested a theoretical point of zero mortality at approximately 50 ng/mL D3. Conclusions: The datasets provide strong evidence that low D3 is a predictor rather than just a side effect of the infection. Despite ongoing vaccinations, we recommend raising serum 25(OH)D levels to above 50 ng/mL to prevent or mitigate new outbreaks due to escape mutations or decreasing antibody activity.
... and male were 150 (27.4%). In Vietnam, a cross-sectional study was done where the mean age of men was 43.8 year and mean age of women was 47.7 year [13], in Hong Kong revealed the mean age of the respondents was 69 ± 9 years [16], another study found mean ± SD was 10.8 ± 4.3 ranging from 1.6 to17.5 where male 69 (54%), female 59 (46%) [19]. Vitamin D3D2 status of the respondents of presents study was enrolled (in Table 2), where most of the respondents 385(70.4%) ...
... This study defined vitamin D deficiency as a serum 25-hydroxyvitamin D concentrations which was ≤20 ng/mL or 50 nmol/L. Vitamin D deficiency was found statistically more common among the obese people with hypertension, with low high-density lipoprotein, poor health status, cholesterol level, or not consuming milk daily which was an abundant source calcium necessary for bone growth [16]. Another study in Korea found that vitamin D in sufficiency were mostly determined to those who work for indoor occupation. ...
Article
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Introduction: Vitamin D is a fat-soluble vitamin that can be found naturally in a few foods, added to others, and taken as a supplement. When ultraviolet (UV) photons from the sun strike the skin and trigger vitamin D synthesis. Aim of the study: The aim of the study was to evaluate Vitamin D3D2 status and its associated factors of an urban tertiary care of Bangladesh. Methods: The study was conducted at the Bangladesh Institute of Research and Rehabilitation in Diabetes (BIRDEM), to evaluate the Vitamin D3D2 status and its associated factors of an urban tertiary care of Bangladesh. A total of 547 cases were chosen by random sampling, with Vitamin D3D2 status from July 2013 to June 2018. The results were statistically analyzed with Statistical Packages for Social Sciences (SPSS-24). Results: Most of the respondent in this study 329 (59.9%) belonged to the age group of 31-60, mean ± SD was 41.4±19. Out of 547 respondents, female were 397(72.6%) and male were 150 (27.4%), 385(70.4%) respondents had less than 30 nmole/L of vitamin D3D2 level, mean ± SD was 25.5±18. No significant association was found between gender of the respondents and vitaminD3D2 status of the study population (p value was 0.619). A significant difference was found between vitamin D3D2 (nmole/L) level and age of the respondents (p value was 0.002). Comparison of vitamin D3D2 status among Bangladesh, China, Malaysia and India was stated that vitamin D3D2 deficiency was more common in male than female. Conclusion: Vitamin D is an important vitamin which impacts many systems in the body but this study indicates that more than 70% of the Bangladeshi population are vitamin D deficient. In order to maintain healthy bone and boost up immunity as well as to sustain a balanced weight one has to ensure proper level of this indispensable protector of human being in one's bloodstream.
... Although vitamin D can be supplied by cutaneous synthesis on sunlight exposure (90 % of supply) and dietary intake (10 %), its insufficiency or deficiency remains a global health issue affecting more than one billion people, particularly the elderly population [5,6]. Several factors are associated with vitamin D status, including geographic latitude, altitude, seasons, dietary vitamin D intake, ethnicity, lifestyle and chronic diseases [6][7][8]. Interestingly, vitamin D status seems to differ upon sex too, with some studies demonstrating that higher vitamin D status in females [9], and others in males [10]. ...
... In this study, vitamin D status was found to be negatively associated with FMI and VFA in two sexes. Although there are many other methods for measuring FMI and VFA, such as computed tomography (CT), magnetic resonance imaging (MRI), and dual-energy X-ray absorptiometry (DXA), BIA has several advantages including ease of accessibility, no radiation exposure and relatively low cost [8,32]. Evidence also suggested that Inbody 770 was a reliable tool to measure body fat among ambulatory participants with a delta of − 0.9 ± 2.6 (5 % limits of agreement 6.0 to + 4.2) and a concordance correlation coefficient of 0.97 (95 % CI, 0.96-0.98) ...
Article
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Backgrounds: Vitamin D deficiency and insufficiency in older adults seems to be common, but the prevalence estimates are lacking in West China. Previous studies suggested that low vitamin D status was associated with obesity. However, most of them evaluated obesity based on body mass index (BMI) and there are no studies at present exploring the association between vitamin D status and different obesity markers. The present study aims to investigate the prevalence of low vitamin D status and evaluate the association between the vitamin D status and different obesity markers among older adults in West China. Methods: Data was based on the baseline of West China Health and Aging Trends study (WCHAT). All of the participants were older than 60 years old in the present study. Vitamin D status was based on laboratory data, and obesity markers were assessed by bioelectrical impedance analysis (BIA) using the InBody 770 analyzer. Multiple linear regression was performed to find the association between the vitamin D status and various obesity markers. Results: The study included 2661 individuals (mean age: 67.7 ± 6.0 years; males: 41 %). The mean vitamin D level was 18.8 ± 6.3 ng/ml (range: 5 to 59 ng/ml); 5.2 % of participants had a sufficient level of vitamin D, 31.8 % had vitamin D insufficiency, and 63.0 % had vitamin D deficiency. Our results showed that vitamin D status was negatively associated with fat mass index (FMI), visceral fat area (VFA), and waist-hip ratio (WHR) in both sexes. Comparing to other obesity markers, WHR had the strongest correlation with vitamin D status in both sexes (β = -6.090, P = 0.046 in males; β = -11.253, P < 0.001 in females). No significant association was found between vitamin D status and BMI in males. Conclusion: The prevalence of vitamin D insufficiency and deficiency among older adults in West China was high. Among the older adults in west China, WHR showed stronger association with vitamin D status and was better for the prediction of vitamin D insufficiency or deficiency in both sexes, compared to BMI. Trial registration: Chinese Clinical Trial Registry: ChiCTR1800018895 .
... Vitamin D deficiency is estimated to affect 70% of the United States population from the Health and Nutrition Examination Survey from 2000 to 2004 [12]. Within the medical community, much attention has been placed on the importance of vitamin D supplementation. ...
... When enrolling subjects at our single center, we found that 68% of all subjects who applied were found to be deficient in vitamin D. This aligned with the reported literature [12]. Our randomized, prospective study demonstrated that group 2 (100,000U Vitamin D2 weekly) clearly provided not only an expeditious correction for subjects with low vitamin D levels but also a sustained serum level over 12-weeks. ...
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Introduction Vitamin D has gained attention in the medical community due to its critical role in calcium homeostasis and overall bone health. No standard vitamin D dosing protocol in fracture care has been established for patients deficient in 25-hydroxyvitamin D. This prospective and randomized study aimed to find a dosing regimen that would safely achieve and maintain a therapeutic level of 25-hydroxyvitamin D in deficient patients over three months. Materials and methods Between June 2016 and May 2017, 48 patients with baseline total 25-hydroxyvitamin D less than 30.0 ng/mL were randomly assigned to either group one (one dose of 100,000 international units (IU) of Vitamin D2) or group 2 (100,000 IU of Vitamin D2 once weekly for twelve weeks) or group 3 (50,000 IU of Vitamin D2 daily for ten days followed by 2,000 IU of Vitamin D3 daily for 74 days). Baseline serum levels were drawn followed by interval levels at week 2, 6 and 12. The primary outcome was to determine which protocol could achieve and maintain therapeutic levels of total 25-hydroxyvitamin D over the course of three months. Our secondary outcome was to monitor for negative side effects. Results Group 1 did not show any statistically significant increase in serum levels and had no reported side effects. There was a statistically significant increase in serum total 25-hydroxyvitamin D in group 2 between all-time points except between weeks 6 and 12. Two (12.5%) participants in group 2 reported side effects. Group 3 had the greatest change in serum levels from weeks 0 to 2 but had a significant decrease between weeks 2 and 6. No change was seen between weeks 6 and 12. Three (17.5%) participants in group 3 reported side effects. Conclusions Group 2 sustained and maintained a satisfactory level of total 25-hydroxyvitamin D over three months without any severe side effects.
... See Table 1 for the abbreviations and descriptions of the United States/Russia (UR) cases from this study. combination of genetic (pigmentation) and socioeconomic factors (Forrest & Stuhldreher, 2011). On the other hand, there are several serious harmful effects of increased UV-B including sunburn, photoaging, skin cancer, and cataracts (MacKie, 2000). ...
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For the first time, we use a modern climate model with interactive chemistry including the effects of aerosols on photolysis rates to simulate the consequences of regional and global scale nuclear wars (injecting 5 and 150 Tg of soot respectively) for the ozone layer and surface ultraviolet (UV) light. For a global nuclear war, heating in the stratosphere, reduced photolysis, and an increase in catalytic loss from the HOx cycle cause a 15 year‐long reduction in the ozone column, with a peak loss of 75% globally and 65% in the tropics. This is larger than predictions from the 1980s, which assumed large injections of nitrogen oxides (NOx), but did not include the effects of smoke. NOx from the fireball and the fires provide a small (5%) increase to the global average ozone loss for the first few years. Initially, soot would shield the surface from UV‐B, but UV Index values would become extreme: greater than 35 in the tropics for 4 years, and greater than 45 during the summer in the southern polar regions for 3 years. For a regional war, global column ozone would be reduced by 25% with recovery taking 12 years. This is similar to previous simulations, but with a faster recovery time due to a shorter lifetime for soot in our simulations. In‐line photolysis provides process specific action spectra enabling future integration with biogeochemistry models and allows output that quantifies the potential health impacts from changes in surface UV for this and other larger aerosol injections.
... The overriding aim of the presented study is to draw attention to the fact that in the analyzed group of patients with angiographically confirmed coronary artery disease, only 6% of the participants presented with optimal concentrations of vitamin D, and as many as 22% of patients had severe deficiency. As mentioned in the introduction, vitamin D deficiency is associated with important risk factors related to leading causes of death [16]. Considering the fact that currently available sources of vitamin D (e.g. ...
Article
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Dane epidemiologiczne dotyczące stężenia witaminy D w surowicy w populacji polskich chorych z angiograficznie potwierdzoną chorobą wieńcową są ograniczone. Celem pracy była prospektywna ocena stężenia witaminy D w grupie kolejnych chorych Oddziału Kardiologii Szpitala Bielańskiego w War-szawie skierowanych do zabiegu koronarografii z powodu podejrzenia choroby wieńcowej. Materiał i metody. W badaniu wzięło udział łącznie 1043 chorych (374 kobiet i 669 mężczyzn w wieku 66,9±11,0 lat) zakwalifikowanych do badania w okresie czasu pomiędzy 2013 a 2017 rokiem. Stężenia 25(OH)D w osoczu oceniano metodą elektrochemiluminescencji. Wyniki. Mediana wartości stężenia 25(OH)D w badanej grupie wyno-siła 15,2 ng/ml (zakres: 4,0-55,0 ng/ml). Optymalne stężenie 25(OH)D (tj. równe lub większe niż 30 ng/ml) stwierdzono u 64 pacjentów (6%). Ciężki niedobór (poniżej 10 ng/ml) stwierdzono u 229 chorych (22%). Umiarkowany niedobór (stężenie równe lub większe niż 10 ng/ml i mniejsze niż 20 ng/ml) i łagodny niedobór (stężenie równe lub więk-sze niż 20 ng/ml i mniejsze niż 30 ng/ml) zaobserwowano u odpo-wiednio 525 (50%) i 225 chorych (22%). Wnioski. U 94% mieszkańców centralnej Polski z angiograficznie po-twierdzoną chorobą wieńcową stwierdzono niedobór witaminy D. 22% chorych znalazło się w grupie ciężkiego niedoboru witaminy D. Mając na względzie udokumentowany wpływ witaminy D na układ sercowo-naczy-niowy oraz to, że choroby układu krążenia (w tym choroba wieńcowa) są nadal najczęstszą przyczyną zgonów w krajach rozwiniętych, należy roz-ważyć strategie profilaktyczne i lecznicze w zakresie zwalczania niedo-boru 25(OH)D w tej grupie polskich chorych. Słowa kluczowe: witamina D, choroba wieńcowa Pol Merkur Lekarski, 2021; XLIX (292); 278-282 Vitamin D deficiency among Polish patients with angiographically confirmed coronary heart disease Epidemiological data on serum vitamin D levels in the population of Polish patients with angiographically confirmed coronary artery disease are limited. The aim of the study was to prospectively assess the concentrations of vitamin D in a group of patients from the Cardiological Department in Bielanski Hospital in Warsaw referred for coronary angiography due to suspected coronary artery disease. Materials and methods. The study included a total of 1,043 qualified patients (374 women and 669 men, age: 66,9±11,0 years) who underwent coronary angiography between the years of 2013 and 2017. Plasma 25(OH)D concentrations were assessed by electrochemiluminescence. Results. The median 25(OH)D concentration in the study group was 15.2 ng/ml (range: 4.0-55.0 ng/ml). Optimal 25(OH)D concentrations (ie., equal to or greater than 30 ng/ml) were found in 64 patients (6%). Severe deficiencies (less than 10 ng/ml) were found in 229 patients (22%). Moderate deficiencies (concentration equal to or greater than 10 ng/ml and less than 20 ng/ml) and mild deficiencies (concentration equal to or greater than 20 ng/ml and less than 30 ng/ml) were observed in 525 (50%) and 225 patients (22%), respectively. Conclusions. Vitamin D deficiency was found in 94% of residents of central Poland with angiographically confirmed coronary artery disease. 22% of patients had a severe vitamin D deficiency. Due to the documented effects of vitamin D on the cardiovascular system and the fact that cardiovascular disease (including coronary artery disease) is still the most common cause of death in developed countries, prophylactic and therapeutic strategies should be considered to combat 25(OH)D deficiency in this group of Polish patients.
... This may in part explain the discrepancies in the results between serum and dietary vitamin D in relation to NAFLD, that is, NAFLD was associated with lower serum vitamin D concentrations as suggested by previous studies but not related to dietary vitamin D intake observed in our study. That said, consuming an adequate amount of vitamin D from diet and/or supplement is nevertheless relevant for high-risk populations, for example blacks and Hispanics among whom high prevalence of vitamin D deficiency has been reported [55]. In fact, we observed Hispanics had the lowest vitamin D intake (from diet and supplement) (12.6 ± 0.7 µg/day) among the racial/ethnic groups in the current study; the value was more than two-fold lower compared to whites (27.2 ± 3.3 µg/day). ...
Article
Lipid-soluble micronutrients may be beneficial to non-alcoholic fatty liver disease due to their important roles in metabolism and maintaining tissue functions. Utilizing 2017-2018 National Health and Nutrition Examination Survey, this study examined the potential overall and race/ethnicity-specific (black, Hispanic and white) associations of dietary lipid-soluble micronutrients (α-tocopherol, retinol, vitamin D, β-carotene and total carotenoids) with hepatic steatosis. The analysis included 4376 adults (1037 blacks, 981 Hispanics, 1549 whites) aged ≥20 years who completed the transient elastography examination with dietary data available. Odds ratios (OR) and 95% confidence intervals (95%CI) were estimated using logistic regressions. The age-adjusted prevalence of steatosis was 20.9% for blacks, 34.0% for Hispanics and 28.7% for whites. Overall, dietary α-tocopherol was inversely associated with steatosis (highest vs. lowest quartile: OR = 0.51, 95%CI = 0.35-0.74, Ptrend = 0.0003). The associations remained significant among blacks (highest vs. lowest tertile: OR = 0.45, 95%CI = 0.26-0.77, Ptrend = 0.002) and whites (highest vs. lowest tertile: OR = 0.56, 95%CI = 0.33-0.94, Ptrend = 0.02). Higher α-tocopherol intake was associated with lower odds of steatosis among all (Ptrend = 0.016) and black participants (Ptrend = 0.003) classified as never/rare/occasional alcohol drinkers. There was a trend suggesting higher β-carotene intake with lower odds of steatosis (Ptrend = 0.01). Our results suggest potential protective effects of dietary vitamin E as α-tocopherol on steatosis particularly among blacks.
... Vitamin D deficiency (VDD) is a known risk factor for osteopenia of prematurity 2 . In northern India VDD prevalence in pregnant women is 93.5%, whereas in southern India VDD prevalence is 61% 3,4 . ...
... Vitamin D deficiency is diagnosed through a blood test for the level of 25-hydroxyvitamin D in the blood. Most studies have defined 25-hydroxyvitamin D levels of <20 ng/mL as vitamin D deficiency [4]. Based on this cutoff level, the prevalence of vitamin D deficiency was approximately ≥70% in South Asia, and it varied from 6% to 70% in Southeast Asia [5]. ...
Article
Objective: This study was conducted to estimate the common signs and symptoms present in patients with vitamin D deficiency at a children's specialty hospital in Dubai, United Arab Emirates (UAE). Methods: This descriptive cross-sectional study (n = 805) examined patients aged <18 years with a serum 25-hydroxy vitamin D concentration of <50 ng/mL and presenting to the hospital between 2017 and 2018. Variables (age, gender, nationality, vitamin D levels, signs and symptoms, and primary complaint) were described using frequencies and mean values (SD). Chi-square and Kruskal-Wallis tests were conducted. Results: Among the 805 patients, 315 (39.2%) had vitamin D deficiency (<20 ng/mL). Regarding the symptoms of these 315 patients, 26% (n = 82) of them were asymptomatic, 13.3% (n = 42) of them had endocrine symptoms and other/rare symptoms, and 11.7% (n = 37) of them had gastrointestinal symptoms. The least common symptoms were found in the mixed category (mixed symptoms of different body systems), consisting of 3.5% (n = 11) of patients. Vitamin D deficiency was more common among female patients (44.8%) and Emiratis (40.5%), and the average age for patients to have vitamin D deficiency was nine years. Conclusion: To our knowledge, this is one of the first studies in the United Arab Emirates to focus on and examine patients with low vitamin D levels in detail. Determining the most frequent symptoms is helpful for healthcare practitioners because our results showed that most patients with the deficiency were asymptomatic. Hence, we recommend performing regular checkups for healthy and asymptomatic children to detect vitamin D deficiency before they show any symptoms.
... Vitamin D deficiency is prevalent in both developed and developing countries and is determined by low serum 25-hydroxy vitamin D (< 25 nmol/l) levels [10]. In the US, overall vitamin D deficiency prevalence rate was 41.6% and highest in blacks followed by Hispanics [11]. ...
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Purpose Many smaller studies have previously shown a significant association between thyroid autoantibody induced hypothyroidism and lower serum vitamin D levels. However, these finding have not been confirmed by large-scale studies. In this study, we evaluated the relationship between hypothyroidism and vitamin D levels using a large population-based data. Methods For this study, we used National Health and Nutrition Examination Survey (NHANES) during the years 2007–2012. We categorized participants into three clinically relevant categories based on vitamin D levels: optimal, intermediate and deficient. Participants were also split into hypothyroid and hyperthyroid. Weighted multivariable logistic regression analyses were used to calculate the odds of being hypothyroid based on vitamin D status. Results A total of 7943 participants were included in this study, of which 614 (7.7%) were having hypothyroidism. Nearly 25.6% of hypothyroid patients had vitamin D deficiency, compared to 20.6% among normal controls. Adjusted logistic regression analyses showed that the odds of developing hypothyroidism were significantly higher among patients with intermediate (adjusted odds ratio [aOR], 1.7, 95% CI: 1.5–1.8) and deficient levels of vitamin D (aOR, 1.6, 95% CI: 1.4–1.9). Conclusion Low vitamin D levels are associated with autoimmune hypothyroidism. Healthcare initiatives such as mass vitamin D deficiency screening among at-risk population could significantly decrease the risk for hypothyroidism in the long-term.
... Another study found that vitamin D stimulates innate immunity and modulates acquired immunity [35], which may be a reason for the meta-analysis results. Vitamin D deficiency is common and is more in people with darker skin, obesity, old age, or less exposure to the sun [36,37]. Therefore, people who are at risk for vitamin D deficiency, especially during the COVID-19 epidemic, should take vitamin D supplements to maintain optimal blood circulation (75-125 nmol/L) [38]. ...
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The COVID-19 pandemic, which causes severe respiratory tract infections in humans, has become a global health concern and is spreading rapidly. At present, the most important issue associated with COVID-19 is the immune system and the factors that affect it. It is well known that cow’s milk is highly rich in micronutrients that increase and strengthen the immune system. Research shows that the administration of these nutrients is very effective in fighting COVID-19, and a deficiency in any of them can be a weakness in the fight against the virus. On the other hand, cow’s milk is accessible to the whole population, and drinking colostrum, raw, and micro-filtered milk from cows vaccinated against SARS-CoV-2 could provide individuals with short-term protection against the SARS-CoV-2 infection until vaccines become commercially available. This review aimed to discuss the effects of milk vitamins, minerals, and bioactive peptides on general health in humans to combat viral diseases, especially COVID-19, and to what extent cow’s milk consumption plays a role in providing these metabolites. Cow’s milk contains many bioactive compounds that include vitamins, minerals, biogenic amines, nucleotides, oligosaccharides, organic acids, and immunoglobulins. Humans can meet a significant portion of their requirements for vitamins and minerals through the consumption of cow’s milk. Recent studies have shown that micronutrients such as vitamins D, E, B, C, and A as well as minerals Zn, Cu, Mg, I, and Se and bioactive peptides, each can have positive and significant effects on strengthening the immune system and general health in humans.
... In the United States, the third National Health and Nutrition Examination Survey showed a prevalence of vitamin D deficiency in approximately 30% of Americans [9]. An even higher prevalence was observed in certain ethnic groups, with >80% of African American adults and >60% of Hispanic adults having serum concentrations of 25(OH)D ≤20 ng/mL [10]. Among East Asians, 32.1% to 75.2% of Chinese adults and 53.6% of Japanese adults have concentrations of 25(OH)D ≤20 ng/mL [11]. ...
Article
Background: Epidemiological data have shown that vitamin D deficiency is highly prevalent in Korea. Genetic factors influencing vitamin D deficiency in humans have been studied in Europe but are less known in East Asian countries, including Korea. We aimed to investigate the genetic factors related to vitamin D levels in Korean people using a genome-wide association study (GWAS). Methods: We included 12,642 subjects from three different genetic cohorts consisting of Korean participants. The GWAS was performed on 7,590 individuals using linear or logistic regression meta- and mega-analyses. After identifying significant single nucleotide polymorphisms (SNPs), we calculated heritability and performed replication and rare variant analyses. In addition, expression quantitative trait locus (eQTL) analysis for significant SNPs was performed. Results: rs12803256, in the actin epsilon 1, pseudogene (ACTE1P) gene, was identified as a novel polymorphism associated with vitamin D deficiency. SNPs, such as rs11723621 and rs7041, in the group-specific component gene (GC) and rs11023332 in the phosphodiesterase 3B (PDE3B) gene were significantly associated with vitamin D deficiency in both meta- and mega-analyses. The SNP heritability of the vitamin D concentration was estimated to be 7.23%. eQTL analysis for rs12803256 for the genes related to vitamin D metabolism, including glutamine-dependent NAD(+) synthetase (NADSYN1) and 7-dehydrocholesterol reductase (DHCR7), showed significantly different expression according to alleles. Conclusion: The genetic factors underlying vitamin D deficiency in Korea included polymorphisms in the GC, PDE3B, NADSYN1, and ACTE1P genes. The biological mechanism of a non-coding SNP (rs12803256) for DHCR7/NADSYN1 on vitamin D concentrations is unclear, warranting further investigations.
... Vitamin D is synthesized in the skin but can also be obtained from foods and supplements. Some studies had shown that milk consumers consistently had higher serum vitamin D levels [23,24]. The results of the US National Health and Nutrition Examination Survey (NHANES 2001-2010) demonstrated a signi cant association between milk consumption and serum vitamin D status in US population, and the probability of meeting vitamin D recommendations was greater in milk consumers vs. non-consumers [23]. ...
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Background: Vitamin D deficiency is a major public health problem in China while there are seldom reports about vitamin D nutrition status in Chinese college students. The purpose of this study is to explore the vitamin D status of the college freshmen who came from different provinces of China and to comprehensive analyze the effects of diet, physical activity, and UV protection on serum vitamin D levels. Methods: Totally 1,667 freshmen who came from 26 provinces, autonomous districts or municipalities, were recruited into this study. An online questionnaire was used to collect the information including demographic status, diet habit, physical activity, and UV protection of the participants. Serum 25(OH)D3 concentrations were measured using a liquid chromatograph mass spectrometer. Multivariate linear regression analyses were used to explore the comprehensive influence of diet, physical activity, and UV protection on serum 25(OH)D3 levels. Results: The average age of the subjects was18.55±0.90 years, with 23.0% male and 77.0% female. The mean serum 25(OH)D3 was 18.06±6.34ng/mL and the proportion of vitamin D deficiency and insufficiency was 67.5% and 27.8%, respectively. Multivariate linear regression indicated that milk and yogurt intake≥200mL/d, calcium or vitamin D supplements and average time of outdoor activity ≥60 min/day were positively linked to higher serum vitamin D while sweets intake ≥10g/d and higher UV protection index were negatively influenced serum vitamin D after adjusted for age, gender, students’ original residence, latitudes and longitude. Conclusions: Vitamin D deficiency is an important health problem in Chinese college students. Milk and yogurt intake and outdoor activity should be encouraged while sweets intake should be limited for preventing vitamin D deficiency. Public health policies should consider well-balanced guidelines on UV protection and vitamin D food fortification or supplementation.
... It is estimated that about one billion people suffers from vitamin D deficiency worldwide [3]. The prevalence of vitamin D deficiency is about 41.6% in the United States [4]. It is also highly prevalent in the Middle East [5]. ...
Article
Aims: The purpose of this study was to assess the knowledge and attitude towards vitamin D and sunlight exposure among female university students. Study Design: Cross Sectional study design. Place and Duration of Study: The study was conducted among 500 female Saudi students in Princess Nourah Bint Abdulrahman University (PNU). Methodology: A self-administered questionnaire was used to assess the knowledge about vitamin D sources, health benefits and effects of vitamin D deficiency and assessing the attitude towards vitamin D and sunlight exposure. Results: The present study recognized that health college students (52.7%) had better knowledge than non-health college students (47.3%). Although PNU students had good knowledge about vitamin D, only 6.0% of them knew the current recommended daily dose. Female students showed good behavior and attitude in terms of high frequency of sunlight exposure daily (34.8%). Educational institutions were the main sources of information about vitamin D (43%). Hot weather (54.8%) and fear of pigmentation (51.2) were the main reasons for limited sunlight exposure among students. Conclusion: There was a good level of knowledge (52.2%) about vitamin D sources, benefits and effects of vitamin D deficiency among female students. In fact, health college students had better knowledge about vitamin D than non-health college students. Hot weather (54.8%) and fear of pigmentation (51.2%) were the main barriers to sunlight exposure.
... Although our sample size was small, it was powered to identify seasonal variations in 25(OH)D levels and a positive effect of oral vitamin D supplementation on serum level. Such a high prevalence of vitamin D deficiency has been found in general medical inpatients (26) and populations with poor health (27) and corresponds to the poor and complex health issues that patients with AL amyloidosis often encounter. ...
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IntroductionVitamin D deficiency is common, but no data have been reported on vitamin D levels in light chain (AL) amyloidosis.Patients and Methods In this exploratory study, stored serum samples from 173 patients with newly diagnosed AL amyloidosis were analyzed for vitamin studies which included 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)2D] and vitamin D binding protein (DBP). Measurements were made by liquid chromatography-tandem mass spectrometry. Kidney survival and overall survival (OS) were assessed in association to vitamin D status.ResultsCardiac and kidney involvement occurred in 69% and 63% of patients, respectively. 25(OH)D deficiency (<20 ng/mL) was seen in 56.6% of the patients and was notably found among patients with heavy proteinuria (96%), hypoalbuminemia (84.3%) and morbidly obese patients (68.3%). Heavy proteinuria (>5 gr/24-h) and vitamin D supplementation were independent predictors of 25(OH)D level on nominal multivariate regression analysis. 1,25(0H)2D deficiency was noted in 37.6% of patients and was independently associated with low eGFR and hypoalbuminemia. Progression to ESRD occurred in 23.7% of evaluable patients. Patients who progressed to ESRD had lower serum 25(OH)D and 1,25(OH)2D levels compared to those who did not progress to ESRD. On a multivariate analysis, severe 25(OH)D deficiency was an independent predictor of progression to ESRD as was renal stage, while 1,25(OH)2D deficiency was not.Conclusions Hypovitaminosis D is common in AL amyloidosis, particularly among patients with heavy proteinuria. Severe 25(OH)D deficiency at time of diagnosis predicts progression to ESRD.
... Vitamin D deficiency is related to multiple health issues, including cardiovascular disease, cancer, metabolic syndrome and infection [1]. In the general population, the prevalence of vitamin D deficiency exists ranges from 20 to 80% (3)(4)(5), and in critical ill patients, the prevalence and severity of vitamin D deficiency increase. In addition to baseline vitamin D deficiency, decreased intake and absorption, increased losses and decreased production of vitamin D (6), enhanced conversion of 25-hydroxyvitamin D (25(OH)D) to the active 1,25-dihydroxyvitamin D3 (1,25(OH)2D) (7), and acute fluid shifts (8) may result in severely low vitamin D levels. ...
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Background: Vitamin D deficiency is common in the general population worldwide, and the prevalence and severity of vitamin D deficiency increase in critically ill patients. The prevalence of vitamin D deficiency in a community-based cohort in Northern Taiwan was 22.4%. This multicenter cohort study investigated the prevalence of vitamin D deficiency and associated factors in critically ill patients in Northern Taiwan. Methods: Critically ill patients were enrolled and divided into five groups according to their length of stay at intensive care units (ICUs) during enrolment as follows: group 1, <2 days with expected short ICU stay; group 2, <2 days with expected long ICU stay; group 3, 3-7 days; group 4, 8-14 days; and group 5, 15-28 days. Vitamin D deficiency was defined as a serum 25-hydroxyvitamin D (25(OH)D) level < 20 ng/ml, and severe vitamin D deficiency was defined as a 25(OH)D level < 12 ng/ml. The primary analysis was the prevalence of vitamin D deficiency. The exploratory analyses were serial follow-up vitamin D levels in group 2, associated factors for vitamin D deficiency, and the effect of vitamin D deficiency on clinical outcomes in critically ill patients. Results: The prevalence of vitamin D deficiency was 59% [95% confidence interval (CI) 55-62%], and the prevalence of severe vitamin D deficiency was 18% (95% CI 15-21%). The median vitamin D level for all enrolled critically ill patients was 18.3 (13.7-23.9) ng/ml. In group 2, the median vitamin D levels were <20 ng/ml during the serial follow-up. According to the multivariable analysis, young age, female gender, low albumin level, high parathyroid hormone (PTH) level, and high sequential organ failure assessment (SOFA) score were significantly associated risk factors for vitamin D deficiency. Patients with vitamin D deficiency had longer ventilator use duration and length of ICU stay. However, the 28- and 90-day mortality rate were not associated with vitamin D deficiency. Conclusions: This study demonstrated that the prevalence of vitamin D deficiency is high in critically ill patients. Age, gender, albumin level, PTH level, and SOFA score were significantly associated with vitamin D deficiency in these patients.
... The overriding aim of the presented study is to draw attention to the fact that in the analyzed group of patients with angiographically confirmed coronary artery disease, only 6% of the participants presented with optimal concentrations of vitamin D, and as many as 22% of patients had severe deficiency. As mentioned in the introduction, vitamin D deficiency is associated with important risk factors related to leading causes of death [16]. Considering the fact that currently available sources of vitamin D (e.g. ...
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Epidemiological data on serum vitamin D levels in the population of Polish patients with angiographically confirmed coronary artery disease are limited. Aim: The aim of the study was to prospectively assess the concentrations of vitamin D in a group of patients from the Cardiological Department in Bielanski Hospital in Warsaw referred for coronary angiography due to suspected coronary artery disease. Materials and methods: The study included a total of 1,043 qualified patients (374 women and 669 men, age: 66,9±11,0 years) who underwent coronary angiography between the years of 2013 and 2017. Plasma 25(OH)D concentrations were assessed by electrochemiluminescence. Results: The median 25(OH)D concentration in the study group was 15.2 ng/ml (range: 4.0 - 55.0 ng/ml). Optimal 25(OH)D concentrations (ie., equal to or greater than 30 ng/ml) were found in 64 patients (6%). Severe deficiencies (less than 10 ng/ml) were found in 229 patients (22%). Moderate deficiencies (concentration equal to or greater than 10 ng/ml and less than 20 ng/ml) and mild deficiencies (concentration equal to or greater than 20 ng/ml and less than 30 ng/ml) were observed in 525 (50%) and 225 patients (22%), respectively. Conclusions: Vitamin D deficiency was found in 94% of residents of central Poland with angiographically confirmed coronary artery disease. 22% of patients had a severe vitamin D deficiency. Due to the documented effects of vitamin D on the cardiovascular system and the fact that cardiovascular disease (including coronary artery disease) is still the most common cause of death in developed countries, prophylactic and therapeutic strategies should be considered to combat 25(OH)D deficiency in this group of Polish patients.
... [3][4][5][6][7] In the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2006, 42% of participants ≥20 years of age had vitamin D levels of <20 ng/mL. 8 Many studies have shown that VDD is significantly higher among urban populations, obese individuals, and in the U.S. Midwest. 9,10 However, there is not strong evidence for causation. ...
Article
Vitamin D deficiency (VDD) is significantly higher among urban populations in the U.S. Midwest, with African Americans being disproportionately affected. There is ongoing debate surrounding who and how often individuals should be screened for VDD. This study aimed to understand the prevalence of VDD, associated risk factors, and discrepancies in testing at an urban-based internal medicine residency clinic. Data were retrospectively collected on all adult patients seen by the clinic during 2018 and descriptive statistical analysis performed. Among 3976 total patients (mean age: 53 years), 18% (n = 698) had vitamin D levels analyzed, with deficiency found in 71% of those tested. Mean age of the tested cohort was 59 years, and women (68%) and African Americans (72%) were found more likely to be tested. Women and patients with certain medical conditions were more likely to be tested (P < 0.02 for all) but were not more likely to have VDD. Individuals with a diagnosis of chronic kidney disease were less likely to have VDD (P = 0.002). Vitamin D levels typically showed improvement after retesting. A low testing rate could contribute to missed diagnoses. Overall, this study revealed that differences in rate of testing do not necessarily correlate to patients’ demographical risk of VDD. Clinicians may benefit from a standardized vitamin D testing protocol.
... Nevertheless, the relationship between latitude and COVID-19 epidemic (in Figure 1) has likely a vitamin D causal component [19]. For example, 41.6% of US adults have vitamin D deficiency, with serum 25-hydroxyvitamin D less than 50 nmol/L [20], while traditionally living East Africans have mean serum 25-hydroxyvitamin D of 115 nmol/L [21]. ...
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Randomized controlled trials (RCTs) are considered the "gold standard" in clinical medicine. Perhaps for this reason, health authorities all over the world have assumed the universal validity of RCTs and have not recognized that RCT results may not be valid everywhere or for the epidemiology of infectious diseases. Using the Pfizer-BioNTech vaccine trial as a case study, we illustrate the limitations of the RCT and show that the results may be inappropriate for COVID-19 epidemiology. This critique explains why health authorities have not recognized that the vaccines have failed to stem the growth of the COVID-19 pandemic. This insight has also broader implications for the global pharmaceutical industry.
... Grant et al. suggested that there could be a significant reduction in many healthcare costs related to diseases that have been associated with vitamin D deficiency [67,68]. Vitamin D insufficiency is linked to important risk factors of leading causes of death [69]. Clinicians and/or healthcare providers should be aware of the connection and offer adequate interventions to increase 25(OH)D concentration, especially in minority groups [70,71]. ...
Article
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Introduction. Vitamin D deficiency is a worldwide problem with a variety of health consequences. Vitamin D may reduce the risk of heart failure, however, evidence of the impact of vitamin D treatment on maintenance of cardiovascular health (i.e., preventing cardiovascular diseases) is conflicting due to lack of support from clinical trials. The reason for the failure of clinical trials to confirm an effect of vitamin D supplementation could be at least threefold: 1) too little vitamin D given to the participants or 2) lack of inclusion of only severely vitamin D-deficient populations or 3) study duration. The aim of this study was to characterize a group of cardiac patients who presented the lowest concentrations of 25-hydroxyvitamin D [25(OH)D]. Material and methods. Results of 92 diabetic cardiac patients aged between 41 and 89 years who experienced myocardial infarction, with significant coronary arteries changes, hospitalized due to acute coronary syndrome living in Warsaw were analyzed. Results. Patients presented median 25(OH)D concentration value of 11 ng/mL (range: 4-28 ng/mL). The only significant determinant of 25(OH)D concentration was the date of examination, with higher concentrations in summer than in winter. Conclusions. Vitamin D treatment in Polish cardiac patients aimed at reaching the optimal level of 30 ng/mL (75 nmol/L) seems to be necessary and implemented as soon as possible.
... However, there was no obese patient among our patients. In a study, it was reported that the prevalence of vitamin D deficiency (vitamin D concentration <20 ng/ml) was higher (53.8%) in obese patients compared to normal weight (33%) (Forrest & Stuhldreher, 2011). ...
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Objectives: Our aim in this study is to reveal the role of vitamin D deficiency in the pathogenesis of recurrent/chronic tonsillitis and to determine the expression of vascular epithelial growth factor (VEGF). Material and methods: This study was conducted between September and February. Thirty-two patients between the ages of 3 and 35 (mean age 9.71) with recurrent episodes of chronic tonsillitis were selected. Patients were divided into four groups according to their 25OHD levels. Patients with 25OHD levels 0-10 ng/ml were determined as Group 1, 11-20 ng/ml Group 2, 21-30 ng/ml Group 3, and 31-50 ng/ml control Group 4. Routine histological tissue sampling was performed for histopathological evaluation of the tonsillar tissues under light microscope (LM). Five micron sections were taken from the paraffin blocks and stained with Hematoxylin Eosin (HE) and Trichrome Masson (TCM). VEGF expression was examined immunohistochemically for each group. Results: Our analysis showed VEGF expression in all study groups (32 tonsillar tissues). Group 1 and Group 2 histopathological scores were significantly higher than the other groups (p < .001). There were significant differences in VEGF expressions between the four groups (p < .001). 25OHD levels of the patients in Groups 1 and 2 with strong VEGF expression were significantly lower than the other groups (p < .001). Conclusions: In conclusion, this study showed an increased angiogenesis in tonsil and an increase in VEGF expression of the tonsillar surface epithelium when blood serum 25OHD levels <20 ng/ml.
... Çalışmaya katılan bireylerin %71,2'sinin açık, %22'sinin buğday ve %6,8'inin koyu tenli olduğu, koyu ve buğday tenlilerin vitamin D düzeylerinin önemli bir şekilde düşük olduğu tespit edildi. Amerika'da yapılan bir çalışmada vitamin D eksikliği prevelansının beyaz ırkta (%30,9) düşük, siyah ırkta (%82,1) yüksek ve koyu ten rengine sahip İspanyol kökenli Güney Amerika'lılarda da (%62,90) yüksek olduğu bulunmuştur (18). Pigmentasyon arttıkça yani deri rengi koyulaştıkça deride previtamin D'nin provitamin D'ye dönüşümünü zorlaştırdığı ve koyu renkli ya da siyahi kişilerde yeterli vitamin D absorbsiyonu olabilmesi için daha fazla güneş ışığına maruz kalınması gerektiği belirtilmiştir (9,19). ...
Article
Objective:This study was conducted to find the lifestyles of individuals with vitamin D deficiency.Materials and Methods:This descriptive study was conducted on 250 individuals with vitamin D deficiency who referred to Erzurum Region Training and Research Hospital Endocrine and Metabolic Diseases Outpatient Clinic between April 2015 and October 2015. Questionnaires were used to collect the data.Results:Average vitamin D levels of the individuals were found as 11.82±5.73. It was found that 80.8% of the individuals did not use the vitamin D supplement, while vitamin D levels of those who did not use the supplement and those who used vitamin D drops were found to have significantly low vitamin D levels (p=0.000). Vitamin D levels of the individuals who had a diagnosis period of less than 6 months, those who did not use sun cream, those who were dark and wheat-skinned, those who did not eat fish and those who did not eat cheese were found to be significantly low (p0.05).Conclusion:Individuals who did not take vitamin D supplement, those who used vitamin D drops, those who had a diagnosis period of less than 6 months, those who did not use sun cream, those who did not eat fish and cheese and those who were dark and wheat-skinned had significantly low vitamin D levels.
... On the other hand, vitamin D deficiency, which afflicts about 73% of the world and 42% of the USA population (18,19), is often accompanied by NAFLD and plays an important role in its pathogenesis and progression. Many studies have indicated a strong association between vitamin D deficiency and NAFLD. ...
Article
Background: Due to the interruption of the EHC pathway in NAFLD patients, we hypothesized that parenteral vitamin D supplementation is superior to oral in vitamin D insufficient patients with NAFLD. Therefore, this study aimed to compare the efficacy of oral and parenteral routes of vitamin D supplementation on serum 25(OH) vitamin D levels in patients with NAFLD. Methods: In this prospective randomized trial, 66 NAFLD cases with vitamin D deficiency were studied. For 33 cases, oral vitamin D was supplemented, whereas the other 33 patients were given an intramuscular injection of vitamin D. Laboratory tests and liver ultrasound were performed at the beginning and the end of the trial for each subject. Results: Regardless of the drug administration route, at the end of this trial the mean of serum 25-hydroxy vitamin D level increased from 8.74±2.47 to 33.16±17.61 (P=0.00), and the mean±SD for serum triglyceride decreased from 191.46±92.79 to 166.00±68.30 (P=0.02), both were statistically significant. Liver ultrasound reported statistically significant changes in the grade of fatty liver disease (P=0.003). In the comparison between the two groups, serum 25-hydroxy vitamin D level changes were not statistically significant (P=0.788). Conclusion: The intramuscular method of supplementation was not better than the oral route in improving serum 25(OH) vitamin D levels in NAFLD patients. In this study, the impaired EHC and vitamin D absorption inhibitor factors in NAFLD patients did not affect the final result of serum vitamin D levels significantly.
... In the race-ethnicity subgroup analysis, we found a significant nonlinear relation between breast cancer and serum 25(OH)D only in NHW but not in other race-ethnicities. Lack of relation between breast cancer and serum 25(OH)D in NHB and in MA/H was more likely due to lower sample sizes and lower serum 25(OH) concentrations in these race-ethnicities compared to the NHW race [44]. Further studies are warranted in ethnic minorities with a large sample size to confirm these observed associations. ...
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The association between serum 25-hydroxyvitamin D [25(OH)D] concentration and breast cancer risk in postmenopausal women is not well understood. The aim of this study was to investigate the association between serum 25(OH)D concentration and breast cancer in postmenopausal women in the United States using nationally representative sample surveys. We used the data from seven cycles of National Health and Nutrition Examination Surveys from 2001 to 2014. Participants were non-institutionalized postmenopausal women (n = 8108). In restricted cubic spline analysis, a significant, nonlinear, invert ‘U’ relationship was observed between serum 25(OH)D concentrations and breast cancer in postmenopausal women (p = 0.029). Overall, breast cancer risk was highest (OR = 1.5) between 70 nmol/L and 80 nmol/L of serum 25(OH)D concentration. Then after serum 25(OH)D 80 nmol/L concentration, the breast cancer risk declined. In multivariate-adjusted logistic regression, the risk of having breast cancer was significantly higher in serum 25(OH)D 75–˂100 nmol/L category compared to the 25(OH)D < 30 nmol/L category [OR and 95% CI: 2.4 (1.4–4.0)]. In conclusion, serum vitamin D concentrations ≥ 100 nmol/L are associated with reduced risk of breast cancer in postmenopausal women. Controlled trials are required to verify if serum 25(OH)D ≥ 100 nmol/L offers protection against breast cancer in postmenopausal women.
... 25(OH)D is a well-known steroid hormone, which is essential for the maintenance of calcium homeostasis and for bone health [27]. However, due to the lack of outdoor activities and unhealthy eating habits, vitamin D deficiency has now become a global health burden regardless of regions, races, age and sex [4,28]. As risk factors are highly overlapped, many studies have revealed that lower 25(OH)D status were more commonly identified in individuals with MetS. ...
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Background The comparatively low 25 hydroxyvitamin D [25(OH)D] levels have been reported in patients with metabolic syndrome (MetS). Herein we investigated the cross-sectional and longitudinal relationships between serum 25(OH)D levels and MetS risk profile in northern middle-aged Chinese subjects without vitamin D supplementation. Methods A cohort of 211 participants including 151 MetS patients and 60 controls at 20–69 years of age were enrolled from suburban Beijing, China. The recruited MetS patients were subjected to diet and exercise counselling for 1-year. All subjects at baseline and MetS patients after intervention underwent clinical evaluations. Results Serum 25(OH)D levels were significantly decreased in MetS patients. 25(OH)D levels were inversely related to MetS score, fasting blood glucose (FBG) and triglyceride-glucose index (TyG) after adjusting for cofounders (all P < 0.05). Participants in the lowest tertile of 25(OH)D levels had increased odds for MetS (P = 0.045), elevated FBG (P = 0.004) in all subjects, and one MetS score gain in MetS patients (P = 0.005). Longitudinally, the metabolic statuses as well as 25(OH)D levels of MetS patients were significantly improved (all P < 0.05), and the increase of 25(OH)D levels were inversely related to MetS scores, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), FBG, and TyG, while positively related to high-density lipoprotein cholesterol (HDL-C) after adjusting for confounders. Conclusions 25(OH)D levels were significantly decreased in MetS patients, and it was negatively associated with metabolic dysfunctions at baseline and 1-year after. Metabolic aberrations of MetS patients were significantly ameliorated with 1-year follow-up counselling accompanying by notably elevated 25(OH)D levels.
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Objective: Post-COVID-19 syndrome appears to be a multi-organ illness with a broad spectrum of manifestations, occurring after even mild acute illness. Limited data currently available has suggested that vitamin D deficiency may play a role in COVID-19 cases. However, to our knowledge, no study has examined the frequency of vitamin D deficiency in post-COVID-19 cases and its effect on the symptom severity. The aim of this study is to both screen the frequency of vitamin D deficiency in post-COVID-19 syndrome patients and to study its relation to persistent symptoms. Patients and methods: A cross-sectional, single-center study was conducted involving all cases attending post-COVID-19 follow-up clinic from November 2020 to May 2021. Complete history, clinical examination, and laboratory analysis [kidney functions, serum calcium, C-reactive protein, serum ferritin, Serum 25-(OH) vitamin D] was done as well as HRCT chest. Results: The study included 219 post-COVID-19 cases, 84% had deficient vitamin D levels (< 20 ng/dL); 11.4% had insufficient level (20-30 ng/dL) and only 4.9 % reported normal level. There was no link between levels of vitamin D with either the acute or post-COVID-19 symptoms in the studied groups. Conclusions: Despite the prevalence of vitamin D deficiency among the study population, no association was observed between the levels of vitamin D and post-COVID-19 symptoms. It appears that post-COVID-19 syndrome pathophysiology involves a more complex interaction with the immune system. Dedicated clinical trials are advised to better study vitamin D levels and the related disease severity in COVID-19 patients.
Chapter
This chapter describes current evidence for the role of inflammation in contributing to osteosarcopenia. It starts with an overview of chronic low-grade-inflammatory phenotype (CLIP) or inflammaging. It briefly introduces osteoimmunology with a focus on supportive evidence for the role of CLIP-inflammaging in promoting osteoclastogenesis and suppressing osteoblastogenesis resulting in age-related bone loss and osteoporosis. It then describes studies demonstrating the adverse impact of CLIP-inflammaging on skeletal muscle, leading to sarcopenia. Emerging data on pro-inflammatory crosstalk between fatty tissue and muscle and bone, as well as the potential role of the tumor necrosis factor (TNF)-related weak inducer of apoptosis (TWEAK) molecular pathway in contributing to osteosarcopenia are also discussed. Finally, it considers established and promising interventional strategies for osteosarcopenia, such as exercise, vitamin D supplementation, antiinflammatory biologics and drugs, as well as novel strategies targeting inflammation resolution mechanisms, stem cell therapy, and geroscience approach.
Article
Background: Although physical inactivity, obesity, and low serum vitamin D [25-hydroxyvitamin D, 25(OH)D] are common among women, joint associations among these biomarkers are not well-described. Materials and Methods: A total of 7553 healthy women received a comprehensive examination (2006-2018), including self-reported physical activity (PA), body mass index (BMI), waist circumference (WC), waist:height ratio (W:HT), percent body fat (%Fat), and 25(OH)D. Participants were divided into four categories of PA based on current guidelines: <500 (not meeting guidelines), 500-1000 (meeting guidelines), 1001-2500 (>1-2.5 times guidelines), and >2500 (>2.5 times guidelines) metabolic equivalent-minutes/week (MET-Min/wk), and were also classified by clinical cut points for adiposity measures and 25(OH)D. We examined trends of 25(OH)D and adiposity exposures across PA categories and calculated odds ratios (ORs) of vitamin D deficiency across categories of each adiposity exposure. We examined joint associations among PA and adiposity with 25(OH)D. Results: A positive trend was observed for 25(OH)D across PA categories (p < 0.001). Compared with normal weight status, the odds for 25(OH)D deficiency were significantly higher for overweight women within adiposity exposures (p for all <0.001). When examining joint associations, 25(OH)D was higher across PA categories within each stratum of BMI, WC, W:HT, and %Fat (p trend <0.007 for all). When examining PA and BMI as continuous variables, OR for vitamin D deficiency were 0.95 (95% confidence interval [CI]: 0.93-0.96) per 250 MET-minutes/week increment in PA, and 1.20 (95% CI: 1.17-1.23) per 2 kg/m2 increment in BMI. Conclusions: 25(OH)D levels are positively associated with PA and negatively associated with different measures of adiposity. Higher levels of PA attenuate the association between adiposity and 25(OH)D.
Article
Background Vitamin D deficiency (VDD, serum 25-hydroxyvitamin D [25OHD] <20 ng/mL) is prevalent in young adults and has been associated with adverse health outcomes including stress fracture during periods of increased physical activity such as military training. Foods commonly consumed at breakfast provide an important source of vitamin D, yet breakfast skipping is common among young adults. However, whether breakfast skipping is associated with VDD in young adults is unclear. Objectives This study aimed to determine whether breakfast skipping is associated with odds of VDD among recruits entering initial military training (IMT), and with changes in serum 25OHD during IMT. Additionally, whether diet quality and vitamin D intake mediated these associations was determined. Design Secondary analysis of individual participant data collected during five IMT studies. Breakfast skipping (≥3 time/wk) was self-reported. Dietary intake was determined using food frequency questionnaires, and vitamin D status was assessed using circulating 25OHD concentrations pre- and post-IMT Participants /setting: Participants were healthy Army, Air Force, and Marine recruits (N=1,569, 55% male, mean ± SD age 21±4yr) entering military service between 2010-2015 at Fort Jackson, SC, Fort Sill, OK, Lakeland Air Force Base, TX, or the Marine Corps Recruit Depot Parris Island, SC. Main outcome measures Primary outcomes were VDD pre-IMT and change in 25OHD from pre- to post-IMT. Statistical analysis performed Associations were determined using multivariate-adjusted logistic and linear regression and mediation models. Results 46% of military recruits were classified as breakfast skippers pre-IMT, and 30% were VDD. Breakfast skipping was associated with a higher odds of pre-IMT VDD (OR 1.5, 95% CI 1.1-1.9), and lower vitamin D intake and diet quality were partial mediators of the association. Serum 25OHD concentrations improved (p=0.01) among habitual breakfast skippers versus non-skippers during IMT, however regression to the mean could not be ruled out. Neither change in diet quality nor vitamin D intake were associated with change in 25OHD concentrations during IMT. Conclusions Breakfast skipping is prevalent among incoming military recruits and is associated with VDD. This relationship may be mediated by lower diet quality and vitamin D intake.
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Vitamin D, the sunshine vitamin, has received much attention for its roles in bone health and nonskeletal roles such as cell growth, cell differentiation, immune function, and several chronic disorders. While evidence exists for some roles, many other attributes are continuing to be studied and debated. Deficiency is common worldwide, including in the USA. Sunlight is a primary source for the vitamin, but adequate exposure to sunlight on a sustained basis is not practical. Dietary food sources are limited in vitamin D, barring fatty fish and fortified foods. Hence, supplements may be the practical source for ensuring optimal intake and for treatment of deficiency. Clinical manifestations of deficiency range from being asymptomatic to musculoskeletal pain, gait disturbances, and fracture. Vitamin D is a critical requirement for musculoskeletal health, a noncontroversial fact. But deficiency has also been linked to several health disorders including cancer, cardiovascular disease, heart failure, infections, cognition, depression, and more. Serum 25 (OH) D is the best measure of vitamin D status and is the storage form of the vitamin, whereas, 1,25(OH)2D is the physiological or active form. Vitamin D is necessary for maximal calcium and phosphorus absorption via the gut and other organs. Deficiency is common in geriatric individuals due to several factors, including decreased sunlight exposure, inefficient skin synthesis, and low intake. Newer guidelines from several organizations have commented on what constitutes adequate vitamin D levels, as well as inadequacy, and largely agree on a level of 20 ng/ml or higher and recommend a daily intake of 800 IU/d for adults over the age of 70 years. Dosages and approaches for addressing vitamin D deficiency vary, based on a given organization, and are listed. The preferred means of correction of deficiency is through supplements, rather than diet or sunlight exposure. Data from studies on vitamin D deficiency and supplementation in relation to outcomes are succinctly provided in tables.
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Introduction: The important role of micronutrient deficiencies in aging-related disorders including dementia is becoming increasingly evident. However, information on their burden in India is scarce, especially, among aging and rural communities. Methods: Prevalence of vitamin D, B12 and folic acid deficiency was measured in an ongoing, aging cohort, from rural India–Srinivaspura Aging Neurosenescence and COGnition (SANSCOG) study cohort. Serum level estimation of vitamin D, B12 and folic acid, using chemiluminescence immunoassay, was performed on 1648 subjects (872 males, 776 females). Results: Mean vitamin D, B12 and folic acid levels were 23.4 ± 10.6 ng/ml, 277.4 ± 194.4 pg/ml and 6 ± 3.5 ng/ml), respectively. Prevalence of low vitamin D (<30 ng/ml), vitamin D deficiency (<20 ng/ml), B12 deficiency (<200 pg/ml) and folic acid deficiency (<3 ng/ml) were 75.7, 39.1, 42.3, and 11.1%, respectively. Significantly more women had vitamin D deficiency, whereas more men had folic acid deficiency. Women belonging to the oldest age group (≥75 years) had the maximum burden of low vitamin D (94.3%) and folic acid deficiency (21.8%). Discussion: Older, rural-dwelling Indians have high burden of vitamin D and B12 deficiencies, which is concerning given the potentially negative consequences on cognition, immunity and frailty in the aging population. Urgent public health strategies are needed to address this issue and prevent or mitigate adverse consequences.
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Background: Observational studies, mostly among White populations, suggest that low vitamin D levels increase colorectal cancer (CRC) risk. African Americans, who are disproportionately burdened by CRC, often have lower vitamin D levels compared to other populations. Methods: We assessed predicted vitamin D score in relation to CRC among 49,534 participants in the Black Women's Health Study, a cohort of African American women followed from 1995 to 2017 through biennial questionnaires. We derived predicted vitamin D scores at each questionnaire cycle for all participants using a previously validated prediction model based on actual 25-hydroxyvitamin D values from a subset of participants. We calculated cumulative average predicted vitamin D score at every cycle by averaging scores from cycles up to and including that cycle. Using Cox proportional hazards regression, we estimated hazard ratios (HR) and 95% confidence intervals (CI) for CRC incidence according to predicted score quartiles. Results: Over follow-up, 488 incident CRC occurred. Compared to women in the highest quartile of predicted vitamin D score, those in the lowest had an estimated 41% (HR=1.41, 95% CI 1.05-1.90) higher CRC risk. Comparable HRs were 1.44 (95% CI 1.02-2.01) for colon and 1.34 (95% CI 0.70-2.56) for rectal cancer. Conclusions: Low vitamin D status may lead to elevated CRC risk in African American women. Impact: Our findings, taken together with established evidence that vitamin D levels are generally lower in African Americans than other U.S. groups, suggest that low vitamin D status may contribute to the disproportionately high CRC incidence among African Americans.
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Vitamin D is obtained from sunlight and dietary intake. After conversion in the liver to 25-hydroxyvitamin D, it is further converted to the active form of 1,25-dihydroxyvitamin D in the kidney. 1,25-Dihydroxyvitamin D is a hormone that interacts with vitamin D receptor complexes to impact a broad range of cellular functions. Classic functions include augmentation of calcium and phosphorus absorption in the gastrointestinal tract, calcium reabsorption in the kidney, and stimulation of bone osteoclasts, each of which maintains calcium homeostasis to prevent osteomalacia and rickets. Peripheral conversion of 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D is increasingly recognized and could play a role in additional impacts on immunity, cell survival, and insulin resistance among other effects. Although supplementation to treat vitamin D deficiency is justified, a large and growing body of clinical trials in cardiovascular disease, cancer, and skeletal health currently do not support unselected supplementation. However, in kidney disease, distinct abnormalities in vitamin D pathways occur. As kidney disease advances, deficient conversion of 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D leads to the development of secondary hyperparathyroidism. Treatment with active 1,25-dihydroxyvitamin D or its analogs can treat this condition in advanced or end-stage kidney disease. Few trials are available that define optimal treatment doses, biochemical targets, and long-term health impacts.
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Sex steroids, comprising of the androgens, estrogens, and progestogens, are fundamentally important to the development of muscle, bone, and fat across the life course. Each has roles that differ between these tissues, the male and female sexes, and developmental stage. It is the differential production of sex steroids and expression of their receptors that mediates much of the pubertal development in muscle, bone, and fat, which in turn determines the typical dimorphic sexual phenotypes. It is similar to how this differential production changes over time that is responsible for much of the typical sex-specific changes seen with normal aging. This chapter considers the sex-specific production of sex steroids and their effects upon each muscle, bone, and fat. It additionally covers the developmental changes in sex steroid production, and how this contributes to age-related changes in these three tissues.
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Background: Most elderly age groups in Indonesia experience vitamin D deficiency. Increasing age and decreasing food intake of vitamin D will trigger an increase in metabolic diseases. One of the most common effects of metabolic diseases is obesity. Unhealthy diet can reduce consumption of foods that contain sources of vitamin D. The suitability of diet in preventing vitamin D deficiency is influenced by the level of knowledge about the type of food, benefits and needs about vitamin D. Objectives: To analyze the relationship of vitamin D diet in older people with obesity to the level of knowledge of vitamin D.Methods: This was analytic observational study with case control design. Data collection technique was using purposive sampling. The sample in this research were geriatric with obesity and non-obesity. Subjects in each group were 88 elderly people according to inclusion and exclusion criteria. Instruments in this research were Food Frequency Questionnaire (FFQ) and questionnaire knowledge of vitamin D amounted to 11 questions that have been done validity (r> 0.361) and reliability (Cronbach's Alpha> 0.6). Chi Square test was used to compare age factor with food intake and vitamin D knowledge. Results: There was significant relationship between the level of knowledge and the pattern of vitamin D intake in old age (r = 0.293; p = 0.000). However there was no difference between intake patterns and level of knowledge on vitamin D in elderly obese and non-obese (p> 0.05).Conclusion: increased in vitamin D knowledge can improve food intake patterns in geriatric.ABSTRAKLatar Belakang: Kelompok usia lanjut di indonesia sebagian besar mengalami defisiensi vitamin D. Pertambahan usia dan penurunan asupan makanan vitamin D akan memicu peningkatan penyakit metabolik. Salah satu dampak penyakit metabolik yang paling sering terjadi adalah obesitas. Pola makan yang tidak sesuai dapat menurunkan konsumsi makanan yang mengandung sumber vitamin D. Kesesuaian pola makan dalam mencegah defisiensi vitamin D salah satunya dipengaruhi oleh tingkat pengetahuan mengenai jenis makanan, manfaat dan kebutuhan tubuh akan vitamin D.Tujuan: Melihat hubungan pola makan dan pengetahuan vitamin D pada usia lanjut dengan obesitas.Metode: Penelitian ini adalah observational dengan desain case control. Teknik pengumpulan data menggunakan purposive sampling. Sampel pada penelitian ini adalah masyarakat pada usia lanjut dengan obesitas dan non-obesitas. Subjek penelitian pada tiap kelompok berjumlah 88 orang yang memenuhi kriteria inklusi dan eksklusi. Instrumen pada penelitian ini adalah Food Frequency Questionnaire (FFQ) dan kuisioner pengetahun vitamin D berjumlah 11 soal yang telah dilakukan validitas (r>0,361) dan reliabilitas (Cronbach’s Alpha > 0,6). Uji Chi Square digunakan untuk melihat hubungan pola makan vitamin D dan tingkat pengetahuan pada usia lanjut dengan obesitas dan non-obesitas.Hasil: Adanya hubungan tingkat pengetahuan dan pola asupan vitamin D pada usia lanjut (r=0,293; p=0,000). Namun tidak terdapat perbedaan antara pola asupan dan tingkat pengetahuan terhadap vitamin D pada lansia obesitas dan non obesitas (p>0,05).Kesimpulan: Peningkatan pengetahuan tentang vitamin D dapat memperbaiki pola asupan makanan pada usia lanjut.
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Osteosarcopenia is a growing healthcare challenge. This is compounded by a lack of pharmacological strategies to treat both muscle and bone simultaneously. While there are no approved medications for osteosarcopenia, there are some compounds that are known to have a dual role in the treatment of muscle and bone. This chapter discusses the relevant literature, the efficacy, and the challenges surrounding these agents, as well as identifying avenues of future research. Agents of the androgen and endocrine axes repurposed antifracture medications, and factors involved in the crosstalk in muscle and bone are discussed. While there are a number of promising opportunities for future research, as yet there is no clear front-runner in the race to a treatment. More research into the relationship between muscle and bone is required to identify key components of their intertwined physiologies in order to identify the critical factors and pathways that might regulate the disease.
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Background: Vitamin D is considered an important regulator of many metabolic processes in the body. Its deficiency was reported to associate with many pathological conditions, with contradicting reports on its role in dyslipidemia. Objectives: To evaluate the role of vitamin D (total and/or free) in improving dyslipidemia of type 2 diabetes mellitus (T2DM). Methods: Sixty-four patients with T2DM, and 73 apparently healthy normal subjects were enrolled in the study from March to October 2020. Their fasting blood glucose, glycated hemoglobin, HbA1c, and serum lipids (cholesterol, its fractions and triglycerides) were measured in addition to total and free vitamin D. Results: There was a significant negative correlation between total vitamin D and each of cholesterol and LDL-C in the diabetic group. The correlations between serum vitamin D and all other lipid parameters (HDL-C, VLDL-C and triglycerides) were non-significant in the diabetic group, while in the control groups none of serum lipids showed significant correlations with vitamin D. Conclusions: The significant negative association of vitamin D with total cholesterol and LDLC in the diabetics reveals the important action of vitamin D in reducing the atherogenic indices, and consequent reduction in the rate of atherosclerosis and cardiovascular disease or stroke.
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Background Ambient ultraviolet (UV) radiation has been increasing due to climate change. While this may result in adverse health consequences such as an increased incidence of skin cancer, UV radiation is also a source of vitamin D, which has been hypothesized to be protective for breast cancer risk. Methods Using a spatiotemporal kriging model, we estimated residential UV exposure levels for the enrollment addresses (2003–2009) of breast cancer-free women aged 35–74 years participating in the Sister Study and living in the contiguous United States (N = 48,450). Cox proportional hazards models were used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the risk associated with UV exposure levels (mW/m²) categorized in quintiles. We examined the association for breast cancer overall (invasive and ductal carcinoma in situ) and by estrogen receptor (ER) status of the tumor. We considered effect modification by regular (≥4 times/week) vitamin D supplement use. Results Over a median of 10.5 years of follow up, 3,510 incident breast cancer diagnoses were reported. We found no evidence of an association between living in areas with higher levels of UV radiation and overall breast cancer risk (HRQ5 vs. Q1 = 1.00, 95% CI: 0.90, 1.11). Higher UV levels were inversely associated with the risk of ER- breast cancer (HRQ5 vs. Q1 = 0.73, 95% CI: 0.55–0.99), but not ER+ (HR Q5 vs. Q1 = 1.04, 95% CI: 0.92–1.18). For ER- breast cancer, the inverse association was only evident in women who did not regularly take vitamin D supplements (HRQ5 vs. Q1 = 0.52, 95% CI: 0.33–0.81) compared with those who did regularly take vitamin D supplements (HRQ5 vs. Q1 = 1.02, 95% CI: 0.68–1.54; p-for-heterogeneity = 0.12). Conclusions The findings from this study support a role for UV exposure and vitamin D in the etiology of ER- breast cancer.
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Vitamin D is a group of fat-soluble sec steroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and multiple other biological effects. The most important compounds in human are vitamin D₃ and vitamin D₂. Vitamin D is essential for strong bones, because it helps the body use calcium from the diet. Vitamin D deficiency has been associated with rickets, a disease in which the bone tissue doesn't properly mineralize, leading to soft bones and skeletal deformities. A cross sectional study was conducted from 30th January 2021 to 30th June 2021 to evaluate adverse outcomes of Vitamin D level among 370 females of aged 20-60 years were recruited through non-probability convenient sampling technique from students and Faculty of Colleges and Universities in Lahore, Pakistan. The data was collected through a Semi-Structured Questionnaire. A total 370 participants were included age groups of female ranging from 20-60. Comparing age and level of Vitamin D was more common in reproductive age of females with more association in young females of 20 to 30 years. 81.9 % participants had general awareness regarding deficiency of vitamin D. 80% People eat Vitamin D Rich Diet While only 20% use vitamin D supplements and only 41.9 % females drinks a Cup of Cow Milk. 73.8% participants had suffered weakness and general body aches and 82.2% females reported musculoskeletal pain. This study evaluated that Most of Educated People are unaware of Vitamin D knowledge and intake. They take insufficient amount of Vitamin D and experience discomfort in Muscoskeletal system.
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Periprosthetic joint infection (PJI) poses high morbidity as well as costs to the healthcare system. Evidence-based review of literature has highlighted the following modifiable risk factors as affecting rates of PJI—glycemic control, obesity, malnutrition, smoking, Vitamin D, preoperative Staphylococcus aureus screening, management of antirheumatic medications, urinary tract infection, oral health, appropriate antibiotic prophylaxis—as important variables to optimize to improve rates of PJI. Using the best available evidence, the authors have developed a practical approach for treating surgeons to optimize modifiable risk factors that can be improved upon in order to help minimize the risk of PJI.
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Human colorectal cancer cells not only express the nuclear vitamin D receptor (VDR) but are also endowed with 25-hydroxy-vitamin D3-1α-hydroxylase activity and therefore are able to produce the specific ligand for the VDR, the hormonally active steroid 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3). In the present study we show by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) as well as by Western blotting and immunohistochemical methods, that in human large intestinal carcinomas expression of the genes encoding the 25-(OH)D3-1α-hydroxylase as well as the VDR increases in parallel with ongoing dedifferentiation in the early phase of cancerogenesis, whereas in poorly differentiated late stage carcinomas only low levels of the respective mRNAs can be detected. This indicates that, through up-regulation of this intrinsic 1α,25(OH)2D3/VDR system which mediates the anti-mitotic effects of the steroid hormone, colorectal cancer cells are apparently able to increase their potential for an autocrine counter-regulatory response to neoplastic cell growth, particularly in the early stages of malignancy.
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Type 2 diabetes is a major public health problem, accounting for significant premature mortality and morbidity. The growth in prevalence of the condition appears to be closely linked with obesity. Over the last 5 years, a number of large observational studies have suggested an association between the onset of type 2 diabetes and Vitamin D deficiency. Vitamin D has important effects on insulin action, and may impact on a number of pathways which may be of importance in the development of type 2 diabetes. This article reviews the evidence linking Vitamin D deficiency in the pathogenesis of type 2 diabetes, and suggests areas for urgent further research to determine whether Vitamin D replacement has a role in the prevention of type 2 diabetes.
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Few studies have examined vitamin D insufficiency in African American men although they are at very high risk. We examined the prevalence and correlates of vitamin D insufficiency among African American men in Philadelphia. Participants in this cross-sectional analysis were 194 African American men in the Philadelphia region who were enrolled in a risk assessment program for prostate cancer from 10/96-10/07. All participants completed diet and health history questionnaires and provided plasma samples, which were assessed for 25-hydroxyvitamin D (25(OH)D) concentrations. We used linear regression models to examine associations with 25(OH)D concentrations and logistic regression to estimate odds ratios (OR) for having 25(OH)D >or= 15 ng/mL. Mean 25(OH)D was 13.7 ng/mL, and 61% of men were classified as having vitamin D insufficiency (25(OH)D <15 ng/mL). Even among men with vitamin D intake >or= 400 IU/day, 55% had 25(OH)D concentrations <15 ng/mL. In multivariate models, 25(OH)D concentrations were significantly associated with supplemental vitamin D intake (OR 4.3, 95% confidence interval (CI) 1.5, 12.4) for >400 vs. 0 IU/day), milk consumption (OR 5.9, 95% CI 2.2, 16.0 for >or= 3.5 vs. <1 time per week), and blood collection in the summer. Additionally, 25(OH)D concentrations increased with more recreational physical activity (OR 1.3, 95% CI 1.1, 1.6 per hour). A significant inverse association of body mass index with 25(OH)D concentrations in bivariate analyses was attenuated with adjustment for season of blood collection. The problem of low vitamin D status in African American men may be more severe than previously reported. Future efforts to increase vitamin D recommendations and intake, such as through supplementation, are warranted to improve vitamin D status in this particularly vulnerable population.
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Vitamin D deficiency is a highly prevalent condition, present in approximately 30% to 50% of the general population. A growing body of data suggests that low 25-hydroxyvitamin D levels may adversely affect cardiovascular health. Vitamin D deficiency activates the renin-angiotensin-aldosterone system and can predispose to hypertension and left ventricular hypertrophy. Additionally, vitamin D deficiency causes an increase in parathyroid hormone, which increases insulin resistance and is associated with diabetes, hypertension, inflammation, and increased cardiovascular risk. Epidemiologic studies have associated low 25-hydroxyvitamin D levels with coronary risk factors and adverse cardiovascular outcomes. Vitamin D supplementation is simple, safe, and inexpensive. Large randomized controlled trials are needed to firmly establish the relevance of vitamin D status to cardiovascular health. In the meanwhile, monitoring serum 25-hydroxyvitamin D levels and correction of vitamin D deficiency is indicated for optimization of musculoskeletal and general health.
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Recent reports of rickets among African American children drew attention to the vitamin D status of these infants and their mothers. African American women are at higher risk of vitamin D deficiency than are white women, but few studies have examined determinants of hypovitaminosis D in this population. We examined the prevalence and determinants of hypovitaminosis D among African American and white women of reproductive age. We examined 1546 African American women and 1426 white women aged 15-49 y who were not pregnant and who participated in the third National Health and Nutrition Examination Survey (1988-1994). Hypovitaminosis D was defined as a serum 25-hydroxyvitamin D concentration < or =37.5 nmol/L. Multiple logistic regression was used to examine the independent association of dietary, demographic, and behavioral determinants of hypovitaminosis D. The prevalence of hypovitaminosis D was 42.4 +/- 3.1% ( +/- SE) among African Americans and 4.2 +/- 0.7% among whites. Among African Americans, hypovitaminosis D was independently associated with consumption of milk or breakfast cereal <3 times/wk, no use of vitamin D supplements, season, urban residence, low body mass index, and no use of oral contraceptives. Even among 243 African Americans who consumed the adequate intake of vitamin D from supplements (200 IU/d), 28.2 +/- 2.7% had hypovitaminosis D. The high prevalence of hypovitaminosis D among African American women warrants further examination of vitamin D recommendations for these women. The determinants of hypovitaminosis D among women should be considered when these women are advised on dietary intake and supplement use.
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Although the role of vitamin D in type 2 diabetes is well recognized, its relation to glucose metabolism is not well studied. We investigated the relation of 25-hydroxyvitamin D [25(OH)D] concentrations to insulin sensitivity and beta cell function. We enrolled 126 healthy, glucose-tolerant subjects living in California. Insulin sensitivity index (ISI) and first- and second-phase insulin responses (1stIR and 2ndIR) were assessed by using a hyperglycemic clamp. Univariate regression analyses showed that 25(OH)D concentration was positively correlated with ISI (P < 0.0001) and negatively correlated with 1stIR (P = 0.0045) and 2ndIR (P < 0.0001). Multiple regression analyses confirmed an independent correlation between 25(OH)D concentration and ISI (P = 0.0007). No independent correlation was observed between 25(OH)D concentration and 1stIR or 2ndIR. However, an independent negative relation of 25(OH)D concentration with plasma glucose concentration was observed at fasting (P = 0.0258), 60 min (P = 0.0011), 90 min (P = 0.0011), and 120 min (P = 0.0007) during the oral-glucose-tolerance test. Subjects with hypovitaminosis D (<20 ng/mL) had a greater prevalence of components of metabolic syndrome than did subjects without hypovitaminosis D (30% compared with 11%; P = 0.0076). The data show a positive correlation of 25(OH)D concentration with insulin sensitivity and a negative effect of hypovitaminosis D on beta cell function. Subjects with hypovitaminosis D are at higher risk of insulin resistance and the metabolic syndrome. Further studies are required to explore the underlying mechanisms.
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Vitamin D has captured attention as an important determinant of bone health, but there is no common definition of optimal vitamin D status. Herein, we address the question: What is the optimal circulating level of 25-hydroxyvitamin D [25(OH)D] for the skeleton? The opinions of the authors on the minimum level of serum 25(OH)D that is optimal for fracture prevention varied between 50 and 80 nmol/l. However, for five of the six authors, the minimum desirable 25(OH)D concentration clusters between 70 and 80 nmol/l. The authors recognize that the average older man and woman will need intakes of at least 20 to 25 mcg (800 to 1,000 IU) per day of vitamin D(3 )to reach a serum 25(OH)D level of 75 nmol/l. Based on the available evidence, we believe that if older men and women maintain serum levels of 25(OH)D that are higher than the consensus median threshold of 75 nmol/l, they will be at lower risk of fracture.
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Accumulating research suggests that circulating concentrations of vitamin D may be inversely related to the prevalence of diabetes (1-4), to the concentration of glucose (4-8), and to insulin resistance (4,5,8,9). In addition, vitanim D deficiency may be a risk factor for the metabolic syndrome (8,10), a highly prevalent condition among U.S. adults (11). Much remains to be learned, however, about the relationship between vitamin D status and metabolic syndrome. Because this topic has received scant attention and the available information was derived from a small clinically based sample, we sought to examine the nature and strength of the association between serum concentrations of vitamin D and the metabolic syndrome in a large nationally representative sample of the U.S. population.
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Recent evidence suggests that vitamin D intakes above current recommendations may be associated with better health outcomes. However, optimal serum concentrations of 25-hydroxyvitamin D [25(OH)D] have not been defined. This review summarizes evidence from studies that evaluated thresholds for serum 25(OH)D concentrations in relation to bone mineral density (BMD), lower-extremity function, dental health, and risk of falls, fractures, and colorectal cancer. For all endpoints, the most advantageous serum concentrations of 25(OH)D begin at 75 nmol/L (30 ng/mL), and the best are between 90 and 100 nmol/L (36-40 ng/mL). In most persons, these concentrations could not be reached with the currently recommended intakes of 200 and 600 IU vitamin D/d for younger and older adults, respectively. A comparison of vitamin D intakes with achieved serum concentrations of 25(OH)D for the purpose of estimating optimal intakes led us to suggest that, for bone health in younger adults and all studied outcomes in older adults, an increase in the currently recommended intake of vitamin D is warranted. An intake for all adults of > or =1000 IU (25 microg) [DOSAGE ERROR CORRECTED] vitamin D (cholecalciferol)/d is needed to bring vitamin D concentrations in no less than 50% of the population up to 75 nmol/L. The implications of higher doses for the entire adult population should be addressed in future studies.
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Vitamin D deficiency, an important risk factor for osteoporosis and other chronic medical conditions, is epidemic in the United States. Uninsured women may be at an even higher risk for vitamin D deficiency than others owing to low intake of dietary and supplemental vitamin D and limited sun exposure. Our goal was to determine the prevalence of vitamin D deficiency in this vulnerable population. We enrolled 145 uninsured women at a County Free Medical Clinic in urban Michigan. Questionnaires were used to obtain information about demographics, medical history, vitamin supplementation, sunlight exposure, and dietary vitamin D intake. The 96 women who were tested for vitamin D status ranged in age from 21 to 65 years (mean 48 +/- 11), and 67% were vitamin D deficient as indicated by a 25-hydroxyvitamin D [25(OH)D)] level <50 nmol/L (20 ng/mL). Non-Caucasians were 3 times more likely than Caucasians to be vitamin D deficient (P = .049). Mean dietary vitamin D intake was low (125 +/- 109 IU/d) and only 24% of the participants used any supplemental vitamin D. Participants with total vitamin D intake <400 IU/day from diet and supplements were 10 times more likely to be vitamin D deficient than others (P < .001). These results demonstrate a high prevalence of vitamin D deficiency in an uninsured, medically underserved female population. Uninsured women should be strongly encouraged to increase their vitamin D intake.
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Vitamin D deficiency or insufficiency has been observed among populations in the northern United States. However, data on the prevalence of vitamin D deficiency in areas of high sun exposure, such as Arizona, are limited. The purpose of this study was to analyze serum 25-hydroxyvitamin D [25(OH)D] concentrations in residents of southern Arizona and to evaluate predictors of 25(OH)D in this population. Cross-sectional analyses of serum from participants in a colorectal adenoma prevention study were conducted to determine rates of vitamin D deficiency. Participants were categorized into 4 groups on the basis of serum 25(OH)D concentrations: <10.0 ng/mL, > or =10.0 ng/mL and <20.0 ng/mL, > or =20.0 ng/mL and <30.0 ng/mL, and > or =30.0 ng/mL. The mean serum 25(OH)D concentration for the total population was 26.1 +/- 9.1 ng/mL. Of 637 participants, 22.3% had 25(OH)D concentrations >30 ng/mL, 25.4% had concentrations <20 ng/mL, and 2.0% had concentrations <10 ng/mL. Blacks (55.5%) and Hispanics (37.6%) were more likely to have deficient 25(OH)D concentrations (<20 ng/mL) than were non-Hispanic whites (22.7%). Sun exposure had a greater effect on 25(OH)D in whites than in blacks and Hispanics, whereas BMI appeared to be more important in the latter groups. Despite residing in a region with high chronic sun exposure, adults in southern Arizona are commonly deficient in vitamin D deficiency, particularly blacks and Hispanics.
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There are few data on the skeletal health of Hispanic men. We observed differences in vitamin D deficiency and low BMD between Hispanic ethnic subgroups that persisted with adjustment for risk factors. Our data indicate a substantial burden of low BMD and vitamin D deficiency among Hispanic men. Disparities within ethnic groups are generally ignored, but in evolving populations they may have implications for public health. We examined ethnic variation in serum 25-hydroxyvitamin D [25(OH)D] and bone mineral density (BMD) among Hispanic American men. Three hundred and fifty-eight Hispanic males 30 to 79 years of age were studied. Logistic regression models assessed variation in odds of vitamin D deficiency (<20 ng/mL) and low BMD (T-score<-1) by ethnicity, with and without adjustment for risk factors (age, smoking, occupation, physical activity, body mass index, and sunlight exposure). Vitamin D deficiency was most common among Puerto Rican (26%), compared with Dominican (21%), Central American (11%), and South American (9%) men. Percentages with low BMD were: South American (44%), Puerto Rican (34%), Dominican (29%), and Central American (23%). Adjustment for age and risk factors failed to account for Hispanic subgroup differences in vitamin D deficiency and low BMD. Population estimates indicate a substantial burden of low BMD and vitamin D deficiency among Hispanic men. Our findings underscore the importance of examining the skeletal health of Hispanic subgroups, and suggest that a considerable number of Hispanic men may be at elevated risk of fracture and vitamin D deficiency.
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Background: In cross-sectional studies, low serum levels of 25-hydroxyvitamin D are associated with higher prevalence of cardiovascular risk factors and disease. This study aimed to determine whether endogenous 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels are related to all-cause and cardiovascular mortality. Methods: Prospective cohort study of 3258 consecutive male and female patients (mean [SD] age, 62 [10] years) scheduled for coronary angiography at a single tertiary center. We formed quartiles according to 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels within each month of blood drawings. The main outcome measures were all-cause and cardiovascular deaths. Results: During a median follow-up period of 7.7 years, 737 patients (22.6%) died, including 463 deaths from cardiovascular causes. Multivariate-adjusted hazard ratios (HRs) for patients in the lower two 25-hydroxyvitamin D quartiles (median, 7.6 and 13.3 ng/mL [to convert 25-hydroxyvitamin D levels to nanomoles per liter, multiply by 2.496]) were higher for all-cause mortality (HR, 2.08; 95% confidence interval [CI], 1.60-2.70; and HR, 1.53; 95% CI, 1.17-2.01; respectively) and for cardiovascular mortality (HR, 2.22; 95% CI, 1.57-3.13; and HR, 1.82; 95% CI, 1.29-2.58; respectively) compared with patients in the highest 25-hydroxyvitamin D quartile (median, 28.4 ng/mL). Similar results were obtained for patients in the lowest 1,25-dihydroxyvitamin D quartile. These effects were independent of coronary artery disease, physical activity level, Charlson Comorbidity Index, variables of mineral metabolism, and New York Heart Association functional class. Low 25-hydroxyvitamin D levels were significantly correlated with variables of inflammation (C-reactive protein and interleukin 6 levels), oxidative burden (serum phospholipid and glutathione levels), and cell adhesion (vascular cell adhesion molecule 1 and intercellular adhesion molecule 1 levels). Conclusions: Low 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels are independently associated with all-cause and cardiovascular mortality. A causal relationship has yet to be proved by intervention trials using vitamin D.
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The decline in vitamin D status among older people is probably due to decreased synthesis of vitamin D by sun-exposed skin and/or decreased outdoor activity. The authors examined the association between outdoor leisure physical activity and serum 25-hydroxyvitamin D in the Third National Health and Nutrition Examination Survey (1988-1994) (n = 15,148 aged >/=20 years). The mean 25-hydroxyvitamin D concentration declined with increasing age, with 79, 73, and 68 nmol/liter for persons aged 20-39, 40-59, and 60 or more years. The proportion that engaged in outdoor activity in the past month was 80% for persons aged 20-39 and 40-59 years but 71% for those aged 60 or more years. In contrast, the mean difference in 25-hydroxyvitamin D between those who participated in outdoor activities daily compared with those who did not participate in the past month was similar for the youngest and oldest age groups: 13 and 16 nmol/liter, respectively. Those persons aged 60 or more years who participated in daily outdoor activities had a mean 25-hydroxyvitamin D concentration similar to that of persons aged 20-39 years: 77 versus 79 nmol/liter, respectively. These nationally representative data suggest that persons aged 60 or more years can synthesize enough vitamin D from daily outdoor activities to maintain vitamin D levels similar to those of young adults.
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Vitamin D insufficiency has now reached epidemic proportions and has been linked to increased body fat and decreased muscle strength. Whether vitamin D insufficiency is also related to adipose tissue infiltration in muscle is not known. The objective of the study was to examine the relationship between serum 25-hydroxyvitamin D (25OHD) and the degree of fat infiltration in muscle. This was a cross-sectional study. OUTCOME MEASURES AND SUBJECTS: Measures were anthropometric measures, serum 25OHD radioimmunoassay values, and computed tomography (CT) values of fat, muscle mass, and percent muscle fat in 90 postpubertal females, aged 16-22 yr, residing in California. Approximately 59% of subjects were 25OHD insufficient (< or = 29 ng/ml), of which 24% were deficient (< or = 20 ng/ml), whereas 41% were sufficient (> or = 30 ng/ml). A strong negative relationship was present between serum 25OHD and CT measures of percent muscle fat (r = -0.37; P < 0.001). In contrast, no relationship was observed between circulating 25OHD concentrations and CT measures of thigh muscle area (r = 0.16; P = 0.14). Multiple regression analysis indicated that the relation between 25OHD and muscle adiposity was independent of body mass or CT measures of sc and visceral fat. Percent muscle fat was significantly lower in women with normal serum 25OHD concentrations than in women with insufficient levels and deficient levels (3.15 +/- 1.4 vs. 3.90 +/- 1.9; P = 0.038). We found that vitamin D insufficiency is associated with increased fat infiltration in muscle in healthy young women.
Article
Changes in serum 25-hydroxyvitamin D [25(OH)D] concentrations in the US population have not been described. We used data from the National Health and Nutrition Examination Surveys (NHANES) to compare serum 25(OH)D concentrations in the US population in 2000-2004 with those in 1988-1994 and to identify contributing factors. Serum 25(OH)D was measured with a radioimmunoassay kit in 20 289 participants in NHANES 2000-2004 and in 18 158 participants in NHANES III (1988-1994). Body mass index (BMI) was calculated from measured height and weight. Milk intake and sun protection were assessed by questionnaire. Assay differences were assessed by re-analyzing 150 stored serum specimens from NHANES III with the current assay. Age-adjusted mean serum 25(OH)D concentrations were 5-20 nmol/L lower in NHANES 2000-2004 than in NHANES III. After adjustment for assay shifts, age-adjusted means in NHANES 2000-2004 remained significantly lower (by 5-9 nmol/L) in most males, but not in most females. In a study subsample, adjustment for the confounding effects of assay differences changed mean serum 25(OH)D concentrations by approximately 10 nmol/L, and adjustment for changes in the factors likely related to real changes in vitamin D status (ie, BMI, milk intake, and sun protection) changed mean serum 25(OH)D concentrations by 1-1.6 nmol/L. Overall, mean serum 25(OH)D was lower in 2000-2004 than 1988-1994. Assay changes unrelated to changes in vitamin D status accounted for much of the difference in most population groups. In an adult subgroup, combined changes in BMI, milk intake, and sun protection appeared to contribute to a real decline in vitamin D status.
Article
To determine the effect of increased skin pigment on the cutaneous production of vitamin D3, circulating vitamin D concentrations were determined in two lightly pigmented Caucasian and three heavily pigmented Negro volunteers after exposure to a single standard dose of ultraviolet radiation (UVR). Exposure of Caucasian subjects to 1 minimal erythemal dose of UVR greatly increased serum vitamin-D concentrations by up to 60-fold 24-48 h after exposure, whereas this dose did not significantly change serum vitamin-D concentrations in Negro subjects. Re-exposure of one Negro subject to a dose of UVR six times larger than the standard dose increased circulating vitamin D to concentrations similar to those recorded in Caucasian subjects after exposure to the lower dose. These results indicate that increased skin pigment can greatly reduce the UVR-mediated synthesis of vitamin D.
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A previous study has shown that serum levels of the active vitamin D metabolite 1,25-(OH)2-vitamin D were inversely related to blood pressure levels while the prohormone 25-OH-vitamin D was found to be related to insulin metabolism. Also other clinical and experimental data support the view that vitamin D metabolism is involved in blood pressure regulation and other metabolic processes. The present study was conducted in order to see if the above mentioned relationships between the vitamin D endocrine system and blood pressure, as well as other cardiovascular risk factors, could be found in a cross-section population-based study. Serum levels of 1,25-(OH)2-vitamin D, 25-OH-vitamin D, and blood pressure were therefore measured in 34 middle-aged men and metabolic cardiovascular risk factors were evaluated by means of intravenous glucose and fat tolerance tests, euglycemic hyperinsulinemic clamp, lipoprotein measurements, and lipoprotein lipase activity determinations. Serum levels of 1,25-(OH)2-vitamin D were found to be inversely correlated to the blood pressure (r = -0.42, P < .02), VLDL triglycerides (r = -0.47, P < .005), and to triglyceride removal at the intravenous fat tolerance test (r = 0.34, P < .05), while serum levels of 25-OH-vitamin D were correlated to fasting insulin (r = -0.35, P < .05), insulin sensitivity during clamp (r = 0.54, P < .001), and lipoprotein lipase activity both in adiposal tissue (r = 0.48, P < .005) and skeletal muscle (r = 0.38, P < .03). These findings highlight the question for a role of vitamin D metabolism and intake in a metabolic syndrome involving hypertension as well as hyperlipidemia and insulin resistance. Am J Hypertens 1995;8:894–901
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The activated form of vitamin D, 1,25(OH)2D3, and its analogues can prevent type I diabetes in NOD mice. Protection is achieved without signs of systemic immunosuppression and is associated with a restoration of the defective immune regulator system of the NOD mice. The aim of the present study was to investigate whether this restoration of regulator cell function is the only mechanism in the prevention of diabetes by 1,25(OH)2D3. We tested therefore if 1,25(OH)2D3 could prevent cyclophosphamide-induced diabetes, since diabetes occurring after cyclophosphamide injection is believed to be due to an elimination of suppresser cells. NOD mice treated with 1,25(OH)2D3 (5 microg/kg every 2 days) from the time of weaning were clearly protected against diabetes induced by cyclophosphamide (200 mg/kg body wt at 70 days old) (2/12 (17%) versus 36/53 (68%) in control mice, P < 0.005). By co-transfer experiments it was demonstrated that cyclophosphamide had indeed eliminated the suppresser cells present in 1,25(OH)2D3-treated mice. Since cyclophosphamide injection did not break the protection offered by 1,25(OH)2D3, it was clear that diabetogenic effector cells were affected by 1,25(OH)2D3 treatment as well. This was confirmed by the finding that splenocytes from 1,25(OH)2D3-treated mice were less capable of transferring diabetes in young, irradiated NOD mice, and by the demonstration of lower Th1 cytokine levels in the pancreases of 1,25(OH)2D3-treated, cyclophosphamide-injected mice. This better elimination of effector cells in 1,25(OH)2D3-treated mice could be explained by a restoration of the sensitivity to cyclophosphamide-induced apoptosis in both thymocytes and splenocytes, in normally apoptosis-resistant NOD mice. Altogether, these data indicate that the protection against diabetes offered by 1,25(OH)2D3 may be independent of the presence of suppresser cells, and may involve increased apoptosis of Th1 autoimmune effector cells.
Article
We analyzed data from the first National Health and Nutrition Examination Survey Epidemiologic Follow-up Study to test the hypothesis that vitamin D from sunlight exposure, diet, and supplements reduces the risk of breast cancer. We identified 190 women with incident breast cancer from a cohort of 5009 white women who completed the dermatological examination and 24-h dietary recall conducted from 1971-1974 and who were followed up to 1992. Using Cox proportional hazards regression, we estimated relative risks (RRs) for breast cancer and 95% confidence intervals, adjusting for age, education, age at menarche, age at menopause, body mass index, alcohol consumption, and physical activity. Several measures of sunlight exposure and dietary vitamin D intake were associated with reduced risk of breast cancer, with RRs ranging from 0.67-0.85. The associations with vitamin D exposures, however, varied by region of residence. The risk reductions were highest for women who lived in United States regions of high solar radiation, with RRs ranging from 0.35-0.75. No reductions in risk were found for women who lived in regions of low solar radiation. Although limited by the relatively small size of the case population, the protective effects of vitamin D observed in this prospective study are consistent for several independent measures of vitamin D. These data support the hypothesis that sunlight and dietary vitamin D reduce the risk of breast cancer.
Article
Prostate cancer is the second leading cause of cancer deaths in men in the United States. Developing new treatment strategies is critical to improving the health of men. This article will be a general review of the field with a focus on research from our laboratory. Our research has focused on four areas in which we have pursued the possible use of 1alpha,25(OH)(2)D(3) and its analogs to treat prostate cancer: 1) The ability of 1alpha,25(OH)(2)D(3) to up-regulate androgen receptors in LNCaP human prostate cancer cells. The implications of this finding on 1alpha,25(OH)(2)D(3)'s ability to inhibit cell growth in vivo are unclear at present.2) The reasons for an inability of 1alpha,25(OH)(2)D(3) to inhibit DU 145 prostate cancer cell growth were explored. We found that combination of an imidazole drug, Liarozole, with 1alpha,25(OH)(2)D(3) was capable of inhibiting DU 145 cell growth.3) A number of low-calcemic vitamin D analogs exhibit potent anti-proliferative activity on prostate cancer cells. We have developed a novel approach using the yeast two-hybrid system to screen for potent analogs.4) The results of a clinical trial of 1alpha,25(OH)(2)D(3) treatment of patients with early recurrent prostate cancer. We provide preliminary evidence that 1alpha,25(OH)(2)D(3) may be effective in slowing the rate of PSA rise in selected cases of prostate cancer. In conclusion, we believe that 1alpha,25(OH)(2)D(3) has a role in the treatment and/or prevention strategies being developed for prostate cancer. However, to increase antiproliferative potency without increasing side-effects, the use of less calcemic analogs appears to be the most reasonable approach.
Article
Long-term vitamin D insufficiency can cause secondary hyperparathyroidism and osteomalacia (1). In addition, there is increasing evidence that vitamin D may protect against common cancers, such as cancer of the colon (2–4), prostate (5), and breast (6). Young adults aged 17 to 35 years drink inadequate amounts of milk (7) and are concerned about exposure to the sun because of the fear of developing skin cancer (8,9), which increases the risk of vitamin D insufficiency (10). We sought to examine the prevalence of vitamin D insufficiency in a group of free-living healthy young adults, consisting of mostly health care professionals, in Boston, Massachusetts.
Article
To assess the relative costs and benefits of calcium and vitamin D supplements, cyclic etidronate, or alendronate in the prevention of vertebral fractures for women and with normal bone density and osteopenia who are about to initiate moderate dose glucocorticoid treatment. Using a decision analysis model, we evaluated the following patients: 4 hypothetical cohorts: 30-yr-old women with normal lumbar spine (LS) bone mineral density (BMD) (t score = 0), 50-yr-old women with borderline osteopenia (t score = -1), 60-yr-old women with moderate osteopenia (t score = -1.5), and 70-yr-old women with severe osteopenia (t score = -2) treated with a mean prednisone dose of 10 mg/day for one year. The main outcomes included the development of vertebral fractures 10 years after glucocorticoid treatment and at age 80 (life-time risk) and direct and indirect costs. At 10 years, calcium and vitamin D supplements decreased fracture rates by 30-50% at a minimal cost (US$800 or less per vertebral fracture avoided) or at a cost saving compared to no treatment for women with osteopenia (t score -1 to -2). Etidronate and alendronate are most cost effective in women with borderline osteoporosis (t scores of -1.5 and -2) in the 10 year analysis. In the life-time analysis, calcium and vitamin D treatment yielded a cost savings compared to no treatment for all groups with osteopenia. Etidronate decreased fracture rates further in all groups at a cost of less than $2,000 per fracture prevented. Alendronate reduced the fracture risk further at cost of $3,000-7,000 per fracture avoided. Calcium and vitamin D supplements and low cost bisphosphonate regimens such as cyclic etidronate decrease the life-time vertebral fracture risk at acceptable costs and should be considered when initiating glucocorticoid treatment for women who do not have osteoporosis.
Article
The renin-angiotensin system (RAS) plays a central role in the regulation of blood pressure, electrolyte, and volume homeostasis. Epidemiological and clinical studies have long suggested an association of inadequate sunlight exposure or low serum 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] levels with high blood pressure and/or high plasma renin activity, but the mechanism is not understood. Our recent discovery that 1,25(OH)(2)D(3) functions as a potent negative endocrine regulator of renin gene expression provides some insights into the mechanism. The concept of vitamin D regulation of blood pressure through the RAS opens a new avenue to our understanding of the physiological functions of the vitamin D endocrine system, and provides a basis for exploring the potential use of vitamin D analogues in prevention and treatment of hypertension.
Article
This study was designed to evaluate the association between vitamin D status and congestive heart failure (CHF). Impaired intracellular calcium metabolism is an important factor in the pathogenesis of CHF. The etiology of CHF, however, is not well understood. Twenty patients age <50 years and 34 patients age >/=50 years with New York Heart Association classes >/=2 and 34 control subjects age >/=50 years were recruited. N-terminal pro-atrial natriuretic peptide (NT-proANP), a predictor of CHF severity; vitamin D metabolites; and parameters of calcium metabolism were measured in fasting blood samples collected between November 2000 and March 2001. Both groups of CHF patients had markedly increased serum levels of NT-proANP (p < 0.001), increased serum phosphorus levels (p < 0.001), and reduced circulating levels of both 25-hydroxyvitamin D (p < 0.001) and calcitriol (p < 0.001). Albumin-corrected calcium levels were reduced and parathyroid hormone levels were increased in the younger CHF patients compared with the controls (both p values <0.001). Moreover, parathyroid hormone levels tended to be higher in the elderly CHF patients than in the controls (p = 0.074). In a nonlinear regression analysis 25-hydroxyvitamin D and calcitriol were inversely correlated with NT-proANP (r(2) = 0.16; p < 0.001 and r(2) = 0.12; p < 0.01, respectively). The vitamin D genotype at the BmsI restriction site did not differ between the study groups. The low vitamin D status can explain alterations in mineral metabolism as well as myocardial dysfunction in the CHF patients, and it may therefore be a contributing factor in the pathogenesis of CHF.
Article
Human prostate cells contain receptors for 1alpha,25-dihydroxyvitamin D, the active form of vitamin D. Prostate cancer cells respond to vitamin D(3) with increases in differentiation and apoptosis, and decreases in proliferation, invasiveness and metastasis. These findings strongly support the use of vitamin D-based therapies for prostate cancer and/or as a second-line therapy if androgen deprivation fails. The association between either decreased sun exposure or vitamin D deficiency and the increased risk of prostate cancer at an earlier age, and with a more aggressive progression, indicates that adequate vitamin D nutrition should be a priority for men of all ages. Here we summarize recent advances in epidemiological and biochemical studies of the endocrine and autocrine systems associated with vitamin D and their implications for prostate cancer and in the evaluation of vitamin D(3) and its analogs in preventing and/or treating prostate cancer.
Article
Vitamin D is a potent regulator of calcium homeostasis and may have immunomodulatory effects. The influence of vitamin D on human autoimmune disease has not been well defined. The purpose of this study was to evaluate the association of dietary and supplemental vitamin D intake with rheumatoid arthritis (RA) incidence. We analyzed data from a prospective cohort study of 29,368 women of ages 55-69 years without a history of RA at study baseline in 1986. Diet was ascertained using a self-administered, 127-item validated food frequency questionnaire that included supplemental vitamin D use. Risk ratios (RRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards regression, adjusting for potential confounders. Through 11 years of followup, 152 cases of RA were validated against medical records. Greater intake (highest versus lowest tertile) of vitamin D was inversely associated with risk of RA (RR 0.67, 95% CI 0.44-1.00, P for trend = 0.05). Inverse associations were apparent for both dietary (RR 0.72, 95% CI 0.46-1.14, P for trend = 0.16) and supplemental (RR 0.66, 95% CI 0.43-1.00, P for trend = 0.03) vitamin D. No individual food item high in vitamin D content and/or calcium was strongly associated with RA risk, but a composite measure of milk products was suggestive of an inverse association with risk of RA (RR 0.66, 95% CI 0.42-1.01, P for trend = 0.06). Greater intake of vitamin D may be associated with a lower risk of RA in older women, although this finding is hypothesis generating.
Article
Vitamin D is very important for overall health and wellbeing. A major source of vitamin D comes from exposure to sunlight. Measurement of 25-hydroxyvitamin D in the blood and not 1,25-dihydroxyvitamin D is used to determine vitamin D status. A blood level of 25-hydroxyvitamin D of at least 20 ng/mL is considered to be vitamin D sufficient. Vitamin D deficiency increases the risk of many common cancers, multiple sclerosis, rheumatoid arthritis, hypertension, cardiovascular heart disease, and type I diabetes.
Article
During the past decade, major advances have been made in vitamin D research that transcend the simple concept that vitamin D is Important for the prevention of rickets in children and has little physiologic relevance for adults. Inadequate vitamin D, in addition to causing rickets, prevents children from attaining their genetically programmed peak bone mass, contributes to and exacerbates osteoporosis in adults, and causes the often painful bone disease osteomalacia. Adequate vitamin D is also important for proper muscle functioning, and controversial evidence suggests it may help prevent type 1 diabetes mellitus, hypertension, and many common cancers. Vitamin D inadequacy has been reported in approximately 36% of otherwise healthy young adults and up to 57% of general medicine inpatients in the United States and in even higher percentages in Europe. Recent epidemiological data document the high prevalence of vitamin D inadequacy among elderly patients and especially among patients with osteoporosis. Factors such as low sunlight exposure, age-related decreases in cutaneous synthesis, and diets low in vitamin D contribute to the high prevalence of vitamin D inadequacy. Vitamin D production from cutaneous synthesis or intake from the few vitamin D-rich or enriched foods typically occurs only intermittently. Supplemental doses of vitamin D and sensible sun exposure could prevent deficiency in most of the general population. The purposes of this article are to examine the prevalence of vitamin D inadequacy and to review the potential implications for skeletal and extraskeletal health.