ArticlePDF Available

Effect of Vitamin D Supplementation on Weight Loss, Glycemic Indices, and Lipid Profile in Obese and Overweight Women: A Clinical Trial Study

Authors:

Abstract

Introduction Vitamin D (vit D) deficiency has defined as a health problem worldwide. World Health Organization (WHO) has declared that obesity is an epidemic of the 21st century. Previous studies have shown that obesity may increase the risk of Vit D deficiency. Furthermore, other studies have demonstrated that vit D insufficiency was accompanied with higher risk of type 2 diabetes, cardiovascular diseases, hypertension, and obesity. The aim of this study was to survey the effect of vit D supplementation on weight loss among overweight and obese women aged 20–40 years in Isfahan. Methods This double-blind clinical trial was done on 50 overweight and obese women who were divided into two groups, in which one group received vit D supplements and the other group received placebo. Intervention group received vit D with dozes 50,000 IU/w for 6 weeks. The levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), fasting blood sugar (FBS), insulin (ins), homeostasis model assessment of ins resistance (IR), C-reactive protein (CRP), height, weight (WT), waist circumference (WC), hip circumference (HC), and blood pressure (BP) were measured before and after intervention. Results After using vit D supplementation for 6 weeks, WT, WC, and body mass index (BMI) were decreased significantly and serum vit D increased significantly compared to control group (P < 0.001). Other factors including TC, TG, LDL-c, HDL-c, FBS, CRP, ins, IR, and waist to hip ratio (WHR) did not change significantly (P > 0.05). Conclusions After 6 weeks of intervention, the means of WT, BMI, WC, and HC decreased significantly. Previous studies have shown that vit D deficiency was more prevalence in obese people and there was an inverse association among vit D with BMI and WC. The relationship between vit D and lipid profiles such as glycemic indexes, anthropometric indexes, CRP, and BP is not clear and needs more study in the future.
1© 2018 International Journal of Preventive Medicine | Published by Wolters Kluwer - Medknow
Introduction
Vitamin D (vit D) deciency is considered
as a health problem worldwide. Nowadays,
vit D deciency has involved more than
half of people worldwide.[1] The prevalence
of vit D deciency in Tehran and Isfahan
was estimated about 81/3% and 70/16%,
respectively.[2] vit D plays an important role
in calcium metabolism, maintenance of the
skeleton, control of cell proliferation and
differentiation, and immunity.[3] Recently,
it has been shown that vit D deciency
has a strong relationship with increased
risk of type 2 diabetes, cardiovascular
disease (CVD) as well as CVD risk
factors such as hypertension and
obesity.[4] Obesity was recognized as an
epidemic of the 21st century by World
Health Organization (WHO)[5] and it is a
serious health problem worldwide.[5,6] Since
Address for correspondence:
Dr. Mohammad Hasan Entezari,
Department of Clinical
Nutrition/Community
Nutrition/Food Science and
Technology, Food Security
Research Center, School of
Nutrition and Food Science,
Isfahan University of Medical
Sciences, Isfahan, Iran.
E‑mail: entezari@hlth.mui.ac.ir
Abstract
Introduction: Vitamin D (vit D) deciency has dened as a health problem worldwide. World
Health Organization (WHO) has declared that obesity is an epidemic of the 21st century. Previous
studies have shown that obesity may increase the risk of Vit D deciency. Furthermore, other studies
have demonstrated that vit D insufciency was accompanied with higher risk of type 2 diabetes,
cardiovascular diseases, hypertension, and obesity. The aim of this study was to survey the effect
of vit D supplementation on weight loss among overweight and obese women aged 20–40 years in
Isfahan. Methods: This double‑blind clinical trial was done on 50 overweight and obese women
who were divided into two groups, in which one group received vit D supplements and the other
group received placebo. Intervention group received vit D with dozes 50,000 IU/w for 6 weeks.
The levels of total cholesterol (TC), triglyceride (TG), low‑density lipoprotein cholesterol (LDL‑c),
high‑density lipoprotein cholesterol (HDL‑c), fasting blood sugar (FBS), insulin (ins), homeostasis
model assessment of ins resistance (IR), C‑reactive protein (CRP), height, weight (WT), waist
circumference (WC), hip circumference (HC), and blood pressure (BP) were measured before and
after intervention. Results: After using vit D supplementation for 6 weeks, WT, WC, and body mass
index (BMI) were decreased signicantly and serum vit D increased signicantly compared to control
group (P < 0.001). Other factors including TC, TG, LDL‑c, HDL‑c, FBS, CRP, ins, IR, and waist to
hip ratio (WHR) did not change signicantly (P > 0.05). Conclusions: After 6 weeks of intervention,
the means of WT, BMI, WC, and HC decreased signicantly. Previous studies have shown that vit
D deciency was more prevalence in obese people and there was an inverse association among vit
D with BMI and WC. The relationship between vit D and lipid proles such as glycemic indexes,
anthropometric indexes, CRP, and BP is not clear and needs more study in the future.
Keywords: Blood pressure, cholesterol, high‑density lipoprotein, low‑density lipoprotein,
triglyceride, Vitamin D supplementation, weight loss, glycemic indices
Effect of Vitamin D Supplementation on Weight Loss, Glycemic Indices,
and Lipid Prole in Obese and Overweight Women: A Clinical Trial Study
Original Article
Zahra Sadat
Khosravi,
Marzieh Kafeshani1,
Parastoo Tavasoli,
Akbar Hassan Zadeh2,
Mohammad Hassan
Entezari1
Departments of Clinical
Nutrition and 1Clinical
Nutrition/Community Nutrition/
Food Science and Technology,
Food Security Research Center,
School of Nutrition and Food
Science, Isfahan University of
Medical Sciences, Isfahan, Iran,
2Department of Epidemiology
and Biostatic, School of Health,
Isfahan University of Medical
Sciences, Isfahan, Iran
How to cite this article: Khosravi ZS, Kafeshani M,
Tavasoli P, Hassan Zadeh A, Entezari MH. Effect
of Vitamin D supplementation on weight loss,
glycemic indices, and lipid prole in obese and
overweight women: A clinical trial study. Int J Prev
Med 2018;9:63.
19th century, the prevalence of obesity has
increased along with changes in diets and
lifestyle factors.[7] WHO estimated that at
least 300 million adults are obese and more
than 1 billion are overweight worldwide.[7,8]
It is proved that 3.4 million of obese and
overweight people are died due to obesity
and comorbidities including hypertension,
type 2 diabetes, stroke, CVD, some type
of cancer such as prostate, breast, ovary,
cervix, colon, and gallbladder every
year.[5,9] In addition, obesity is related
with hypercholesterolemia, osteoarthritis,
gastroesophageal reux, sleep apnea, and
kidney chronic disease.[10] Furthermore, this
issue becomes a general health problem
In Iran. The prevalence of obesity and
overweight was 42% in men and 57% in
women in 2005, and it was anticipated
to reach 54% and 74% among men and
Access this article online
Website:
www.ijpvmjournal.net/www.ijpm.ir
DOI:
10.4103/ijpvm.IJPVM_329_15
Quick Response Code:
This is an open access arcle distributed under the terms of the
Creave Commons Aribuon‑NonCommercial‑ShareAlike 3.0
License, which allows others to remix, tweak, and build upon the
work non‑commercially, as long as the author is credited and the
new creaons are licensed under the idencal terms.
For reprints contact: reprints@medknow.com
[Downloaded free from http://www.ijpvmjournal.net on Friday, July 20, 2018, IP: 176.120.110.104]
Khosravi, et al.: Vitamin D supplementation, weight loss, glycemic indices, and lipid prole
International Journal of Preventive Medicine 2018, 9: 632
women, respectively by 2015.[11] A study In Iran showed
that obesity in women are more than twice than men.[12]
In a performed study in Isfahan, all women over than
65 years had abdominal obesity.[13] Lifestyle modication
such as proper exercise is the best and cheapest way for
decreasing the obesity. In addition, diet plays a key role in
weight loss programs.[7] Today’s attention toward the role
of vit D in chronic diseases such as obesity is increasing.
Based on several studies, obese and overweight people
mostly have a lower levels of vit D than those who have
less body fat.[14] Some studies suggested that obesity
increased risk of vit D deciency[15] whereas other studies
shown that insufcient levels of vit D could increase
the risk of type 2 diabetes, CVD, and risks such as
hypertension and obesity.[16] A previous study has shown
that vit D deciency is more common in obese people.
It was seen that there is an inverse association
among vit D with body mass index (BMI) and waist
circumference (WC).[4,17‑20] However, conicting results
had been seen such as a study among Iranian individuals
aged 20–64 years with BMI of 24.2 ± 3.8 (57% female)
which has not shown signicant association between
serum levels of vit D and BMI.[4] In this study, we tried
to perform a comprehensive assessment about the effects
of vit D supplementation and body weight as well as other
anthropometric measurements, BP, lipid prole, glycemic
indices, and C‑reactive protein (CRP) among Iranian
women. Therefore, our main purpose was to examine the
effect of vit D on weight loss in obese and overweight
women aged 20–40 years in Isfahan.
Methods
Subjects
This double‑blind clinical trial study was performed
among overweight and obese women in Isfahan
endocrine and metabolism center, and other participants
were female students of Isfahan University of Medical
Science. Convenient method was used to enroll
participants to the study. The following inclusion criteria
was used to select participants: 20–40 years females,
BMI higher than 25 (obese and overweight), nonsmoking,
no history of diabetes, no hyperthyroids and hypothyroids,
no participation in other weight loss programs, no weight
loss during two past months, regular menstrual cycle,
and no pregnancy. The general questionnaire included
information about demographic characteristics such as
location, education level, marital status and the number
of pregnancy and children. In addition, we asked other
questions about physical activity, the duration and times
of sleep, consumption of supplements, and being on a
special of diet. After giving general overview about this
study, all individuals provided informed written consent.
Study design
The aim of this double‑blind clinical trial study was to
evaluate the effect of vit D supplementation on weight
loss in 20–40 years obese and overweight women in
Isfahan. The enough sample size was 25 person in each
group that calculated according to the following formula
N = (z1+z2 2s²/d². In this formula, α was considered
0.05 and β was 80%. Hence, we recruited 75 persons to
compensate potential losses during 6 weeks at follow‑up.
After that, individuals were randomly divided into two
groups (intervention and control) and received vit D
supplements and placebo, respectively. The participants
continued their usual diet during the study. The
intervention follow‑up was 6 weeks that began from May
21, 2013 to July 5, 2013. At the rst visit, we gave 6 pearls
of vit D supplements to intervention group and 6 pearls of
placebo to the controls and we asked them to eat one per
week. Supplements were made in Zahravi pharmaceutical
company, Tabriz, Iran. The dozens of supplements were
50,000 IU and placebo had the same shape, color, and
packaging with given supplement. In addition, at the rst
meeting, food record has been explained to the individuals
and they were asked to prepare it for 3 days including one
weekend and 2 week days. Furthermore, the individuals
were asked to report their physical activity during one
selected week. In addition, participants recorded their
daily amount of sun exposure from sunrise till sunset.
The levels of total cholesterol (TC), triglyceride (TG),
low‑density lipoprotein cholesterol (LDL‑c), high‑density
lipoprotein cholesterol (HDL‑c), fasting blood
sugar (FBS), insulin (ins), homeostasis model assessment
of ins resistance (HOMA‑IR), CRP, vit D, height (ht),
WT, WC, blood pressure (BP), and BMI were measured
at the beginning and the end of study. Furthermore,
anthropometric indicators and BP were measured. ht
was measured by tape without shoes, nearest to the
0.1 cm, and for weight, we used a Beshel model digital
scale (Germany) nearest to the 0.1 kg that individuals
wore light clothing with no shoes. BMI was calculated
with this formula, BMI = weight (kg)/height² (m). BMI
between 24/9 and 29/9 was dened as overweight and
more than 29/9 was dened obese. Individuals’s BP
was measured by trained personnel using a mercury
sphygmomanometer, after 10 min of rest in a sitting
position.
Biochemical analysis
Blood samples were taken in a sitting position following
12–14 h overnight fasting before and after the intervention.
FBS, lipid proles, and CRP were measured by biochemical
autoanalyzer A15 with Biosystem kit (made by Spain).
ELISA method was used to determine concentration of vit
D and ins. In addition, we obtained the ins sensitivity with
using this formula: (fasting ins [micro unit/ml] * fasting
glucose [micro mol/l]/22.5).[8]
[Downloaded free from http://www.ijpvmjournal.net on Friday, July 20, 2018, IP: 176.120.110.104]
Khosravi, et al.: Vitamin D supplementation, weight loss, glycemic indices, and lipid prole
International Journal of Preventive Medicine 2018, 9: 63 3
Statistical analysis
Normal distributions of all variables were analyzed by the
Kolmogorov–Smirnov test and by evaluating the histogram
curves. All variables had normal distribution. Analyses
were performed with independent t‑test and paired t‑test.
The data were analyzed with SPSS version 20 (IBM,
Armonk, NY, USA). The signicance was considered 0.05.
Independent t‑test and Chi‑square was used  to comparison
the general characteristics of participants.
Results
From 75 potentially eligible participants, 6 persons were
excluded due to the personal reasons, 8 persons had
normal serum levels of vit D, and 5 blood specimens
were devastated due to the laboratory personnel mistake.
We could not take blood from 3 participants because
of high weight. Hence, they were eliminated. Finally,
we had 53 individuals that 26 of them were assigned
to intervention group and 27 of them were entered into
control group. The baseline characteristics of 53 obese and
overweight women are shown in Table 1. Anthropometric
variables of participants are presented in Table 2.
According to data, there were no signicantly differences
in baseline anthropometric variables between intervention
and control groups except WC which was signicantly
higher (P = 0.04) in intervention group. The analysis showed
that in intervention group, the means of weight, BMI, and
WC were reduced signicantly (73.2 ± 7.6–71.6 ± 7.7,
28 ± 2.7–27.2 ± 2.8, 90.4 ± 7.2–88 ± 7.5, respectively)
(P < 0.001), but WHR (0.85 ± 0.05–0.84 ± 0.06) did
not change signicantly [Table 2]. As it has shown in
Table 3, there were no differences in means of dietary
energy, macronutrient, and micronutrient such as vit D of
participants between two groups. Biochemical variables
were reported in Table 4. The assessment of biochemical
markers (HDL‑c, LDL‑c, TC, TG, FBS, Ins, HOMA‑IR) in
two groups shown that there were no signicant differences
in all of the biochemical variables (P > 0.05), except for
the vit D that was 21.9 ± 6.5 in intervention and 18.1 ± 4.8
in control groups (P < 0.01). The mean of differences in
anthropometric and laboratory variables were presented
in Table 5. After calculating the mean of differences in
two groups, it was cleared that intervention with the vit
D (P < 0.001) decreased the means of weight (1.6 ± 1.3),
BMI (0.6 ± 0.5), and WC (2.3 ± 1.1) and increased
the mean of vit D (62 ± 29, P < 0.001). Furthermore,
after adjusting for age, the means of the vit D was
signicant (83.49 ± 5.43, 34.2 ± 5.33 P = 0.001).
Discussion
The ndings of this double‑blind clinical trial study in obese
and overweight women aged 20–40 years showed that
supplementation of the vit D with dozes 50,000 IU/w for
6 weeks reduced signicantly the mean of BMI, weight, WC,
and on the other hand, it increased signicantly the level of
vit D in comparison with the control group. However, there
were no signicant effect of the vit D on other factors such
Table 1: Baseline characteristics of the participants
Parameter Intervention
(n=260)
Control
(n=27)
P*
Age 29.1±9.6 26.9±9.1 0.4
The number of children 1.0±1.3 0.48±0.93 0.06
Job (%)
Homeworker 30.80 25.90 0.54
Student 53.80 66.70
Employee 15.40 7.4
Marital status (%)
Single 53.80 33.3 0.13
Married 46.20 66.70
Education level (%)
Less than high school 3.8 11.10 0.24
High school and higher 46.2 18.50
College education and higher 50.00 70.40
Physical activity (min/week) 874.8±697.1 604.5±643.4 0.14
Sun exposure (min/day) 49.6±40 61.5±49.3 0.34
*P<0.05 is signicant; obtained from independent t‑test and
χ2, Values are mean±SD. SD=Standard deviation
Table 2: Anthropometric variables of the participants
Variables Intervention
(n=26)
Control
(n=27)
P*,‡
Weight (kg)
Baseline 73.2±7.6 70.3±9 0.02
End 71.6±7.7 70.3±9
P*0.001 0.81
Height 162±7 158.8±6 0.8
BMI (kg/m²)
Baseline 28±2.7 27.8±2.6 0.91
End 27.2±2.8 27.8±2.7 0.4
P*0.001 0.81
WC (cm)
Baseline 90.4±7.2 86±8 0.04
End 88±7.5 86.3±8.5 0.42
P*0.001 0.27
WHR
Baseline 0.85±0.05 0.81±0.05 0.4
End 0.84±0.06 0.82±0.06 0.4
P*0.23 0.44
SBP (mmHg)
Baseline 112.7±8.5 112.5±5 0.9
End 112.3±10 112±6.5 0.8
P*0.8 0.6
DBP (mmHg)
Baseline 80±6.5 78.5±8.5 0.4
End 78±5 76±6 0.2
P*0.15 0.17
*P<0.05 is signicant, Values are mean±SD, For comparison of
between‑group differences by an independent t‑test. BMI=Body
mass index, WC=Waist circumference, WHR=Waist to hip ratio,
SBP=Systolic blood pressure, DBP=Diastolic blood pressure,
SD=Standard deviation
[Downloaded free from http://www.ijpvmjournal.net on Friday, July 20, 2018, IP: 176.120.110.104]
Khosravi, et al.: Vitamin D supplementation, weight loss, glycemic indices, and lipid prole
International Journal of Preventive Medicine 2018, 9: 634
as hip circumference (HC), WHR, SBP, diastolic BP (DBP),
lipid proles, glycemic indexes, and CRP. Supplemental
interventions on women aged 20–40 years were our study
target because they were as mothers and had an important
role in prevalence of chronic diseases and therefore health
of society. The result of this study demonstrated that
supplementation of the vit D in obese and overweight
women reduced signicantly the mean of weight, BMI, and
WC. Previous studies had shown that the vit D deciency
is more prevalent in obese people and there was an inverse
association between vit D, BMI, and WC.[3,4,9,11,13‑21] Vashi
et al. showed that 1 kg/m² increase in BMI was associated
with signicantly reduced vit D level (42% ng/ml).[22] In
another study, there was a signicant inverse relationship
after adjusting all confounding that associated with vit
D and BMI.[23] However, conicting results have been
seen[3,17,24] such as a study on Iranian 20–64 years with BMI
24.2 ± 3.8 (57% female) which had not shown signicant
association between the level of vit D and BMI. Probably,
its main reason was BMI, which was 24.2 and in the normal
range. In addition, it could be another reason that only 48%
of individuals had vit D deciency.[17] In some studies,
the inverse association between vit D and WC has been
seen.[22,25] In one of these studies, vit D also had a signicant
association with HC.[25] In Seo’s study only, this association
between vit D and WC has been seen in women.[14]
Our study did not have a signicant effect on FBS, ins, and
HOMA‑IR. A study in 2012 has not found any signicant
effect on FBS and HOMA‑IR with supplementation of
vit D with dozes 1000 IU/d during 1 year.[26] In another
study, there was no signicant relationship between vit
D and HOMA‑IR because of participants were healthy
overweight adults with normal FBS.[3] From this aspect, it
was similar to our study. Furthermore, in several studies,
vit D did not have a relationship with fasting ins, IR,
and fasting glucose.[20,27‑30] Of course in some studies, vit
D had an inverse effect on HOMA‑IR, fasting ins, and
FBS.[16,18] We could not nd any signicant effect of vit
D; this effect may be seen in long‑term studies. In this
study, we could not nd any role of vit D on the lipid
prole such as TG, TC, HDL‑c, and LDL‑c. Result of
this study were approved by previous studies.[31‑33] In
Moghassemi and Marjani’s study of Iran, after 12 weeks
supplementation with the vit D, lipid prole did not
change signicantly.[31] Also, in a randomly clinical trial
on women has not found any changes in lipid prole that
it maybe related to short duration of study and dose
of the vit D.[23] In addition, some studies such as Women
Health Initiative that had longer duration and dose of the
vit D was 200 IU that take it twice a week for 7 years
has not found changes in lipid prole.[33] In several
Table 3: Dietary intake of participants before study
Nutrient Intervention
(n=26)
Control
(n=27)
P*,‡
Energy (kcal) 2096±6.3 2117±661 0.9
Carbohydrate (g) 292±107 300±157 0.8
Protein (g) 83±36 102.5±89 0.5
Fat (g) 73.5±31 78.5±77 0.3
Saturated fatty acid (g) 20±8 24.5±23 0.4
Polyunsaturated fatty acid (g) 21.5±12 22±15 0.8
Monounsaturated fatty acid (g) 32.2±118 42±214 0.7
Fiber soluble (g) 0.5±0.2 0.8±1.5 0.3
Fiber insoluble (g) 4.5±8 6±12.5 0.5
Calcium (mg) 841±363 899±646 0.7
Vitamin D (Ug) 1.4±1.9 1.3±2 0.93
*P<0.05 is signicant, Values are mean±SD, For comparison of
between‑group differences by an independent t‑test. SD=Standard
deviation
Table 4: Biochemical variables in participants
Variable Intervention
(n=26)
Control
(n=27)
P*,‡
HDL‑C (mg/dl)
Baseline 42.8±11.5 48.7±16 0.1
End 42.8±8.7 44.3±10 0.5
P0.1 0.7
LDL‑C (mg/dl)
Baseline 89.5±25 91.4±27 0.8
End 92.7±25.5 87.5±21.2 0.4
P0.3 0.3
TC (mg/dl)
Baseline 184.3±37 188.7±42.5 0.7
End 184±34 176.5±28 0.4
P0.9 0.07
FBS (mg/dl)
Baseline 96.8±12 101±13 0.2
End 90.5±9.5 91.2±12 0.8
P0.01 0.003
TG (mg/dl)
Baseline 118±90 109.5±56 0.7
End 120.5±111 100±48 0.4
P0.8 0.1
Vitamin D (nmol/l)
Baseline 22±6.5 18±5 0.01
End 84±30.5 34±24 0.001
P0.001 0.001
Insulin (mg/dl)
Baseline 10.2±6 9.5±5 0.6
End 13±8 10±6 0.1
P0.09 0.5
HOMA‑IR (mU/l)
Baseline 2.4±1.5 2.4±1.1 0.84
End 2.9±1.9 2.2±1.5 0.16
P0.25 0.7
*P<0.05 is signicant, Values are mean±SD, For comparison
of between‑group differences by an independent t‑test for
comparison of within‑group differences by an paired t‑test.
TC=Total cholesterol, TG=Triglyceride, LDL‑C=Low‑density
lipoprotein cholesterol, HDL‑C=High‑density lipoprotein
cholesterol, FBS=Fasting blood sugar, SD=Standard deviation,
HOMA‑IR=Homeostasis model assessment of insulin resistance
[Downloaded free from http://www.ijpvmjournal.net on Friday, July 20, 2018, IP: 176.120.110.104]
Khosravi, et al.: Vitamin D supplementation, weight loss, glycemic indices, and lipid prole
International Journal of Preventive Medicine 2018, 9: 63 5
studies, similar results were obtained.[20,22,26] However,
some studies have found inverse results such as Kim
et al. that after supplementation of the vit D only, HDL‑c
was reduced signicantly.[30] in another study LDL‑c
and TG decreased signicantly[34] but HDL‑c increased
signicantly.[35] In a similar study, after consuming the
supplementation of vit D with dozes 300 IU/d for 3 years,
LDL‑c and TG increased signicantly but TC and HDL‑c
reduced signicantly[36] A meta‑analysis was conducted
on the effects of vit D supplementation on lipid prole.
showed that only LDL was changed signicantly after the
intervention.[25] Overall, there are contradictory results
for the effect of the vit D on lipid proles, so more
investigations are necessary in the future. We have not
seen a signicant relationship between supplementation of
the vit D and BP in our study. A clinical study in Germany
supplementation of the vit D with dozes 100,000 IU did
not cause any changes in BP.[37] In a meta‑analysis that
included 10 interventional studies, after supplementation
of the vit D, no signicant effects was found in systolic
and DBP.[38] As well as several other studies have not
reported the effect of vit D on BP.[26,39,40] Of course, a
study has reported an inverse relationship between vit D
levels and systolic BP in men,[19] but probably, its main
reason was individuals’ age because the aim society in this
study were the individuals with age higher than 65 years
and mostly had a high BP but participants in our study
were individuals with age 20–40 years that mostly had a
normal BP. Another possible reason was the difference in
gender.
We could not nd any effect of the vit D on CRP in our
study. In a study on the healthy population, vit D had no
effect on CRP.[26] Forooghi et al. in Iran have not found
effect of vit D on CRP too.[41] Furthermore, another
studies had similar results. In some studies, an inverse
association has been seen between vit D and CRP. It means
that supplementation of the vit D can reduce CRP.[42,43] In
an interventional study on obese people, CRP increased
signicantly.[16] According to the previous studies, the
reason of the vit D deciency in obesity has not cleared yet
but some mechanisms has proposed these reasons for the
relationship between vit D and obesity: trapped of the vit D
in adipose tissue that makes less bioavailability for convert
to the form of 1,25(OH)2D.[10] In a study vit D deciency
was accompanied with abdominal obesity. Therefore, vit
D is lower in serum of obese people, and therefore, its
bioavailability reduces for these individuals.[16] The role
of vit D in causing IR has not cleared yet. Some studies
have suggested that vit D may have benecial effects
on ins responsiveness by stimulating expression of ins
receptors[44] or regulating calcium homeostasis which
is necessary for intracellular ins‑mediated processes.[45]
As regard to the obesity is the most common cause of
ins‑resistance, the relation between vit D and IR might
be the result of increased body size.[16] We could not nd
the effect of vit D on lipid proles, glycemic indexes,
CRP, and BP in this study. Some studies have reported
these effects which were mostly due to the weight loss
and BMI reduction that improved these factors. The
possible effect of vit D on BP may be related to regulation
the renin–angiotensin system, suppression the spread of
proliferation of vascular smooth muscle cells, improvement
IR, modication extended‑dependent cells to endothelium
and inhibition of anticoagulant activity and hypertrophy of
myocardial cells.[46] Possibility mechanism for the effect
of vit D in CRP reduction is that vit D receptors are in
more than 37 body tissues that effect on these organs by
their receptors and regulate pro‑inammatory mechanisms
and systematic inammation in the body. Vit D receptors
are located in the nucleus of macrophages. Some of these
macrophages produce cytokines, especially Tumor necrosis
factor (TNF)‑α. TNF‑α expression signicantly depends
on the effect of NF‑β. Increased vit D inhibits the protein
expression of NF‑β and reduces the expression of NF‑β and
thus reduces the level of TNF‑α. In addition, vit D binds
to receptors on monocytes and so produce in ammatory
cytokines, CRP and reduces systemic in ammation.[41]
We performed this study as an interventional that gave us
a more acceptable result. We included women aged 20–
40 years that were at risk for vit D de ciency had more
exposure to disease in the future.
Limitations
The short duration of the study and increase in the levels
of the vit D in control group were our limitation. One of
Table 5: The mean of differences in anthropometric and
biochemical variables
Variable Intervention
(n=26)
Control
(n=27)
P*,‡
Weight (kg) −1.6±1.3 0.05±1 0.001
BMI −0.61±0.5 0.02±0.5 0.001
WC (cm) −2.3±1 0.3±1.5 0.001
WHR 0.01±0.04 −0.0008±0.03 0.22
HDL‑C (mg/dl) 0.003±8 −4.4±12.5 0.13
LDL‑C (mg/dl) 3.17±17.5 −4±19 0.17
TC (mg/dl) −0.3±26 −12.2±33.5 0.15
FBS (mg/dl) −6.35±12 −9.5±15.5 0.4
TG (mg/dl) 2.5±48.5 −9±34.5 0.3
Vitamin D 62±29 15.7±22 0.001
Insulin (mg/dl) 3±8 0.66±6 0.27
HOMA‑IR (mU/l) 0.5±2.1 −0.11±1.5 0.23
SBP (mmHg) −0.5±8 −0.75±7 0.9
DBP (mmHg) −2.3±8 −2.6±9.6 0.9
*P<0.05 is signicant, Values are mean±SD, For comparison
of between‑group differences by an independent t‑test. TC=Total
cholesterol, TG=Triglyceride, LDL‑C=Low‑density lipoprotein
cholesterol, HDL‑C=High‑density lipoprotein cholesterol,
FBS=Fasting blood sugar, SBP=Systolic blood pressure,
DBP=Diastolic blood pressure, HOMA‑IR=Homeostasis
model assessment of insulin resistance, BMI=Body mass index,
WC=Waist circumference, WHR=Waist to hip ratio
[Downloaded free from http://www.ijpvmjournal.net on Friday, July 20, 2018, IP: 176.120.110.104]
Khosravi, et al.: Vitamin D supplementation, weight loss, glycemic indices, and lipid prole
International Journal of Preventive Medicine 2018, 9: 636
the possible causes of this increase can be attributed to
the seasons. With the arrival of summer, the amount and
intensity of the sun increases, and spontaneously, levels
of vit D increases. Entrance healthy obese individuals
with normal laboratory indexes may be the reason for not
signicant effects. The authors declared that there is no
conict of interest.
Conclusions
Overall supplementation of the vit D with dozes
50,000 IU/w for 6 weeks in obese and overweight women
aged 20–40 years reduced in the mean of BMI, weight,
and WC signicantly and vit D increased signicantly
compared to the control group.
Financial support and sponsorship
Nil.
Conicts of interest
There are no conicts of interest.
Received: 13 Oct 15 Accepted: 15 Dec 17
Published: 20 Jul 18
References
1. Holick MF, Chen TC. Vitamin D deciency: A worldwide
problem with health consequences. Am J Clin Nutr
2008;87:1080S‑6S.
2. Javidan AN, Sabour H, Lati S, Vafa M, Shidfar F,
Khazaeipour Z, et al. Calcium and Vitamin D plasma
concentration and nutritional intake status in patients with
chronic spinal cord injury: A referral center report. J Res Med
Sci 2014;19:881‑4.
3. Kim M, Na W, Sohn C. Correlation between Vitamin D and
cardiovascular disease predictors in overweight and obese
koreans. J Clin Biochem Nutr 2013;52:167‑71.
4. Forsythe LK, Livingstone MB, Barnes MS, Horigan G,
McSorley EM, Bonham MP, et al. Effect of adiposity on
Vitamin D status and the 25‑hydroxycholecalciferol response to
supplementation in healthy young and older irish adults. Br J
Nutr 2012;107:126‑34.
5. Barja‑Fernandez S, Leis R, Casanueva FF, Seoane LM. Drug
development strategies for the treatment of obesity: How to
ensure efcacy, safety, and sustainable weight loss. Drug Des
Devel Ther 2014;8:2391‑400.
6. Peirson L, Douketis J, Ciliska D, Fitzpatrick‑Lewis D, Ali MU,
Raina P, et al. Prevention of overweight and obesity in adult
populations: A systematic review. CMAJ Open 2014;2:E268‑72.
7. Joharapurkar AA, Dhanesha NA, Jain MR. Inhibition of the
methionine aminopeptidase 2 enzyme for the treatment of
obesity. Diabetes Metab Syndr Obes 2014;7:73‑84.
8. Peirson L, Douketis J, Ciliska D, Fitzpatrick‑Lewis D, Ali MU,
Raina P, et al. Treatment for overweight and obesity in adult
populations: A systematic review and meta‑analysis. CMAJ
Open 2014;2:E306‑17.
9. Sarrafzadegan N, Talaei M, Sadeghi M, Mohammadifard N,
Taheri M, Lotzadeh M, et al. Determinants of weight change in
a longitudinal study of iranian adults: Isfahan cohort study. Arch
Iran Med 2014;17:539‑44.
10. Grethen E, McClintock R, Gupta CE, Jones R, Cacucci BM,
Diaz D, et al. Vitamin D and hyperparathyroidism in obesity.
J Clin Endocrinol Metab 2011;96:1320‑6.
11. Veghari G, Sedaghat M, Maghsodlo S, Banihashem S,
Moharloei P, Angizeh A, et al. Differences in the prevalence
of obesity among fars‑native, turkman, and sisstanish ethnic
groups in Iranian Northern adults in 2010. Int Cardiovasc Res J
2013;7:56‑61.
12. Salehpour A, Hosseinpanah F, Shidfar F, Vafa M, Razaghi M,
Dehghani S, et al. A 12‑week double‑blind randomized clinical
trial of Vitamin D3 supplementation on body fat mass in healthy
overweight and obese women. Nutr J 2012;11:78.
13. Sadeghi M, Talaei M, Oveisgharan S, Rabiei K, Dianatkhah M,
Bahonar A, et al. The cumulative incidence of conventional risk
factors of cardiovascular disease and their population attributable
risk in an Iranian population: The isfahan cohort study. Adv
Biomed Res 2014;3:242.
14. Rodríguez‑Rodríguez E, Navia B, López‑Sobaler AM,
Ortega RM. Vitamin D in overweight/obese women and
its relationship with dietetic and anthropometric variables.
Obesity (Silver Spring) 2009;17:778‑82.
15. Muscogiuri G, Sorice GP, Prioletta A, Policola C, Della Casa S,
Pontecorvi A, et al. 25‑hydroxyvitamin D concentration
correlates with insulin‑sensitivity and BMI in obesity.
Obesity (Silver Spring) 2010;18:1906‑10.
16. Moy FM, Bulgiba A. High prevalence of Vitamin D insufciency
and its association with obesity and metabolic syndrome among
malay adults in Kuala Lumpur, Malaysia. BMC Public Health
2011;11:735.
17. Baradaran A, Behradmanesh S, Nasri H. Association of body
mass index and serum Vitamin D level in healthy Iranian
adolescents. Endokrynol Pol 2012;63:29‑33.
18. Kang JH, Kim SS, Moon SS, Kim WJ, Bae MJ, Choi BG, et al.
Adiposity in the relationship between serum Vitamin D level and
insulin resistance in middle‑aged and elderly korean adults: The
Korea National Health and Nutrition Examination Survey 2008.
Endocrinol Metab (Seoul) 2013;28:96‑102.
19. Seo JA, Cho H, Eun CR, Yoo HJ, Kim SG, Choi KM, et al.
Association between visceral obesity and sarcopenia and Vitamin
D deciency in older Koreans: The ansan geriatric study. J Am
Geriatr Soc 2012;60:700‑6.
20. Vilarrasa N, Vendrell J, Maravall J, Elío I, Solano E, San José P,
et al. Is plasma 25(OH) D related to adipokines, inammatory
cytokines and insulin resistance in both a healthy and morbidly
obese population? Endocrine 2010;38:235‑42.
21. Johnson LK, Hofsø D, Aasheim ET, Tanbo T, Holven KB,
Andersen LF, et al. Impact of gender on Vitamin D deciency in
morbidly obese patients: A cross‑sectional study. Eur J Clin Nutr
2012;66:83‑90.
22. Vashi PG, Lammersfeld CA, Braun DP, Gupta D. Serum
25‑hydroxyvitamin D is inversely associated with body mass
index in cancer. Nutr J 2011;10:51.
23. Snijder MB, van Dam RM, Visser M, Deeg DJ, Dekker JM,
Bouter LM, et al. Adiposity in relation to Vitamin D status and
parathyroid hormone levels: A population‑based study in older
men and women. J Clin Endocrinol Metab 2005;90:4119‑23.
24. Scragg R, Holdaway I, Singh V, Metcalf P, Baker J, Dryson E,
et al. Serum 25‑hydroxyvitamin D3 is related to physical activity
and ethnicity but not obesity in a multicultural workforce. Aust
N Z J Med 1995;25:218‑23.
25. Wang H, Xia N, Yang Y, Peng DQ. Inuence of Vitamin D
supplementation on plasma lipid proles: A meta‑analysis of
randomized controlled trials. Lipids Health Dis 2012;11:42.
26. Breslavsky A, Frand J, Matas Z, Boaz M, Barnea Z,
Shargorodsky M, et al. Effect of high doses of Vitamin D on
[Downloaded free from http://www.ijpvmjournal.net on Friday, July 20, 2018, IP: 176.120.110.104]
Khosravi, et al.: Vitamin D supplementation, weight loss, glycemic indices, and lipid prole
International Journal of Preventive Medicine 2018, 9: 63 7
arterial properties, adiponectin, leptin and glucose homeostasis in
type 2 diabetic patients. Clin Nutr 2013;32:970‑5.
27. Mathieu C, Gysemans C, Giulietti A, Bouillon R. Vitamin D and
diabetes. Diabetologia 2005;48:1247‑57.
28. Beilfuss J, Berg V, Sneve M, Jorde R, Kamycheva E. Effects of
a 1‑year supplementation with cholecalciferol on interleukin‑6,
tumor necrosis factor‑alpha and insulin resistance in overweight
and obese subjects. Cytokine 2012;60:870‑4.
29. Reis JP, von Mühlen D, Miller ER 3rd. Relation of
25‑hydroxyvitamin D and parathyroid hormone levels with
metabolic syndrome among US adults. Eur J Endocrinol
2008;159:41‑8.
30. Kim HJ, Kang CK, Park H, Lee MG. Effects of Vitamin D
supplementation and circuit training on indices of obesity
and insulin resistance in T2D and Vitamin D decient elderly
women. J Exerc Nutrition Biochem 2014;18:249‑57.
31. Moghassemi S, Marjani A. The effect of short‑term Vitamin
D supplementation on lipid prole and blood pressure in
post‑menopausal women: A randomized controlled trial. Iran J
Nurs Midwifery Res 2014;19:517‑21.
32. Wood AD, Secombes KR, Thies F, Aucott L, Black AJ,
Mavroeidi A, et al. Vitamin D3 supplementation has no effect
on conventional cardiovascular risk factors: A parallel‑group,
double‑blind, placebo‑controlled RCT. J Clin Endocrinol Metab
2012;97:3557‑68.
33. Hsia J, Heiss G, Ren H, Allison M, Dolan NC, Greenland P,
et al. Calcium/Vitamin D supplementation and cardiovascular
events. Circulation 2007;115:846‑54.
34. Zittermann A, Frisch S, Berthold HK, Götting C, Kuhn J,
Kleesiek K, et al. Vitamin D supplementation enhances the
benecial effects of weight loss on cardiovascular disease risk
markers. Am J Clin Nutr 2009;89:1321‑7.
35. Naharci I, Bozoglu E, Kocak N, Doganci S, Doruk H, Serdar M,
et al. Effect of Vitamin D on insulin sensitivity in elderly
patients with impaired fasting glucose. Geriatr Gerontol Int
2012;12:454‑60.
36. Heikkinen AM, Tuppurainen MT, Niskanen L, Komulainen M,
Penttilä I, Saarikoski S, et al. Long‑term Vitamin
D3 supplementation may have adverse effects on serum lipids
during postmenopausal hormone replacement therapy. Eur J
Endocrinol 1997;137:495‑502.
37. Schleithoff SS, Zittermann A, Tenderich G, Berthold HK,
Stehle P, Koerfer R, et al. Vitamin D supplementation improves
cytokine proles in patients with congestive heart failure:
A double‑blind, randomized, placebo‑controlled trial. Am J Clin
Nutr 2006;83:754‑9.
38. Ke L, Mason RS, Kariuki M, Mpofu E, Brock KE. Vitamin D
status and hypertension: A review. Integr Blood Press Control
2015;8:13‑35.
39. Seiki S, Chonchol M, Cheung AK, Kaufman JS, Greene T,
Roberts WL, et al. 25‑hydroxyvitamin D deciency is
associated with an increased risk of metabolic syndrome in
patients with non‑diabetic chronic kidney disease. Clin Nephrol
2012;78:432‑41.
40. Zittermann A, Schleithoff SS, Tenderich G, Berthold HK,
Körfer R, Stehle P, et al. Low Vitamin D status: A contributing
factor in the pathogenesis of congestive heart failure? J Am Coll
Cardiol 2003;41:105‑12.
41. Foroughi M, Maghsoudi Z, Ghiasvand R, Iraj B, Askari G.
Effect of Vitamin D supplementation on C‑reactive protein
in patients with nonalcoholic fatty liver. Int J Prev Med
2014;5:969‑75.
42. Jorde R, Sneve M, Torjesen PA, Figenschau Y, Gøransson LG,
Omdal R, et al. No effect of supplementation with cholecalciferol
on cytokines and markers of inammation in overweight and
obese subjects. Cytokine 2010;50:175‑80.
43. Gholami K, Talasaz AH, Entezari‑Maleki T, Salarifar M,
Hadjibabaie M, Javadi MR, et al. The effect of high‑dose
Vitamin D3 on soluble P‑selectin and hs‑CRP level in patients
with venous thromboembolism: A Randomized clinical trial. Clin
Appl Thromb Hemost 2016;22:483‑9.
44. Maestro B, Campión J, Dávila N, Calle C. Stimulation by
1,25‑dihydroxyvitamin D3 of insulin receptor expression and
insulin responsiveness for glucose transport in U‑937 human
promonocytic cells. Endocr J 2000;47:383‑91.
45. Wright DC, Hucker KA, Holloszy JO, Han DH. Ca2+ and
AMPK both mediate stimulation of glucose transport by muscle
contractions. Diabetes 2004;53:330‑5.
46. Pittas AG, Chung M, Trikalinos T, Mitri J, Brendel M, Patel K,
et al. Systematic review: Vitamin D and cardiometabolic
outcomes. Ann Intern Med 2010;152:307‑14.
[Downloaded free from http://www.ijpvmjournal.net on Friday, July 20, 2018, IP: 176.120.110.104]
... Moreover, obesity-related hypovitaminosis D could be attributed to the decreased bioavailability of the fat soluble vitamin D in the circulation of obese individuals due to the greater storage of vitamin D in fat tissues (15,17,18). Contrariwise, studies suggest that vitamin D may regulate body composition (19,20), while a recent meta-analysis indicates that vitamin D supplementation in overweight and obese individuals may serve as a possible therapeutic option for weight l oss interventions (21) (PTH) concentration which subsequently stimulates calcium influx into adipocytes and thereby promotes adipogenesis. Another hypothesis that supports the involvement of vitamin D deficiency in the pathophysiology of obesity is that 1,25(OH) 2 D and VDR are implicated in adipocyte differentiation (19,22). ...
... The results of the current study are in agreement with the study of Salehpour et al. which indicates that 12 weeks supplementation with vitamin D 3 1000 IU/d without a weight loss program in healthy overweight and obese women (n = 77) with mean serum 25(OH)D level 16.4 ± 12.56 ng/ml (41.8 ± 31.4 nmol/L), significantly decreased body fat mass (19). Similarly, Khosravi et al. found a significant reduction in weight, BMI and waist and hip circumference, while vitamin D level was improved in 50 overweight and obese women aged 20-40, in a 6-week 50000 IU/week vitamin D supplementation, following their usual diet (20). In addition, Lotfi-Dizaji et al. concluded that a 12 week 50,000 IU/week vitamin D supplementation along with calorie restriction diet in44 obese volunteers with vitamin D deficiency (25(OH)D < 20ng/ml) diminished significantly weight and fat mass and improved serum 25(OH)D level (28). ...
Article
Full-text available
Vitamin D deficiency or insufficiency is common in obese people, with some studies suggesting that low vitamin D level might be an independent predictor of obesity. Thus, the purpose of the present randomized, double-blind, placebo-controlled study was to investigate the effect of oral spray vitamin D 3 3000 IU supplementation along with personalized weight-loss diet on obesity markers in overweight and obese Caucasians with vitamin d deficiency or insufficiency. The impact of vitamin D receptor (VDR) and adrenergic receptors (ADRs) genetic variants on vitamin D levels and weight loss diet outcomes was also investigated. After signing informed consent, a total of 125 eligible volunteers were randomly assigned into vitamin D (vitamin D 3 3000 IU/d oral spray supplementation, n = 76) or placebo (xylitol, water, mint, n = 49) group following a weight loss program (600 calories less than the total energy expenditure of each volunteer) for 3 months. Fat mass, BMI, REE and 25(OH)D serum level were monitored on baseline and each month. DNA samples were extracted from buccal swabs and genotyped for the rs2228570 (VDR), rs1544410 (VDR), rs731236 (VDR), rs1800544 (ADRA2A), rs1801252 (ADRB1), rs1042713 (ADRB2), and rs4994 (ADRB3) polymorphisms. Statistical analysis was performed using SPSS package (v.23). Between group comparisons revealed significant improvement in serum 25(OH)D level and greater reduction in weight, BMI and fat percentage in the vitamin D group compared to placebo group (p < 0.05). In the vitamin D group, carriers of the rs2228570 T allele tended to have greater vitamin D level improvement compared with the homozygous C allele (p = 0.067). Furthermore, heterozygous (CT) for the rs731236 tended to have lesser weight loss (p = 0.068) and for the rs1042713, a lower decline in fat percentage was observed for homozygous AA carriers compared to the heterozygous (p = 0.051). Xenos et al. Vitamin D Supplementation and Weight Loss In the control group, differences in weight loss (p = 0.055) and BMI (p = 0.045) were observed between rs1544410 AA and GG homozygous. In conclusion, vitamin D oral spray supplementation seems to improve vitamin D status and decrease obesity markers during a weight-loss intervention in overweight/obese Caucasians with vitamin D deficiency or insufficiency. Also, the results of the present study indicate that VDR and ADRs genetic polymorphisms seem to influence vitamin D supplementation response and obesity markers.
... Jääskeläinen et al. showed the low 25(OH)D as a predictor of increasing waist circumference among men in a 11-years follow-up study (Jääskeläinen et al., 2020). Also, Khosravi et al. demonstrated that 25(OH)D supplementation with 50000 IU per week, for six weeks reduced weight, BMI and waist circumference in obese and overweight females (Khosravi et al., 2018). In addition, waist circumference of participants who consumed yogurt, either of intervention or control groups, was lower after the duration of study (p < 0.001). ...
Article
Purpose The purpose of the current study was to evaluate the effects of nano-encapsulated 25(OH)D fortified (1500 IU Nano-encapsulated 25(OH)D dairy products on anti-heat shock protein 27 antibody (anti-Hsp27) titers, pro-oxidant-antioxidant balance (PAB) and cytokines concentration in adults with abdominal obesity. Materials and methods This study was part of SUVINA project and designed as a randomized trial. Middle aged adults (n = 306) recruited among students and staff of Mashhad University of Medical Sciences [Iran]. Subjects were randomly assorted into four groups: a low-fat yogurt fortified with 1500 IU 25(OH)D (n = 76), and unfortified yogurt (n = 77), a low-fat milk fortified with 1500 IU 25(OH)D (n = 76), and unfortified milk (n = 77) were followed up for 10 weeks. A total of 289 subjects completed the study. Body mass index (BMI) and waist circumference were measured before and after the ten weeks of intervention. The following biochemical markers were determined: serum pro-oxidant-antioxidant balance (PAB), 25(OH)D, anti-Hsp27 titers and cytokines concentration, at baseline and at the end of the study. Result There was a significant difference between serum 25(OH)D concentration and PAB at baseline and the end of intervention with fortified milk and yogurt. After the intervention period, changes between groups of intervention group of both of the milk and yogurt and control group were statistically significant for serum 25(OH)D concentration (p < 0.001) and PAB (p < 0.05). In the group provide with fortified milk, waist circumference was decreased (−2.01 ± 3.85 cm, p < 0.05) and serum 25(OH)D concentration increased significantly (5.02 ± 4.07 ng/ml, p < 0.001). In the group taking the fortified yogurt, serum 25(OH)D status increased by 6.75 ± 3.42 ng/ml (p < 0.001) and PAB decreased by −21.85 ± 48.07 HK (p < 0.05). Our results did not show any significant differences in mean weight between the groups (p > 0.05). Conclusion Our results showed that after the intervention with 25(OH)D fortified yogurt or milk in obese subjects, serum PAB concentrations decreased and serum 25(OH)D increased significantly. Therefore, fortification of low-fat yogurt and milk with 25(OH)D may be effective in reducing the pro-oxidant anti-oxidant balance with effect thsat are greater than for unfortified dairy products.
... Obesity constitutes one of the major risk factors for non-communicable metabolic diseases. [1] Metabolic disorders like diabetes, insulin resistance, and cardiovascular disease are not a simple dysfunction of the local organs, instead they are uncoordinated among hormones productions in different organs. [2] Adipose tissue and liver are the highly active endocrine organs that secrete bioactive molecules which are highly contributive in regulating body energy metabolism and cardiovascular tone. ...
Article
Context: Obesity is associated with endothelial dysfunction and cardiovascular diseases. Adiponectin and fibroblast growth factor 21 (FGF21) as hormones are highly contributive in cardiovascular system, while they are disrupted through obesity. Weight-bearing high intensity interval training (HIIT) as an effective procedure in preventing obesity-related complications in adults with obesity may be limited due to the subjects' muscular weakness and complications interfering walking. Aims: The purpose of this study was to assess the effectiveness of non-weight bearing all extremity HIIT (all ex. HIIT) on FGF21, adiponectin, nitric oxide (NO), and flow mediated dilation (FMD) in overweight and obese women. Methods: Thirty healthy overweight and obese sedentary university female students within 20.53 ± 1.50 age range and BMI ≥27 kg.m-2 were assigned in two experimental and control groups. All ex. HIIT consisted of 4 × 4 min at 85-90% max HR with an interspersed with 3 × 3 min recovery per round at 70% max HR by upper and lower ergometers in a simultaneous manner on 10 weeks of four sessions of 40 min each. FGF21, adiponectin, NO, FMD, weight, waist and maximal oxygen uptake (VO2max) were measured in pre and post-tests. Paired sample t-test and analysis of covariance are applied for statistical analysis. Results: Results indicated a significant increase in adiponectin (P ≤ 0.01) and FMD (P ≤ 0.001), while there existed no changes in FGF21 at (P ≥ 0.10) and NO (P ≥ 0.84). The weight and waist decreased at (P ≤ 0.001), and the VO2max increased at (P ≤ 0.001). Conclusions: All ex. HIIT may be a safe alternative for overweigh and obese women who have complications with weight-bearing exercises, and may increase adiponectin, and improve the FMD, aerobic fitness, and body composition.
... High secretion of this hormone is related to insulin resistance. Some randomized controlled trials showed a decreased leptin level [118] and a reduced BMI [119] after high doses of vitamin D administration to insulin-resistant patients. ...
Article
Full-text available
The study was conducted to comprehensively assess the association of the concentration of vitamin D in the blood and insulin resistance in non-diabetic subjects. The objective was to pool the results from all observational studies from the beginning of 1980 to August 2021. PubMed, Medline and Embase were systematically searched for the observational studies. Filters were used for more focused results. A total of 2248 articles were found after raw search which were narrowed down to 32 articles by the systematic selection of related articles. Homeostatic Model Assessment of Insulin Resistance (HOMAIR) was used as the measure of insulin resistance and correlation coefficient was used as a measure of the relationship between vitamin D levels and the insulin resistance. Risk of bias tables and summary plots were built using Revman software version 5.3 while Comprehensive meta-analysis version 3 was used for the construction of forest plot. The results showed an inverse association between the status of vitamin D and insulin resistance (r = −0.217; 95% CI = −0.161 to −0.272; p = 0.000). A supplement of vitamin D can help reduce the risk of insulin resistance; however further studies, like randomized controlled trials are needed to confirm the results.
... Despite several mechanisms attributed to Ca intake including the formation of insoluble calcium-fatty acid soaps in the gut and reduction of fatty acid absorption, [26,29] the short study duration and inclusion of normal lipemic participants may have contributed to weaker effects in our study as comparison with other surveys. [25,26] A nonsignificant effect of Vit D supplementation on the blood lipid profile was observed have been reported by others, which are in accordance with our findings [4,30,31] Heikkinen et al. suggested that Vit D supplementation may have unfavorable effects on lipids in postmenopausal women including an increase in serum LDL cholesterol; [32] however, other observational studies have revealed that after 8 weeks of intervention, the present study showed that a 500 kcal energy-restricted diet for 8 weeks reduces serum lipid levels in all groups which many of these alterations were statistically significant especially in the Ca and Ca + Vit D groups. These results may have potentially important public health implications and should be addressed by future clinical trials with longer duration especially among obese and hyperlipidemic individuals. ...
Article
Background: Dyslipidemia is often associated with obesity and contributes to the increased risk of atherosclerosis, heart disease, and stroke. This study was designed to evaluate the independent or combined effect of calcium and vitamin D (Ca + Vit D) supplementation on blood lipid profile in overweight or obese premenopausal women. Methods: This study is a triple-blind, randomized, parallel, placebo-controlled trial. About 100 overweight or obese (body mass index (BMI) of 25-40 kg/m2) premenopausal (aged 30-50 years) women, recruited from Shiraz University of Medical Sciences (SUMS) clinics, were allocated into 4 groups: (1) calcium (Ca) supplementation (2 tablets per day; each containing 500 mg calcium carbonate), (2) vitamin D (Vit D) supplementation (2 tablets per day; each containing 200 IU vitamin D3), (3) Ca + Vit D supplementation (2 tablets per day; each containing 500 mg calcium carbonate plus 200 IU vitamin D3), (4) placebo supplementation (2 tablets per day, containing micro-cellulose). All participants received a 500 kcal energy-restricted diet. Blood lipids, serum vitamin D, and anthropometric indices were measured at baseline and after 8 weeks. Physical activity and 3-day dietary records were taken at baseline and every 4 weeks during the intervention. Results: At 8 weeks, triglyceride levels were significantly decreased in the Ca group (P = 0.002). Low-density lipoprotein (LDL) levels were decreased in the Ca + Vit D group (P = 0.04) and high-density lipoprotein (HDL) levels decreased in both the Ca and Ca + Vit D groups (P = 0.006, P = 0.004, respectively). The results of one-way ANOVA indicated that changes in the serum lipid profile levels were not significantly different among the four groups (P = 0.90, P = 0.86, P = 0.61, P = 0.27, and P = 0.19, respectively for TG, TC, LDL, HDL, and LDL/HDL). The results were not significant even after adjusting for potential covariates. Conclusions: Although the results were not significantly different among the four treated groups at 8 weeks, within-group changes like the reduction in triglyceride and LDL levels, respectively in the Ca group and Ca + Vit D group, and HDL levels in both the Ca and Ca + Vit D groups were significant. These changes may have potentially significant public health implications.
... Moreover, it has been previously observed that vitamin D by itself may be related to lower HDL concentrations [40]. Nevertheless, other studies have reported no relationship between vitamin D and lipid profiles [39,41,42]. Nevertheless, we should bear in mind that adiposity is recognized to greatly impact metabolic parameters and lipids. ...
Article
Full-text available
(1) Background: Observational studies have established that vitamin D-binding protein (DBP) and 25-hydroxyvitamin D3 (25(OH)D) concentrations are the major factors affecting the bioavailability of 25(OH)D. It has also been shown that poor 25(OH)D bioavailability elevates the risk of obesity and its related cardio-metabolic disorders. However, the relationship between 25(OH)D and DBP concentrations with cardio-metabolic risk factors in overweight and obese cohorts has not been established. Consequently, we evaluated the association between DBP and 25(OH)D concentrations with lipid profile, blood pressure (BP), and body composition in overweight and obese women. (2) Methods: In this cross-sectional study of 236 overweight and obese women, DBP and 25(OH)D concentrations were measured using an enzyme-linked immunosorbent assay. Body composition was assessed via bioelectrical impedance analysis. Lipid profile and BP were assessed by an auto-analyzer and digital BP monitor, respectively. The associations were examined by multivariate logistic regression. (3) Results: The indicated showed an inverse relationship between DBP and high-density lipoprotein (HDL) (p = 0.010) concentrations (where individuals with higher DBP had lower HDL) which, after adjusting for possible cofounders, remained significant (p = 0.006). Moreover, DBP concentration was positively associated with fat mass index (FMI) after adjustment (p = 0.022). No significant relationships were observed among 25(OH)D and target variables. (4) Conclusions: In conclusion, lower concentrations of HDL and higher values of FMI are associated with higher concentrations of DBP in overweight and obese women. These findings present novel awareness regarding the association of DBP with some metabolic and body composition variables in overweight and obese women. However, a two-way causal relationship between DBP and target variables should be considered
Article
Full-text available
Research background. Oral microbiota has become an important factor in obesity, but its association with obesity-related diseases and serum 25-hydroxy vitamin D [25(OH)D] and B complex levels is still uncertain. The main aim of the paper was to determine variation in oral microbiota composition regarding vitamin status and obesity-related diseases in obese females from Croatia. We hypothesized that the prevalence of probiotic or pathogen bacteria in the oral cavity of obese women in Croatia depends on vitamin B9 (folic acid), B12, and 25(OH)D serum levels and/or hypertension, diabetes, and prediabetes diagnosis. Experimental approach. To test the defined research hypothesis, female individuals with body mass index (BMI) ?30 kg/m2 (N=70) were recruited to participate in this study. Obese women were divided into groups according to BMI value, diagnosis of obesity-related diseases, and micronutrients blood levels. For the quantitative determination of folic acid, vitamin B12, and 25(OH)D serum levels, an electrochemiluminescence protein binding assay (ECLIA) was performed. Isolated microorganisms from the saliva of obese women were analyzed by MALDI-TOF mass spectrometer. Results and conclusions. The present results do not support the hypothesis that the prevalence of probiotic or pathogen bacteria in the oral cavity of obese women in Croatia depends on the level of micronutrients in obese women from Croatia. On the other hand, hypertension and diabetes/prediabetes diagnosis favor the growth of oral pathogens, specifically increased levels of Candida sp. Novelty and scientific contribution. To the best of our knowledge, this is the first study showing the relationship between obesity, micronutrient level, oral microbiota composition, and the incidence of obesity-related disease. We included only obese women from Croatia, so it is regionally specific. Also, we have shown that oral microbiota composition is not connected with micronutrient deficiencies but only with obesity-related diseases.
Article
Full-text available
Adipose tissue plays an important role in systemic metabolism via the secretion of adipocytokines and storing and releasing energy. In obesity, adipose tissue becomes dysfunctional and characterized by hypertrophied adipocytes, increased inflammation, hypoxia, and decreased angiogenesis. Although adipose tissue is one of the major stores of vitamin D, its deficiency is detective in obese subjects. In the presented review, we show how vitamin D regulates numerous processes in adipose tissue and how their dysregulation leads to metabolic disorders. The molecular response to vitamin D in adipose tissue affects not only energy metabolism and adipokine and anti-inflammatory cytokine production via the regulation of gene expression but also genes participating in antioxidant defense, adipocytes differentiation, and apoptosis. Thus, its deficiency disturbs adipocytokines secretion, metabolism, lipid storage, adipogenesis, thermogenesis, the regulation of inflammation, and oxidative stress balance. Restoring the proper functionality of adipose tissue in overweight or obese subjects is of particular importance in order to reduce the risk of developing obesity-related complications, such as cardiovascular diseases and diabetes. Taking into account the results of experimental studies, it seemed that vitamin D may be a remedy for adipose tissue dysfunction, but the results of the clinical trials are not consistent, as some of them show improvement and others no effect of this vitamin on metabolic and insulin resistance parameters. Therefore, further studies are required to evaluate the beneficial effects of vitamin D, especially in overweight and obese subjects, due to the presence of a volumetric dilution of this vitamin among them.
Article
Full-text available
Adipose tissue plays an important role in systemic metabolism via the secretion of adipocytokines and storing and releasing energy. In obesity, adipose tissue becomes dysfunctional and characterized by hypertrophied adipocytes, increased inflammation, hypoxia, and decreased angiogenesis. Although adipose tissue is one of the major stores of vitamin D, its deficiency is detective in obese subjects. In the presented review, we show how vitamin D regulates numerous processes in adipose tissue and how their dysregulation leads to metabolic disorders. The molecular response to vitamin D in adipose tissue affects not only energy metabolism and adipokine and anti-inflammatory cytokine production via the regulation of gene expression but also genes participating in antioxidant defense, adipocytes differentiation, and apoptosis. Thus, its deficiency disturbs adipocytokines secretion, metabolism, lipid storage, adipogenesis, thermogenesis, the regulation of inflammation, and oxidative stress balance. Restoring the proper functionality of adipose tissue in overweight or obese subjects is of particular importance in order to reduce the risk of developing obesity-related complications, such as cardiovascular diseases and diabetes. Taking into account the results of experimental studies, it seemed that vitamin D may be a remedy for adipose tissue dysfunction, but the results of the clinical trials are not consistent, as some of them show improvement and others no effect of this vitamin on metabolic and insulin resistance parameters. Therefore, further studies are required to evaluate the beneficial effects of vitamin D, especially in overweight and obese subjects, due to the presence of a volumetric dilution of this vitamin among them.
Article
Full-text available
Introduction: Vitamin D Deficiency (VDD) and several other metabolic factors are known to be involved in the aggravation of Osteoarthritis (OA). A better understanding of the role of these metabolic factors and diseases is required to alleviate the OA progression. Aim: To analyse the prevalence of VDD in OA patients and its correlation with co-morbidities such as diabetes, hypertension (HT), Cardiovascular Disease (CVD) and acidity and also to assess the effect of Body Mass Index (BMI) and increasing age on the developmental process of OA. Materials and Methods: A cross-sectional survey was undertaken during September 2018 to March 2019 in King Khaled, King Salman and Hail General Hospitals located in Ha’il province of Kingdom of Saudi Arabia (KSA). The study included 501 participants of OA patients that visited these hospitals. Data pertaining to the variables in this study such as diabetes, HT, cardiovascular problems, vitamin D and calcium deficiency, acidity and anthropometric details was obtained using a structured questionnaire. Data analysis was done using descriptive statistics and Pearson’s correlation with the statistical program SPSS version 21. Results: VDD, calcium deficiency and acidity were the most prevalent factors observed in the patients. Vitamin D and calcium deficiency was observed to be higher in females than males. VDD significantly correlated to diabetes, HT, acidity and age, both in females and males. Cardiovascular disease and BMI correlated with VDD only in males but not in females. BMI showed positive correlation with HT in males (p<0.01) but not females, and also correlated with age (p<0.01) irrespective of gender. Conclusion: The study concluded that VDD is more prevalent in females than males in Ha’il region. It is correlated to variables such as diabetes, HT, acidity, BMI and increasing age, which are identified as risk factors contributing to the progression of OA.
Article
Full-text available
Abstract: Vitamin D is a steroid prohormone synthesized in the skin following ultraviolet exposure and also achieved through supplemental or dietary intake. While there is strong evidence for its role in maintaining bone and muscle health, there has been recent debate regarding the role of vitamin D deficiency in hypertension based on conflicting epidemiological evidence. Thus, we conducted a scoping systematic literature review and meta-analysis of all observational studies published up to early 2014 in order to map trends in the evidence of this association. Mixed-effect meta-analysis was performed to pool risk estimates from ten prospective studies (n=58,262) (pooled risk for incident hypertension, relative risk [RR] =0.76 (0.63–0.90) for top vs bottom category of 25-hydroxyvitamin D [25OHD]) and from 19 cross-sectional studies (n=90,535) (odds ratio [OR] =0.79 (0.73–0.87)). Findings suggest that the better the assessed quality of the respective study design, the stronger the relationship between higher 25OHD levels and hypertension risk (RR =0.67 (0.51–0.88); OR =0.77 (0.72–0.89)). There was significant heterogeneity among the findings for both prospective and cross-sectional studies, but no evidence of publication bias was shown. There was no increased risk of hypertension when the participants were of older age or when they were vitamin D deficient. Younger females showed strong associations between high 25OHD levels and hypertension risk, especially in prospective studies (RR =0.36 (0.18–0.72); OR =0.62 (0.44–0.87)). Despite the accumulating evidence of a consistent link between vitamin D and blood pressure, these data are observational, so questions still remain in relation to the causality of this relationship. Further studies either combining existing raw data from available cohort studies or conducting further Mendelian analyses are needed to determine whether this represents a causal association. Large randomized controlled trials are also needed to determine whether vitamin supplementation may be beneficial in the prevention or the treatment of hypertension. Keywords: 25OHD, high blood pressure, meta-analysis, prospective, cross-sectional, blood pressure
Article
Full-text available
The purpose of this study was to investigate the effects of vitamin D supplementation and circuit training on body composition, abdominal fat, blood lipids, and insulin resistance in T2D and vitamin D deficient elderly women. Fifty-two elderly women were randomly assigned to either the vitamin D supplementation with circuit training group (D+T: n = 15), the circuit training group (T: n = 13), the vitamin D supplementation group (D: n = 11), or the control group (CON: n = 13). The subjects in D took vitamin D supplements at 1,200 IU per day for 12 weeks; the subjects in T exercised 3 to 4 times per week, 25 to 40 minutes per session for 12 weeks; and the subjects in D+T participated in both treatments. Subjects in CON were asked to maintain normal daily life pattern for the duration of the study. Body composition, abdominal fat, blood lipids, and surrogate indices for insulin resistance were measured at pre- and post-test and the data were compared among the four groups and between two tests by utilizing two-way ANOVA with repeated measures. The main results of the present study were as follows: 1) Body weight, fat mass, percent body fat, and BMI decreased significantly in T, whereas there were no significant changes in the variables in D and CON. Lean body mass showed no significant changes in all groups. 2) TFA and SFA decreased significantly in T, whereas there were no significant changes in the variables in D and CON. The other abdominal fat related variables showed no significant changes in all groups. 3) TC, TG, HDL-C, and LDL-C showed improvements in T, whereas there were no significant changes in the variables in D and CON. 4) Fasting glucose, fasting insulin, and HOMA-IR tended to be lower in D+T. It was concluded that the 12 weeks of vitamin D supplementation and circuit training would have positive effects on abdominal fat and blood lipid profiles in T2D and vitamin D deficient elderly women. Vitamin D supplementation was especially effective when it was complemented with exercise training.
Article
Full-text available
Nutritional status influences bone health spinal cord injury (SCI). This study evaluates serum levels of 25-hydroxy-vitamin-D and calcium along with dietary intakes in patients with chronic SCI. Total of 160 patients participated in this investigation. Dietary intakes were assessed by semi-quantitative food-frequency questionnaire. Serum calcium, phosphorus and 25(OH)-vitamin-D level were measured. Mean of serum calcium and 25(OH)-vitamin-D were 9.54 ± 0.64 mg/dl (standard error of the mean [SE]: 0.05) and 13.6 ± 10.99 μg/dl (SE: 0.9), respectively. Dairy intake was below recommended amount (1.8 ± 0.74 per serving (SE: 0.06), recommended: 4). A high prevalence (53.1%) of Vitamin D deficiency (25(OH) Vitamin D <13 ng/ml) was found. This study shows below adequate intake of calcium and Vitamin D in Iranian patients with SCI. These results insist on the importance of dietary modifications among these patients.
Article
Full-text available
Cardiovascular diseases (CVDs) are the leading cause of death in Iran. The present study evaluated the 7-year incidence of CVD risk factors among the participants of Isfahan cohort study (ICS). ICS was a longitudinal study on adults over 35 years of age from the urban and rural areas in three counties in central Iran. Data on clinical examination and blood measurements were collected in 2001. Subjects were followed and similar data were collected in 2007. Cumulative incidence was calculated through dividing new cases of each risk factor by the population free of that risk factor at baseline. Incidence proportion was determined for major CVD risk factors including hypertension (HTN), hypercholesterolemia (HC), hypertriglyceridemia (HTg), obesity, diabetes mellitus (DM), metabolic syndrome (MetS), and smoking. A total number of 6323 adults free of CVDs were recruited. After 7 years of follow-up, 3283 individuals were re-evaluated in 2007. The participants' age was 49.2 ± 10.3 years in 2001 (mean ± SD). The 7-year cumulative incidence of HTN, HC, HTg, overweight, obesity, DM, MetS, and smoking was 22.8%, 37.4%, 28.0%, 26.3%, 7.4%, 9.5%, 23.9%, and 5.9% in men and 22.2%, 55.4%, 33.5%, 35.0%, 18.8%, 11.3%, 36.1%, and 0.7% in women, respectively. Among those with overweight or obesity, 14.7% of men and 7.9% of women decreased their weight up to the normal level. The present study revealed a high incidence of CVD risk factors especially dyslipidemia, obesity, MetS and HTN. Therefore, the application of life-style modification interventions seems necessary.
Article
Full-text available
The prevalence of obesity has increased worldwide, and approximately 25%-35% of the adult population is obese in some countries. The excess of body fat is associated with adverse health consequences. Considering the limited efficacy of diet and exercise in the current obese population and the use of bariatric surgery only for morbid obesity, it appears that drug therapy is the only available method to address the problem on a large scale. Currently, pharmacological obesity treatment options are limited. However, new antiobesity drugs acting through central nervous system pathways or the peripheral adiposity signals and gastrointestinal tract are under clinical development. One of the most promising approaches is the use of peptides that influence the peripheral satiety signals and brain-gut axis such as GLP-1 analogs. However, considering that any antiobesity drug may affect one or several of the systems that control food intake and energy expenditure, it is unlikely that a single pharmacological agent will be effective as a striking obesity treatment. Thus, future strategies to treat obesity will need to be directed at sustainable weight loss to ensure maximal safety. This strategy will probably require the coadministration of medications that act through different mechanisms.
Article
Full-text available
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the worldwide. It is associated with chronic disorders such as diabetes and heart diseases. Inflammation is one of the basic causes of metabolic diseases. Several studies have shown that Vitamin D can reduce inflammation. The purpose of this study was to investigate the effect of Vitamin D supplementation on inflammation in patients with NAFLD. This study involved 60 NAFLD patients, divided equally into two intervention and placebo groups. During 10 weeks, patients in the intervention group receive Vitamin D (capsules containing 50,000 IU vitamin D), weekly. Vitamin D levels, C-reactive protein (CRP), triglyceride (TG), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were measured at the beginning and end of the study. Data were analyzed using analysis of covariance tests. Analyses were done using SPSS software (version 16) (SPSS Inc., Chicago, USA). P < 0.05 set as significant level. Vitamin D supplementation resulted in an increase of serum 25(OH) D concentrations in inter group (P < 0.05) and intra-group (P < 0.05) in intervention group. At the end of the study, in the intervention group, TG and CRP reduced significantly compare with baseline (P < 0.05). A significant increase was seen in calcium serum in the intervention group in comparison with baseline (P < 0.05) and compared with the placebo group (P < 0.05). Vitamin D supplementation had no effect on CRP and other variables in the intervention group compared with the placebo group. Further studies with strong design and more sample must conduct to demonstrate the effect of Vitamin D supplementation on inflammation in patients with NAFLD.
Article
Full-text available
Obesity is a major public health issue. This review updates the evidence on the effectiveness of behavioural and pharmacologic treatments for overweight and obesity in adults. We updated the search conducted in a previous review. Randomized trials of primary-care-relevant behavioural (diet, exercise and lifestyle) and pharmacologic (orlistat and metformin) with or without behavioural treatments in overweight and obese adults were included if 12-month, postbaseline data were provided for weight outcomes. Studies reporting harms were included regardless of design. Data were extracted and pooled wherever possible for 5 weight outcomes, 6 secondary health outcomes and 4 adverse events categories. We identified 68 studies, most consisted of short-term (≤ 12 mo) treatments using diet (n = 8), exercise (n = 4), diet and exercise (n = 10), lifestyle (n = 19), orlistat (n = 25) or metformin (n = 4). Compared with the control groups, intervention participants had a greater weight loss of -3.02 kg (95% confidence interval [CI] -3.52 to -2.52), a greater reduction in waist circumference of -2.78 cm (95% CI -3.34 to -2.22) and a greater reduction in body mass index of -1.11 kg/m(2) (95% CI -1.39 to -0.84). The relative risk for loss of ≥ 5% body weight was 1.77 (95% CI 1.58-1.99, [number needed to treat 5, 95% CI 4-7]), and the relative risk for loss of ≥ 10% body weight was 1.91 (95% CI 1.69-2.16, [number needed to treat 9, 95% CI 7-12]). Incidence of type 2 diabetes was lower among pre-diabetic intervention participants (relative risk 0.62 [95% CI 0.50-0.77], number needed to treat 17 [95% CI 13-29]). With prevalence rates for type 2 diabetes on the rise, weight loss coupled with a reduction in the incidence of type 2 diabetes could potentially have a significant benefit on population health and a possible reduction in need for drug treatments for glycemic control. There is moderate quality evidence that behavioural and pharmacologic plus behvioural, treatments for overweight and obesity in adults lead to clinically important reductions in weight and incidence of type 2 diabetes in pre-diabetic populations. Registration: PROSPERO no. CRD42012002753.
Article
Full-text available
The prevalence of normal-weight adults is decreasing, and the proportion in excessive weight categories (body mass index ≥ 25) is increasing. In this review, we sought to identify interventions to prevent weight gain in normal-weight adults. We searched multiple databases from January 1980 to June 2013. We included randomized trials of primary care-relevant behavioural, complementary or alternative interventions for preventing weight gain in normal-weight adults that reported weight change at least 12 months after baseline. We included any studies reporting harms. We planned to extract and pool data for 4 weight outcomes, 6 secondary health outcomes and 5 adverse events categories. One small study provided moderate-quality evidence. The 12-month program, which used education and financial strategies and was offered more than 25 years ago in the United States, was successful in stabilizing weight and producing weight loss. More intervention participants maintained their baseline weight or lost weight than controls (82% v. 56%, p < 0.0001), and program participants maintained their weight better than controls by showing greater weight reduction by the end of the intervention (mean difference adjusted for height -0.82, 95% confidence interval -1.57 to -0.06, kg). No evidence was available for sustained effects or for any other weight outcomes, secondary outcomes or harms. We were unable to determine whether behavioural interventions led to weight-gain prevention and improved health outcomes in normal-weight adults. Given the importance of primary prevention, and the difficulty of losing weight and maintaining weight loss, this paucity of evidence is surprising and leaves clinicians and public health practitioners with unclear direction. Registration: PROSPERO no. CRD42012002753.
Article
Vitamin D deficiency is now recognized as a pandemic. The major cause of vitamin D deficiency is the lack of appreciation that sun exposure in moderation is the major source of vitamin D for most humans. Very few foods naturally contain vitamin D, and foods that are fortified with vitamin D are often inadequate to satisfy either a child's or an adult's vitamin D requirement. Vitamin D deficiency causes rickets in children and will precipitate and exacerbate osteopenia, osteoporosis, and fractures in adults. Vitamin D deficiency has been associated with increased risk of common cancers, autoimmune diseases, hypertension, and infectious diseases. A circulating level of 25-hydroxyvitamin D of >75 nmol/L, or 30 ng/mL, is required to maximize vitamin D's beneficial effects for health. In the absence of adequate sun exposure, at least 800–1000 IU vitamin D3/d may be needed to achieve this in children and adults. Vitamin D2 may be equally effective for maintaining circulating concentrations of 25-hydroxyvitamin D when given in physiologic concentrations.
Article
High plasma level of P-selectin is associated with the development of venous thromboembolism (VTE). Furthermore, supplementation of vitamin D could decrease thrombotic events. Hence, this study was designed to examine whether the administration of vitamin D can influence the plasma level of P-selectin in patients with VTE. In the randomized controlled trial, 60 patients with confirmed acute deep vein thrombosis and/or pulmonary embolism (PE) were randomized into the intervention (n = 20) and control (n = 40) groups. The intervention arm was given an intramuscular single dose of 300 000 IU vitamin D3. Plasma level of 25-hydroxy vitamin D, P-selectin, and high-sensitive C-reactive protein (hs-CRP) was measured at baseline and 4 weeks after. The plasma level of P-selectin (95% confidence interval = -5.99 to -1.63, P = .022) and hs-CRP (P = .024) significantly declined in vitamin D-treated group, while only hs-CRP was significantly decreased in the control group (P = .011). However, the magnitude of these reductions was not statistically significant. This study could not support the potential benefit of the high-dose vitamin D on plasma level of P-selectin and hs-CRP in patients with VTE. © The Author(s) 2015.