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ABSTRACT: Weight gain after diagnosis is common among women with breast cancer, yet results have been inconsistent among the few studies examining its effects on survival.
We examined the effects of weight gain on mortality among a cohort of 1436 women diagnosed with a first primary breast cancer in 1996-1997, on Long Island, NY. Subjects were interviewed soon after diagnosis and again after approximately 5 years. Weight was assessed at each decade of adult life; 1 year before, at, and 1 year after diagnosis; and at the time of follow-up. Mortality through the end of 2005 was assessed using the National Death Index. Proportional hazards regression was used while using a selection model to account for missing data.
Compared with women who maintained their prediagnosis weight (±5%), those who gained more than 10% after diagnosis had worse survival (hazard ratio [HR] = 2.67; [95% credible interval = 1.37-5.05]). The effect was more pronounced during the first 2 years after diagnosis (>5% gain: all-cause mortality in the first 2 years, HR = 5.87 [0.89-47.8] vs. after 2 years, 1.49 [0.85-2.57]); among women overweight before diagnosis (overweight women: all-cause HR = 1.91 [0.91-3.88] vs. ideal-weight women, 1.39 [0.62-3.01]); and for women who had gained at least 3 kg in adulthood before diagnosis (≥3-kg gain before diagnosis: 1.80 [0.99-3.26 vs. <3 kg gain before diagnosis: 1.07 [0.30-3.37].
These results highlight the importance of weight maintenance for women after breast cancer diagnosis.
Epidemiology (Cambridge, Mass.) 03/2012; 23(2):320-7. · 5.51 Impact Factor
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Jessie A Satia
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ABSTRACT: This article provides an overview of the phenomena of "dietary acculturation" and the "nutrition transition". The term dietary acculturation is defined, and a proposed model for how dietary acculturation occurs is presented. Various approaches to assessing dietary acculturation in research studies are discussed, and a research-driven discussion of the possible consequences of dietary acculturation on diet and health is presented. The concept of the nutrition transition and the importance of understanding this phenomenon are presented. Specifically, the term nutrition transition is defined, highlighting characteristic dietary changes, as well as shifts in physical activity and obesity trends. The paradox of continued high rates of malnutrition in developing countries and a new emergence of dietary excess, sedentary behavior, obesity, and other chronic diseases in middle- and upper-class persons in these countries will also be addressed. The article concludes with suggestions for future research in the areas of dietary acculturation and the nutrition transition.
Applied Physiology Nutrition and Metabolism 04/2010; 35(2):219-23. · 2.13 Impact Factor
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ABSTRACT: To investigate the relationship between antioxidant nutrients (vitamins C and E, beta-carotene, selenium) and DNA methylation-related nutrients (folate, vitamins B6 and B12) and distal colorectal cancer risk in whites and African Americans and to examine intakes from food only versus total (food plus dietary supplements) intakes.
Data are from the North Carolina Colon Cancer Study-Phase II, a case-control study of 945 distal colorectal cancer (including sigmoid, rectosigmoid, and rectum) cases and 959 controls. In-person interviews captured usual dietary intake and various covariates. Multivariate logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI).
High intakes of each antioxidant and DNA methylation-related nutrient were significantly associated with lower risk in whites. In African Americans, the highest category of selenium from food only had a marginally significant inverse association with distal colorectal cancer risk (Q4 vs. Q1 OR: 0.55, 95% CI 0.29-1.02). Supplements did not provide additional risk reduction beyond intakes from food.
Our findings provide evidence that antioxidant and DNA methylation-related nutrients may lower the risk of distal colorectal cancer in whites, and selenium may lower risk in African Americans. Optimal micronutrient intakes from food alone may be more beneficial than supplementation.
Cancer Causes and Control 03/2010; 21(8):1171-81. · 2.88 Impact Factor
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ABSTRACT: There is a dearth of knowledge regarding factors that may motivate African American adolescents to consume healthier diets.
To develop and test cancer prevention messages based on Prospect Theory on motivation to improve dietary intake in African American adolescents and to explore other salient factors that may inform dietary intervention design and implementation in this population.
Semistructured in-person qualitative interviews were conducted with 13 African American male and female adolescents, aged 12 to 16 years, in North Carolina. Prospect Theory and message framing were used to guide the design of the 4 sets of diet-related messages related to cancer prevention: short-term, gain-framed; long-term, gain-framed; short-term, loss-framed; and long-term, loss-framed messages. Data were also collected on demographic, behavioral, and psychological factors; usual health behaviors; and preferences for intervention delivery.
Most respondents found the gain-framed, short-term messages most salient for both fruits/vegetables (8 [61.5%]) and fat consumption (7 [53.8%]). For fat consumption only, 2 (15.4%) found the loss-framed, short-term messages pertinent; none found the loss-framed, long-term messages relevant for either dietary variable. All indicated interest in participating in a dietary intervention/education program; most preferred the Internet as a channel for intervention delivery. Participants expressed diverse views regarding knowledge, attitudes, and beliefs regarding healthy eating.
The gain-framed, short-term messages were most salient for motivating the majority of respondents to consume a healthy diet and most expressed a strong interest in participating in programs about diet and nutrition, with the Internet as the preferred communication channel.
Researchers conducting dietary interventions and education initiatives and medical professionals who counsel African American adolescents should consider using Prospect Theory as a theoretical framework, should focus on gain-framed, short-term messages regarding cancer prevention, and should use the Internet for data collection and intervention and information delivery.
Cancer nursing 02/2010; 33(2):102-9. · 1.88 Impact Factor
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ABSTRACT: Lung cancer is the leading cause of cancer-related mortality among women. The role of hormone replacement therapy (HRT) in lung cancer development is unclear.
We evaluated a prospective cohort of 36,588 peri- and postmenopausal women aged 50 to 76 years from Washington State recruited in 2000 to 2002 (Vitamins and Lifestyle [VITAL] Study). Lung cancer cases (n = 344) were identified through the Seattle-Puget Sound Surveillance, Epidemiology, and End Results cancer registry during 6 years of follow-up. Hazard ratios (HRs) associated with use and duration of specific HRT formulations were calculated for total incident lung cancer, specific morphologies, and cancer by stage at diagnosis.
After adjusting for smoking, age, and other potential confounders, there was an increased risk of incident lung cancer associated with increasing duration of estrogen plus progestin (E+P) use (HR = 1.27 for E+P use 1 to 9 years, 95% CI, 0.91 to 1.78; and HR = 1.48 for E+P use > or = 10 years, 95% CI, 1.03 to 2.12; P for trend = .03). There was no association with duration of unopposed estrogen use. Duration of E+P use was associated with an advanced stage at diagnosis (P for trend = .03).
Use of E+P increased the risk of incident lung cancer in a duration-dependent manner, with an approximate 50% increased risk for use of 10 years or longer. These findings may be helpful for informing women of their risk of developing lung cancer and delineating important pathways involved in hormone metabolism and lung cancer.
Journal of Clinical Oncology 02/2010; 28(9):1540-6. · 18.37 Impact Factor
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ABSTRACT: Studies have suggested that red and processed meat consumption elevate the risk of colon cancer; however, the relationship between red meat, as well as fat and protein, and distal colorectal cancer (CRC) specifically is not clear. We determined the risk of distal CRC associated with red and processed meat, fat, and protein intakes in Whites and African Americans. There were 945 cases (720 White, 225 African American) of distal CRC and 959 controls (800 White, 159 African American). We assessed dietary intake in the previous 12 mo. Multivariate logistic regression analyses were used to obtain odds ratios (OR) and 95% confidence intervals (95% CI). There was no association between total, saturated, or monounsaturated fat and distal CRC risk. In African Americans, the OR of distal CRC for the highest category of polyunsaturated fat intake was 0.28 (95% CI = 0.08-0.96). The percent of energy from protein was associated with a 47% risk reduction in Whites (Q4 OR = 0.53, 95% CI = 0.37-0.77). Red meat consumption in Whites was associated with a marginally significant risk reduction (Q4 OR = 0.66, 95% CI = 0.43-1.00). Our results do not support the hypotheses that fat, protein, and red meat increase the risk of distal CRC.
Nutrition and Cancer 01/2010; 62(6):701-9. · 2.78 Impact Factor
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ABSTRACT: Oxidative stress is a potentially important aetiological factor for many chronic diseases, including cardiovascular disease, neurodegenerative disease and cancer, yet studies often find inconsistent results. The associations between three of the most widely used biomarkers of oxidative stress, i.e. F(2)-isoprostanes for lipid peroxidation and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) and the comet assay with FPG for oxidative DNA damage, were compared in a sample of 135 healthy African-American and white adults. Modest associations were observed between F(2)-isoprostanes and the comet assay (r = 0.22, p = 0.01), but there were no significant correlations between 8-oxo-dG and the comet assay (r = -0.09) or F(2)-IsoP (r = -0.04). These results are informative for researchers seeking to compare results pertaining to oxidative stress across studies and/or assessment methods in healthy disease-free populations. The development and use of oxidative stress biomarkers is a promising field; however, additional validation studies are necessary to establish accuracy and comparability across oxidative stress biomarkers.
Biomarkers 12/2009; 14(8):587-95. · 2.21 Impact Factor
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ABSTRACT: Millions of Americans use dietary supplements with little knowledge about their benefits or risks. We examined associations of various herbal/specialty supplements with lung and colorectal cancer risk. Men and women, 50 to 76 years, in the VITamins And Lifestyle cohort completed a 24-page baseline questionnaire that captured duration (years) and frequency (days per week) of use of commonly used herbal/specialty supplements. Dose was not assessed due to the lack of accurate potency information. Supplement exposure was categorized as "no use" or "any use" over the previous 10 years. Hazard ratios (HR) were estimated by multivariate Cox regression models. Incident lung (n = 665) and colorectal cancers (n = 428) were obtained from the Surveillance, Epidemiology, and End Results cancer registry. Any use of glucosamine and chondroitin, which have anti-inflammatory properties, over the previous 10 years, was associated with significantly lower lung cancer risk: HR 0.74 [95% confidence interval (95% CI), 0.58-0.94] and HR 0.72 (95% CI, 0.54-0.96) and colorectal cancer risk: HR 0.73 (95% CI, 0.54-0.98) and HR 0.65 (95% CI, 0.45-0.93), respectively. There were also statistically significantly inverse associations of fish oil: HR 0.65 (95% CI, 0.42-0.99), methylsulfonylmethane: HR 0.46 (95% CI, 0.23-0.93), and St. John's wort: HR 0.35 (95% CI, 0.14-0.85) with colorectal cancer risk. In contrast, garlic pills were associated with a statistically significant 35% elevated colorectal cancer risk. These results suggest that some herbal/specialty supplements may be associated with lung and colorectal cancer risk; however, these products should be used with caution. Additional studies examining the effects of herbal/specialty supplements on risk for cancer and other diseases are needed.
Cancer Epidemiology Biomarkers & Prevention 06/2009; 18(5):1419-28. · 4.12 Impact Factor
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ABSTRACT: Associations between individual foods and nutrients and colorectal cancer have been inconsistent, and few studies have examined associations between food, nutrients, dietary patterns, and rectal cancer. We examined the relationship between food groups and dietary patterns and risk for rectal cancer in non-Hispanic Whites and African-Americans.
Data were from the North Carolina Colon Cancer Study-Phase II and included 1,520 Whites (720 cases, 800 controls) and 384 African-Americans (225 cases, 159 controls). Diet was assessed using the Diet History Questionnaire. Multivariate logistic regression models were used to estimate odds ratios and 95% confidence intervals.
Among Whites, non-whole grains and white potatoes were associated with elevated risk for rectal cancer whereas fruit, vegetables, dairy, fish, and poultry were associated with reduced risk. In African-Americans, high consumption of other fruit and added sugar suggested elevated risk. We identified three major dietary patterns in Whites and African-Americans. The high fat/meat/potatoes pattern was observed in both race groups but was only positively associated with risk in Whites (odds ratio, 1.84; 95% confidence interval, 1.03-3.15). The vegetable/fish/poultry and fruit/whole grain/dairy patterns in Whites had significant inverse associations with risk. In African-Americans, there was a positive dose-response for the fruit/vegetables pattern (P(trend) < 0.0001) and an inverse linear trend for the legumes/dairy pattern (P(trend) < 0.0001).
Our findings indicate that associations of certain food groups and overall dietary patterns with rectal cancer risk differ between Whites and African-Americans, highlighting the importance of examining diet and cancer relationships in racially diverse populations.
Cancer Epidemiology Biomarkers & Prevention 05/2009; 18(5):1552-61. · 4.12 Impact Factor
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Jessie A Satia
Journal of the American Dietetic Association 05/2009; 109(4):610-5. · 3.59 Impact Factor
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ABSTRACT: Lung cancer is the most common cause of cancer-related mortality. Smoking cessation is crucial to decrease risk, but additional prevention modalities are needed. The use of nonsteroidal anti-inflammatory drugs (NSAID) may be promising.
The study was a prospective cohort of 77,125 men and women, ages 50 to 76 years, from Washington state recruited in 2000 to 2002 (the VITamin And Lifestyle study). Lung cancer cases were identified through the Seattle-Puget Sound Surveillance, Epidemiology and End Results cancer registry during 5 years of follow-up. Hazard ratios (HR) associated with 10-year average use of total NSAIDs (excluding low-dose aspirin) and specific categories of NSAIDs were calculated for total incident lung cancer and specific morphologies.
A total of 665 lung cancer cases were identified. After adjusting for smoking, age, gender, and acetaminophen use, there was a borderline-significant inverse trend with total NSAID use [>4.2 d/wk for >10 years versus none: HR, 0.82; 95% confidence interval (95% CI), 0.64-1.04; P for trend = 0.05]. The association was strongest for adenocarcinoma (HR, 0.59; 95% CI, 0.37-0.94; P for trend = 0.01) and seemed to be limited to men (HR, 0.66; 95% CI, 0.47-0.92; P for trend = 0.01) and to long-term (> or =10 years) former smokers (HR, 0.65; 95% CI, 0.44-0.96; P for trend = 0.04). There were no appreciable differences by NSAID type.
Total NSAID use was associated with a small reduced risk of lung cancer, which was strongest for adenocarcinoma, men, and long-term former smokers. These findings are supported by known lung carcinogenesis mechanisms and suggest that NSAIDS may be useful for chemoprevention.
Cancer Epidemiology Biomarkers & Prevention 04/2009; 18(4):1203-7. · 4.12 Impact Factor
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ABSTRACT: High antioxidant intakes are inversely related to risk for many diseases. However, there is no comprehensive instrument that captures consumption of antioxidant nutrients from both foods and dietary supplements. This report examines the validity of a newly developed questionnaire assessing self-reported dietary and supplemental intakes of antioxidant nutrients (carotenoids, vitamin C, and vitamin E). Between March and December 2005, participants (n=164), 20 to 45 years old, completed the new 92-item antioxidant nutrient questionnaire, a demographic/health questionnaire, four 24-hour dietary recalls, a dietary supplement inventory, and provided semi-fasting blood samples that were analyzed for plasma antioxidant levels. Data analyses included descriptive statistics, correlation coefficients, and linear regression. Mean age of participants was 31.9 years, 51% were African American, and 52% were female. Median antioxidant intakes from the questionnaire and mean of the four recalls were generally comparable. Adjusted Pearson's correlations of questionnaire- and recall-derived intakes ranged from r=0.06 to r=0.56; correlations for the questionnaire and biomarkers ranged from r=0.10 to r=0.33. Agreement rates for classification of intakes from the questionnaire and recalls into the same/adjacent quartiles were 65% to 89%; misclassification to the opposite quartile was rare (range=0 to 12%). For most nutrients, there were linear trends of increasing plasma concentrations with higher questionnaire-derived intakes (P<0.01). Correlations of supplement use between the questionnaire and a supplement inventory were r=0.33 to r=0.84. The new antioxidant nutrient questionnaire demonstrated good validity for collecting self-reported antioxidant nutrient intakes from foods and supplements in both whites and African Americans. The study also underscores the importance of examining the performance characteristics of dietary assessment instruments separately in different population subgroups.
Journal of the American Dietetic Association 03/2009; 109(3):502-8, 508.e1-6. · 3.59 Impact Factor
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ABSTRACT: High-dose beta-carotene supplementation in high-risk persons has been linked to increased lung cancer risk in clinical trials; whether effects are similar in the general population is unclear. The authors examined associations of supplemental beta-carotene, retinol, vitamin A, lutein, and lycopene with lung cancer risk among participants, aged 50-76 years, in the VITamins And Lifestyle (VITAL) cohort Study in Washington State. In 2000-2002, eligible persons (n = 77,126) completed a 24-page baseline questionnaire, including detailed questions about supplement use (duration, frequency, dose) during the previous 10 years from multivitamins and individual supplements/mixtures. Incident lung cancers (n = 521) through December 2005 were identified by linkage to the Surveillance, Epidemiology, and End Results cancer registry. Longer duration of use of individual beta-carotene, retinol, and lutein supplements (but not total 10-year average dose) was associated with statistically significantly elevated risk of total lung cancer and histologic cell types; for example, hazard ratio = 2.02, 95% confidence interval: 1.28, 3.17 for individual supplemental lutein with total lung cancer and hazard ratio = 3.22, 95% confidence interval: 1.29, 8.07 for individual beta-carotene with small-cell lung cancer for >4 years versus no use. There was little evidence for effect modification by gender or smoking status. Long-term use of individual beta-carotene, retinol, and lutein supplements should not be recommended for lung cancer prevention, particularly among smokers.
American journal of epidemiology 02/2009; 169(7):815-28. · 5.59 Impact Factor
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ABSTRACT: We examined associations of dietary patterns with colon cancer risk in African Americans and Whites from a case-control study in North Carolina. Incident colon cancer cases, 40 to 80 yr (n = 636), and matched controls (n = 1,042) were interviewed in person to elicit information on potential colon cancer risk factors. A validated food frequency questionnaire adapted to include regional foods captured diet over the year prior to diagnosis (cases) or interview date (controls). Three meaningful intake patterns were identified in both Whites and African Americans: "Western-Southern," "fruit-vegetable," and "metropolitan." Compared to the Western-Southern pattern, the fruit-vegetable and metropolitan patterns were associated with more healthful dietary behaviors (e.g., higher vegetable intake and lower red meat consumption), and demographic/lifestyle characteristics typically correlated with low colon cancer risk, for example, lower BMI, higher education, and higher NSAID use. The fruit-vegetable pattern was significantly inversely associated with colon cancer risk in Whites (OR = 0.4, 95% CI = 0.3-0.6) and the metropolitan pattern with a nonsignificant 30% risk reduction in both Whites and African Americans after adjustment for education. The Western-Southern pattern was not associated with colon cancer risk. These findings may explain some of the racial differences in colon cancer incidence and underscore the importance of examining diet-cancer associations in different population subgroups.
Nutrition and Cancer 02/2009; 61(2):179-93. · 2.78 Impact Factor
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ABSTRACT: Selenium is an essential trace element that has been implicated in cancer risk; however, study results have been inconsistent with regard to colon cancer. Our objectives were to 1) investigate the association between selenium and colon cancer, 2) evaluate possible effect measure modifiers, and 3) evaluate potential biases associated with the use of postdiagnostic serum selenium measures. The North Carolina Colon Cancer Study is a large population-based, case-control study of colon cancer in North Carolina between 1996 and 2000 (n = 1,691). Nurses interviewed patients about diet and lifestyle and drew blood specimens, which were used to measure serum selenium. Individuals who had both high serum selenium (> 140 mcg/l) and high reported folate (> 354 mcg/day) had a reduced relative risk of colon cancer [odds ratio (OR) = 0.5, 95% confidence interval (CI) = 0.4-0.8). The risk of colon cancer for those with high selenium and low folate was approximately equal to the risk among those with low selenium and low folate (OR = 1.1, 95% CI = 0.7-1.5) as was the risk for those with low selenium and high folate (OR = 0.9, 95% CI = 0.7-1.2). We did not find evidence of bias due to weight loss, stage at diagnosis, or time from diagnosis to selenium measurement. High levels of serum selenium and reported folate jointly were associated with a substantially reduced risk of colon cancer. Folate status should be taken into account when evaluating the relation between selenium and colon cancer in future studies. Importantly, weight loss, stage at diagnosis, or time from diagnosis to blood draw did not appear to produce strong bias in our study.
Nutrition and Cancer 02/2009; 61(2):165-78. · 2.78 Impact Factor
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ABSTRACT: Disparities in incidence and mortality rates of colon cancer exist between Whites and African Americans. Prior studies examined the association between trans fatty acid consumption and colorectal cancer, but none assessed this possible relationship within a large study population of African Americans and Whites. Using data from a population-based, case-control study in North Carolina, we investigated this association with attention to possible racial differences. Cases and matched controls were queried on demographic characteristics, lifestyle factors, medical history, and diet. Cases reported higher daily consumption (g/day) of trans fatty acids (mean = 5.9, SD = 2.9, median = 5.5, IQR = 3.8-7.5) compared to controls (mean = 5.2, SD = 2.4, median = 4.7, IQR = 3.5-6.4). Energy-adjusted trans fatty acid consumption was not associated with colon cancer. Compared to participants in the lowest quartile of consumption, those in the highest quartile had an adjusted odds ratio of 1.01 (95% confidence interval 0.69, 1.49) for Whites and 0.99 (95% confidence interval 0.61, 1.62) for African Americans. No association was found between increased consumption of trans fatty acid and specific tumor location (proximal or distal colon). In conclusion, trans fatty acid consumption is not associated with colon cancer and does not contribute to disparities in colon cancer rates.
Nutrition and Cancer 01/2009; 61(4):427-36. · 2.78 Impact Factor
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ABSTRACT: Despite the belief that the etiology of and risk factors for rectal cancer might differ from those for colon cancer, relatively few studies have examined rectal cancer in relation to use of nonsteroidal antiinflammatory drugs (NSAIDs). The authors evaluated the association between NSAIDs and distal large bowel cancer in African Americans and whites, using data from a population-based case-control study of 1,057 incident cases of adenocarcinoma of the sigmoid colon, rectosigmoid junction, and rectum and 1,019 controls from North Carolina (2001-2006). NSAID use was inversely associated with distal large bowel cancer in whites (odds ratio (OR) = 0.60, 95% confidence interval (CI): 0.46, 0.79). The inverse association was evident for all types of NSAIDs but was slightly stronger with prescription NSAIDs, particularly selective cyclooxygenase 2 inhibitors (OR = 0.38, 95% CI: 0.25, 0.56). Compared with whites, a relatively weak inverse association was found in African Americans (OR = 0.87, 95% CI: 0.55, 1.40), although odds ratio heterogeneity by race could not be confirmed (P = 0.21). In addition, the strength of the association with NSAIDs varied by tumor location, suggesting more potent effects for rectal and rectosigmoid cancers than for sigmoid cancer. The chemopreventive potential of NSAIDs might differ by population and by tumor characteristics.
American journal of epidemiology 11/2008; 168(11):1292-300. · 5.59 Impact Factor
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ABSTRACT: trans-Fatty acid consumption is known to have detrimental effects on cardiovascular health, but little is known about its role in digestive tract neoplasia. To investigate the association between colorectal adenomas and trans-fatty acid consumption, the authors utilized data from a cross-sectional study of 622 individuals who underwent complete colonoscopy between 2001 and 2002 at the University of North Carolina Hospitals. Participants were interviewed about demographic, lifestyle, and dietary factors thought to be related to colorectal cancer. trans-Fatty acid consumption, energy adjusted by the residual method, was categorized into quartiles based on its distribution in controls. Compared with participants in the lowest quartile of consumption, those in the highest quartile had an increased prevalence of colorectal adenomas, with an adjusted prevalence odds ratio of 1.86 (95% confidence interval: 1.04, 3.33). The authors further investigated the relation between trans-fatty acid consumption and colorectal neoplasia by examining the adenoma characteristics, with the adjusted prevalence odds ratios showing little or no difference by adenoma location, size, or number. These results suggest that consumption of high amounts of trans-fatty acid may increase the risk of colorectal neoplasia, and they provide additional support to recommendations to limit trans-fatty acid consumption.
American journal of epidemiology 09/2008; 168(3):289-97. · 5.59 Impact Factor
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ABSTRACT: Although antioxidant nutrients and oxidative DNA damage have been associated with carcinogenesis, few studies have investigated the factors that influence antioxidant intake and oxidative DNA damage in racially diverse populations. Demographic, behavioral, and diet-related psychosocial correlates of plasma antioxidant (carotenoids, vitamin C, and vitamin E) concentrations and oxidative DNA damage were examined using data from a cross-sectional study of 147 generally healthy, nonsmoking African American and white adults in North Carolina, aged 20 to 45 years. All participants completed self-administered demographic, diet, and health questionnaires and provided semifasting (> or = 6 hours) blood samples. Multivariate regression analyses were computed separately for each race to determine associations between the potential correlates with plasma antioxidant concentrations and oxidative DNA damage, separately. Our findings suggest appreciable differences by race. Only a few factors (age, supplement use, and several psychosocial factors) were associated with antioxidant concentrations in African Americans, whereas these and additional factors, including physical activity, waist circumference, and passive smoke exposure, were associated with antioxidant concentrations in whites. For oxidative DNA damage, passive smoke exposure was significantly associated with oxidative DNA damage in African Americans, and age and alcohol were significant in whites. In addition, the regression models generally explained more of the variance in plasma antioxidant concentrations and oxidative DNA damage in whites than in African Americans. Considering the salient correlates differed by race, this work has important implications for the design and implementation of future research studies investigating antioxidant nutrients and/or oxidative stress, especially those in racially diverse populations.
Nutrition research (New York, N.Y.) 09/2008; 28(9):565-76. · 1.20 Impact Factor
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ABSTRACT: Lung cancer is the leading cause of cancer-related mortality in the United States. Although supplements are used by half the population, limited information is available about their specific effect on lung cancer risk.
To explore the association of supplemental multivitamins, vitamin C, vitamin E, and folate with incident lung cancer.
Prospective cohort of 77,721 men and women aged 50-76 years from Washington State in the VITAL (VITamins And Lifestyle) study. Cases were identified through the Seattle-Puget Sound SEER (Surveillance, Epidemiology, and End Results) cancer registry.
Hazard ratios (HRs) for incident lung cancer according to 10-year average daily use of supplemental multivitamins, vitamin C, vitamin E, and folate. A total of 521 cases of lung cancer were identified. Adjusting for smoking, age, and sex, there was no inverse association with any supplement. Supplemental vitamin E was associated with a small increased risk of lung cancer (HR, 1.05 for every 100-mg/d increase in dose; 95% confidence interval [CI], 1.00-1.09; P = 0.033). This risk of supplemental vitamin E was largely confined to current smokers (HR, 1.11 for every 100-mg/d increase; 95% CI, 1.03-1.19; P < 0.01) and was greatest for non-small cell lung cancer (HR, 1.07 for every 100-mg/d increase; 95% CI, 1.02-1.12; P = 0.004).
Supplemental multivitamins, vitamin C, vitamin E, and folate were not associated with a decreased risk of lung cancer. Supplemental vitamin E was associated with a small increased risk. Patients should be counseled against using these supplements to prevent lung cancer.
American Journal of Respiratory and Critical Care Medicine 03/2008; 177(5):524-30. · 11.08 Impact Factor
