Starchy Vegetables and Metabolic Syndrome in Costa Rica.

Only a few studies primarily examined the associations between starchy vegetables (other than potatoes) and metabolic syndrome (MetS). We aimed to evaluate the association between starchy vegetables consumption and MetS in a population-based sample of Costa Rican adults. We hypothesized that a higher overall intake of starchy vegetables would not be associated with higher MetS prevalence. In this cross-sectional study, log-binomial regression models were used to estimate prevalence ratios (PRs) of MetS across quintiles of total, unhealthy, healthy starchy vegetables, and individual starchy vegetables (potatoes, purple sweet potatoes, etc.), among 1881 Costa Rican adults. Least square means and 95% confidence intervals (CIs) from linear regression models were estimated for each MetS component by categories of starchy vegetable variables. Higher intakes of starchy vegetables were associated with a higher prevalence of MetS in crude models, but no significant trends were observed after adjusting for confounders. A significant inverse association was observed between total starchy and healthy starchy vegetables consumption and fasting blood glucose. In this population, starchy vegetables might be part of a healthy dietary pattern.

Association of Degree of European Genetic Ancestry With Serum Vitamin D Levels in African Americans.

Circulating levels of vitamin D are generally lower in African Americans than in US whites, and 1 prior analysis carried out in a small number of African Americans suggested that, within this population, vitamin D levels may be related to the degree of genetic admixture. We assessed the association between percentage of European ancestry and serum vitamin D level (assessed in 2013-2015) among 2,183 African-American women from the Black Women's Health Study whose DNA had been genotyped for ancestry-informative markers. ADMIXMAP software was used to estimate the percentage of European ancestry versus African ancestry in each individual. In linear regression analyses with adjustment for genotype batch, age, body mass index, supplemental vitamin D use, ultraviolet B radiation flux in the participant's state of residence, and season of blood draw, each 10% increase in European ancestry was associated with a 0.67-ng/mL increase in serum vitamin D concentration (95% confidence interval: 0.17, 1.17). The association was statistically significant only among women who were not taking vitamin D supplements (for each 10% increase in European ancestry, ß = 0.86, 95% confidence interval: 0.14, 1.57). Among African Americans, use of vitamin D supplements may help to reduce vitamin D deficiency associated with genetic ancestry.

Associations of Dietary Long-Chain ω-3 Polyunsaturated Fatty Acids and Fish Consumption With Endometrial Cancer Risk in the Black Women's Health Study.

Dietary long-chain (LC) ω-3 polyunsaturated fatty acids (PUFAs), which derive primarily from intakes of fatty fish, are thought to inhibit inflammation and de novo estrogen synthesis. This study prospectively examined the associations of dietary LC ω-3 PUFAs and fish with endometrial cancer risk in 47,602 African-American women living in the United States, aged 21-69 years at baseline in 1995, and followed them until 2013 (n = 282 cases). Multivariable-adjusted Cox regression models estimated hazard ratios and 95% confidence intervals for associations of LC ω-3 PUFA (quintiled) and fish (quartiled) intake with endometrial cancer risk, overall and by body mass index (BMI; weight (kg)/height (m)(2)). The hazard ratio for quintile 5 of total dietary LC ω-3 PUFAs versus quintile 1 was 0.79 (95% confidence interval (CI): 0.51, 1.24); there was no linear trend. Hazard ratios for the association were smaller among normal-weight women (BMI <25: hazard ratio (HR) = 0.53, 95% CI: 0.18, 1.58) than among overweight/obese women (BMI ≥ 25: HR = 0.88, 95% CI: 0.54, 1.43), but these differences were not statistically significant. Fish intake was also not associated with risk (quartile 4 vs. quartile 1: HR = 0.86, 95% CI: 0.56, 1.31). Again hazard ratios were smaller among normal-weight women (HR = 0.65) than among overweight/obese women (HR = 0.94). While compatible with no association, the hazard ratios observed among leaner African-American women are similar to those from recent prospective studies conducted in predominantly white populations.

Prospective study of dietary fat and risk of uterine leiomyomata.

BACKGROUND: Uterine leiomyomata (UL) are the primary indication for hysterectomy and are 2-3 times more common in black than white women. High dietary fat intake has been associated with increased endogenous concentrations of estradiol, a sex steroid hormone that is known to influence UL risk. OBJECTIVE: We assessed the relation of dietary fat intake (total, subtypes, and selected food sources) with UL incidence. DESIGN: Data were from the Black Women's Health Study, a prospective cohort study. Over an 8-y period (2001-2009), 12,044 premenopausal women were followed for a first diagnosis of UL. Diet was assessed via a food-frequency questionnaire in 2001. Cox regression models were used to compute incidence rate ratios (IRRs) and 95% CIs with adjustment for potential confounders. RESULTS: During 75,687 person-years of follow-up, there were 2695 incident UL cases diagnosed by ultrasound (n = 2191) or surgery (n = 504). Intakes of total fat and fat subtypes were not appreciably associated with UL risk overall, although statistically significant associations were observed for specific saturated (inverse) and monounsaturated and polyunsaturated (positive) fatty acids. With respect to polyunsaturated fats, the IRR for the highest compared with lowest quintiles of marine fatty acid intake [the sum of omega-3 (n-3) polyunsaturated fatty acids eicosapentanoic acid, docosapentaenoic acid, and docosahexaenoic acid] was 1.18 (95% CI: 1.05, 1.34; P-trend = 0.005). The IRR for the highest compared with lowest categories of dark-meat fish consumption was 1.13 (95% CI: 1.00, 1.28). CONCLUSIONS: In US black women, the most consistent associations of fat intake with UL were small increases in risk associated with intakes of long-chain omega-3 fatty acids. Future studies are warranted to confirm these findings and elucidate which components of fatty foods, if any, are related to UL risk.

Coffee, tea, and alcohol intake in relation to risk of type 2 diabetes in African American women.

BACKGROUND: Numerous studies have reported inverse associations of coffee, tea, and alcohol intake with risk of type 2 diabetes, but none has reported results separately among African American women. OBJECTIVE: We prospectively examined the relation of coffee, tea, and alcohol consumption to diabetes risk in African American women. DESIGN: The study included 46,906 Black Women's Health Study participants aged 30-69 y at baseline in 1995. Dietary intake was assessed in 1995 and 2001 by using a validated food-frequency questionnaire. During 12 y of follow-up, there were 3671 incident cases of type 2 diabetes. Relative risks (RRs) and 95% CIs were estimated by using Cox proportional hazards models adjusted for diabetes risk factors. RESULTS: Multivariable RRs for intakes of 0-1, 1, 2-3, and ≥4 cups of caffeinated coffee/d relative to no coffee intake were 0.94 (95% CI: 0.86, 1.04), 0.90 (95% CI: 0.81, 1.01), 0.82 (95% CI: 0.72, 0.93), and 0.83 (95% CI: 0.69, 1.01), respectively (P for trend = 0.003). Multivariable RRs for intakes of 1-3, 4-6, 7-13, and ≥14 alcoholic drinks/wk relative to never consumption were 0.90 (95% CI: 0.82, 1.00), 0.68 (95% CI: 0.57, 0.81), 0.78 (95% CI: 0.63, 0.96), and 0.72 (95% CI: 0.53, 0.98), respectively (P for trend < 0.0001). Intakes of decaffeinated coffee and tea were not associated with risk of diabetes. CONCLUSION: Our results suggest that African American women who drink moderate amounts of caffeinated coffee or alcohol have a reduced risk of type 2 diabetes.