Quiz Ref ID Unhealthy diet is a major risk factor for noncommunicable diseases globally, including type 2 diabetes mellitus, cardiovascular disease, and certain types of cancer.^1-3 In the United States, poor diet was estimated to be the leading cause of death and the third leading cause of disability-adjusted life-year loss.⁴ Consequently, evaluation of overall population trends in diet is important to identifying challenges and opportunities for improving the diet of all US adults.

Reduced levels of global DNA methylation are associated with genomic instability and are independent predictors of cancer risk. Little is known about the environmental determinants of global DNA methylation in peripheral blood. We examined the association between demographic and lifestyle factors and levels of global leukocyte DNA methylation in 161 cancer-free subjects enrolled in the North Texas Healthy Heart Study aged 45–75 years in 2008. We used in-person interviews for demographics and lifestyle factors, a self-administrated Block food frequency questionnaire for diet, and bioelectrical impedance analysis and CT-scan for body composition. We measured genomic DNA methylation using bisulfite conversion of DNA and pyrosequencing for LINE-1. Body composition measures including body mass index, waist circumference, areas of subcutaneous fat and visceral fat, percent of fat mass and fat-free mass were not associated with global genomic DNA methylation after controlling the effect of age, gender and race/e...

The health benefits and risks of dietary supplement use are controversial. To evaluate the association among dietary supplement use, levels of nutrient intake from foods and supplements, and mortality among U.S. adults. Prospective cohort study. NHANES (National Health and Nutrition Examination Survey) data from 1999 to 2010, linked to National Death Index mortality data. 30 899 U.S. adults aged 20 years or older who answered questions on dietary supplement use. Dietary supplement use in the previous 30 days and nutrient intake from foods and supplements. Outcomes included mortality from all causes, cardiovascular disease (CVD), and cancer. During a median follow-up of 6.1 years, 3613 deaths occurred, including 945 CVD deaths and 805 cancer deaths. Ever-use of dietary supplements was not associated with mortality outcomes. Adequate intake (at or above the Estimated Average Requirement or the Adequate Intake level) of vitamin A, vitamin K, magnesium, zinc, and copper was associated with reduced all-cause or CVD mortality, but the associations were restricted to nutrient intake from foods. Excess intake of calcium was associated with increased risk for cancer death (above vs. at or below the Tolerable Upper Intake Level: multivariable-adjusted rate ratio, 1.62 [95% CI, 1.07 to 2.45]; multivariable-adjusted rate difference, 1.7 [CI, −0.1 to 3.5] deaths per 1000 person-years), and the association seemed to be related to calcium intake from supplements (≥1000 mg/d vs. no use: multivariable-adjusted rate ratio, 1.53 [CI, 1.04 to 2.25]; multivariable-adjusted rate difference, 1.5 [CI, −0.1 to 3.1] deaths per 1000 person-years) rather than foods. Results from observational data may be affected by residual confounding. Reporting of dietary supplement use is subject to recall bias. Use of dietary supplements is not associated with mortality benefits among U.S. adults. National Institutes of Health.

Changes in DNA methylation may represent an intermediate step between the environment and human diseases. Little is known on whether behavioral risk factors may modify gene expression through DNA methylation. To assess whether DNA methylation is associated with different levels of physical activity, we measured global genomic DNA methylation using bisulfite-converted DNA and real-time PCR (MethyLight) for LINE-1 in peripheral blood of 161 participants aged 45–75 years enrolled in the North Texas Healthy Heart Study and levels of physical activity using an accelerometer (Actigraph GT1M Monitor). We found that individuals with physical activity 26–30 min/day had a significantly higher level of global genomic DNA methylation compared to those with physical activity ≤10 min/day (β = 2.52, 95% CI: 0.70, 4.35). However, the association was attenuated and became statistically insignificant after multivariate adjustment (β = 1.24, 95% CI: −0.93, 3.40). There were some suggestions of a positive association between physical activity and global genomic DNA methylation in non-Hispanics (β = 1.50, 95% CI: −0.08, 3.08) that warrants further investigation.

Unhealthful diet is one of the top contributors to poor health in the United States,¹ and disparities in diet quality by socioeconomic status can contribute to the nation’s health disparities. While overall diet quality has modestly improved in the past decade,² there are growing concerns that socioeconomic disparities persist in diet quality of US adults. Low-income individuals have not experienced the same improvements in diet quality as high-income individuals,^2,3 and for consumption of several foods, this disparity may have widened over time.³