Dietary supplements and weight control in a middle-age population.

OBJECTIVES: Obesity is rapidly becoming a health problem of epidemic proportions, bringing with it a host of health concerns. This study investigates the association of long-term (10-year) use of 14 nutritional supplements, marketed as weight-control aids, with weight change over the past 10 years among individuals age 53 to 57 years. METHODS: Data are from the VITamins And Lifestyle (VITAL) cohort study of western Washington. Participants (n = 15,655) completed questionnaires about 10-year supplement use, diet, health habits, height, and present and former weights. The following supplements that are sometimes marketed for weight control or loss were examined: multivitamins; vitamins B6 and B12; chromium; coenzyme Q10, dehydroepiandrosterone, essential fatty acids (EFAs), fiber, garlic (Allium sativum), ginkgo (Ginkgo biloba), ginseng (Panax spp.), melatonin, soy, and St. John's wort (Hypericum perforatum). Linear regression was used to model 10-year change in weight from age 45 to ages 53-57, stratified by sex and body mass index (BMI, kg/m2) (normal, overweight, or obese) at age 45 years. Models were controlled for race/ethnicity, education, energy intake, physical activity, weight at age 45 years, and smoking. RESULTS: Among overweight or obese men and women, long-term use of multivitamins, vitamins B6 and B12, and chromium were significantly associated with lower levels of weight gain. For example, with chromium, weight gain in the past 10 years for obese men was 11.7 lb for no use, 6.1 lb for <150 microg/day (10-year average), and a weight loss of 3.1 lb for > or = 150 microg/day (p for trend, <0.05). Among obese women, weight gain was 14.1 lb, 7.9 lb, and 3.2 lb for the three groups respectively (p for trend, <0.01). CONCLUSIONS: These data suggest that long-term users of certain supplements experienced less weight gain than individuals who did not use the supplements. Further study is necessary before recommendations regarding these supplements can be made.