Patterns of Dietary Supplement Use for Weight Loss Among U.S. Adults With Obesity: NHANES 2007-2020.

Abstract

Background: Dietary supplements are commonly marketed for weight loss, yet contemporary national data remain limited on the prevalence of use, types of products used, and whether use is provider-recommended among U.S. adults with obesity.

Methods: We conducted a cross-sectional analysis using data from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2020. Participants included adults with obesity. They were asked about behaviors on dietary supplements for weight loss. We estimated survey-weighted prevalence overall and by survey cycle, assessed linear trends over time, and used survey-weighted multivariable logistic regression to examine associations with age, sex, race/ethnicity, education, and poverty-income ratio. Among users, we described whether supplement use was recommended by healthcare providers and summarized supplement categories.

Results: Among 27,116 adults with obesity, 1706 reported using dietary supplements for weight loss. The survey-weighted prevalence of weight-loss supplement use was 5.9% and varied across survey cycles (p for trend = 0.003). Compared with adults aged 20-39 years, odds of use were lower among those aged 40-59 years (adjusted odds ratio [aOR] 0.60, 95% CI 0.45-0.80) and ≥ 60 years (aOR 0.15, 95% CI 0.11-0.22). Females had higher odds of use than males (aOR 1.46, 95% CI 1.13-1.87). Education was positively associated with use, whereas poverty-income ratio was not significantly associated. The use differed by race/ethnicity, with non-Hispanic White adults having lower odds of use compared with Hispanic adults. Among users, 81% reported use without medical advice, and it was more common among males and younger adults. The most frequently used supplements included multivitamin-minerals (28.8%), botanical products (20.0%), and single vitamins (15.2%).

Conclusions: Approximately 6% of U.S. adults with obesity reported using dietary supplements for weight loss, most without clinician recommendation and with significant demographic differences. Routine clinical assessment of supplement use and counseling regarding limited efficacy and potential safety concerns are warranted.