Associations between weight discrimination and the use of potentially harmful dietary supplements during the COVID-19 pandemic in the United States.

The dietary supplements industry disproportionately markets potentially harmful products promising weight loss, cleansing/detoxing, and boosted energy and immunity to women. The COVID-19 pandemic heightened consumer concerns around health and body weight, which may have increased women's risks of using supplements, particularly if they had a higher weight and experienced weight discrimination. This study aimed to estimate inequities in prevalence and change in use of weight-loss, cleanse/detox, immunity, and energy supplements in the first year of the pandemic and to assess the extent to which the relationship between weight and supplement use differs across discrimination experiences. We drew upon longitudinal data from cisgender women in the U.S. COVID-19 Pandemic Substudy of the Nurses' Health Study II and 3 and Growing Up Today Study cohorts, collected over 5 waves from April/May 2020 to April 2021 (N = 51,814). Modified Poisson generalized estimating equation models, adjusted for age, cohort, race/ethnicity, wave, and Census region, estimated the relative excess risk due to interaction (RERI) between weight status and weight discrimination on prevalence of supplement use. Weight status categories were derived from body mass index (BMI), and weight discrimination was assessed using the attributions item of the Everyday Discrimination Scale. Baseline prevalence of supplement use was 2.7% for weight-loss, 3.3% for cleanse/detox, 4.2% for energy, and 22.6% for immune. Respondents with BMIs of 25-29.9 kg/m and 30-34.9 kg/m who experienced weight discrimination had RERI values of 0.89 (95% CI 0.14, 1.65) and 1.00 (95% CI 0.25, 1.75) for weight-loss and 0.57 (95% CI 0.13, 1.02) and 0.60 (95% CI 0.19, 1.01) for energy supplements, respectively, indicating this group had excess risk of use compared to lower BMI respondents who experienced no weight discrimination. The findings demonstrate the disproportionate impact of weight discrimination on use of potentially harmful supplements among cisgender women with higher weights during the pandemic.