Predictors of Skin, Hair, and Nail Supplement Use: Analysis of National Health and Nutrition Examination Survey (NHANES) Cross-Sectional Data

Approximately half of US adults use dietary supplements, often for dermatologic purposes. When survey respondents in a nationally representative population were asked the reasons for their use of a specific supplement, 87% chose "for healthy skin, hair, and nails." Despite widespread use, supplements have potential risks and lack regulatory safeguards. Because most supplement users choose to use them without the advice of a healthcare professional, it is important to identify factors predicting use. This study examined demographic predictors of skin, hair, and nail supplement use among 2015-2016 US National Health and Nutrition Examination Survey respondents, a nationally representative sample.Weighted descriptive analysis using χ2 tests examined group differences among respondents who took skin, hair, and nail supplements and those who did not take supplements in the past 30 days. Multivariable logistic regression models were performed to identify predictors of skin supplement use.Statistically significant differences in sex, education, income, and insurance status were observed between dermatologic supplement users and nonsupplement users (P < 0.0001). Factors significantly increasing the likelihood of skin supplement use included age between 30 and 60 years (odds ratio [OR] 1.788, 95% confidence interval [CI] 1.439-2.222), age older than 60 years (OR 4.983, 95% CI 3.838-6.469), having a college degree or above (OR 2.696, 95% CI 1.952-3.724), attending some college or above (OR 1.844, 95% CI 1.364-2.494), having an annual income of >$75,000 (OR 1.285, 95% CI 1.029-1.605), and having health insurance (OR 1.559, 95% CI 1.236-1.967). Male respondents were half as likely to use supplements, compared with females (OR 0.579, 95% CI 0.488-0.687).Factors such as age, education, income, and sex predict supplement use. Knowledge of such trends may help practitioners counsel patients on potential supplement risks and the many unknowns related to their use. Any patient could be using skin, hair, and nail supplements over the counter, including pregnant and older adult populations, as well as generally healthy patients. This would help protect patients from the possible dangers of supplements, including laboratory test interference and teratogenicity.