Top consumer uses of bestselling, single-ingredient vitamin and mineral supplements.

Objective: Vitamin and mineral supplements are widely used for self-care of a variety of medical conditions, but little is known about the specific conditions for which they are used. This study mined consumer product reviews to determine specific ways vitamin and mineral supplements are being used therapeutically.

Design/setting: A cross-sectional analysis of user reviews for top-selling, single-ingredient vitamin and mineral products from a popular online retailer was performed to identify the most frequently appearing words associated with medical conditions. Results of individual analyses were compared to achieve consensus on the top, relevant keywords for each supplement. The full text of the reviews was searched for these keywords to distinguish whether they referred to therapeutic uses or adverse effects.

Results: A total of 14 vitamin and 11 mineral supplements were analyzed. The number of user reviews for the analyzed products varied from 41 for manganese to over 5000 for biotin and vitamin D (median = 547 reviews per product). Cohen's kappa test for investigator-selected keywords related to medical conditions was generally greater than 0.6, indicating good interrater reliability. From these lists, the top consumer self-care uses were identified for 24 supplements. Commonly reported adverse effects were also noted for several products.

Conclusion: This study used data mining to identify the top ways consumers use an array of bestselling, single-ingredient vitamin and mineral supplements. These results can provide healthcare and nutrition professionals with information to anticipate the supplement-related education needs of patients and provide researchers with priority areas for clinical studies.