Trends in Daily Use of Biotin Supplements Among US Adults, 1999-2016

Over-the-counter biotin supplements, especially in high dosages (≥5 mg/d, or 166-fold greater than the dietary recommendation of 30 μg/d), are widely available and marketed as having health benefits such as stimulating growth of hair and nails. The US Food and Drug Administration (FDA) issued a safety communication in 2017 warning that high-dosage biotin supplement use may interfere with laboratory test accuracy.¹ To understand the potential clinical implications of high-dosage biotin supplement use, we characterized the prevalence and trends in use of 1 mg/d or greater and 5 mg/d or greater of biotin among US adults from 1999 to 2016. A biotin dosage of 1 mg/d or greater was chosen because lower dosages (<1 mg/d) are unlikely to interfere with laboratory tests; a dosage of 5 mg/d or greater was studied because biotin supplements for hair and nail growth often contain 5 mg/d or more.

Repeated cross-sectional surveys from the nationally representative National Health and Nutrition Examination Survey (NHANES) were used to assess trends in self-reported biotin supplement use of 1 mg/d or greater and 5 mg/d or greater from 1999 to 2016 (9 survey cycles). In each cycle, NHANES sampled noninstitutionalized US residents through a complex, stratified, multistage probability sampling design with certain populations overrepresented (overall response, 74%).² Participants provided informed consent.² Because the data are publicly available and anonymized, the University of Minnesota considered the study exempt from ethics review.

Daily supplement intake during the past 30 days was queried via in-person interviews, and participants were asked to show supplement bottles to aid in reporting.² Mean total daily biotin supplement intake was calculated, including biotin in multivitamin/multimineral formulations. For the present analysis, we excluded participants who were younger than 20 years, were pregnant, or had inadequate supplement information.

Statistical analysis was performed using Stata version 14.1 (StataCorp). The prevalences of biotin supplement use of 1 mg/d or greater and 5 mg/d or greater were calculated overall and by subgroups (ie, sex, race/ethnicity, and age category). Prevalence estimates and 95% CIs were weighted to be nationally representative and are reported as percentages. Linear and quadratic P values for trends were calculated across all 9 survey cycles by modeling survey cycle as a continuous variable. A 2-sided P < .05 was used as the threshold for statistical significance.

The number of participants in each survey cycle ranged from 4580 to 6145 (Table). The overall self-reported prevalence for 1 mg/d or greater biotin use increased from 0.1% (95% CI, 0.0%-0.5%) in 1999-2000 to 2.8% (95% CI, 1.9%-3.9%) in 2015-2016 (linear P < .001 for trend) (Table). Biotin use of 5 mg/d or greater was not reported before 2007-2008; the overall prevalence for 5 mg/d or greater increased from 0.1% (95% CI, 0%-0.2%) in 2007-2008 to 0.7% (95% CI, 0.5%-1.0%) in 2015-2016 (linear P < .001 for trend). Notable increases in prevalence were reported among women and older adults (≥60 years) for both 1 mg/d or greater and 5 mg/d or greater. In 2015-2016, the prevalences for 1 mg/d or greater and 5 mg/d or greater among women aged 60 years or older were 7.4% (95% CI, 4.6%-11.6%) and 2.3% (95% CI, 1.1%-4.7%), respectively.

Among US adults, the prevalence of self-reported biotin supplement use of 1 mg/d or greater and 5 mg/d or greater increased, particularly among women and older adults. While prevalence of use was still quite low, these findings are concerning in light of the 2017 FDA safety communication that described the potential of biotin interference to cause inaccurate laboratory results, including falsely low troponin results that could lead to missed or delayed myocardial infarction diagnoses.¹ In this context, high-dosage biotin supplement use among older women is particularly worrisome because cardiac events are frequently missed in this population.³ A prior NHANES study, which examined the prevalence of biotin supplement use of greater than 0 mg/d from 1999 to 2012, reported that use was stable in this period.⁴ The present analysis, which reports increasing trends of biotin supplement use from 1999 to 2016, provides more recent data and investigates biotin intake at thresholds that may interfere with laboratory results (ie, ≥1 and ≥5 mg/d).⁵ Study limitations include self-reported biotin use and poor precision due to small numbers of biotin users in some subgroups.

Corresponding Author: Danni Li, PhD, Department of Laboratory Medicine and Pathology, University of Minnesota, 420 Delaware St SE, MMC 609, Minneapolis, MN 55455 (dannili@umn.edu).

Accepted for Publication: April 30, 2020.

Author Contributions: Dr Rooney had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Li, Basta, Lutsey.

Acquisition, analysis, or interpretation of data: Li, Rooney, Burmeister, Lutsey.

Drafting of the manuscript: Li.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Rooney, Lutsey.

Administrative, technical, or material support: Li, Lutsey.

Supervision: Li.

Conflict of Interest Disclosures: Dr Li reported receipt of honoraria and other remuneration from Abbott Diagnostics and Diasorin. No other disclosures were reported.

Funding/Support: Dr Rooney was support by training grant T32HL007779 from the National Heart, Lung, and Blood Institute.

Role of the Funder/Sponsor: The National Heart, Lung, and Blood Institute had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication.

Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institutes of Health or the US Department of Health and Human Services.