Discrepancies between the internet and academic literature regarding vitamin use for male infertility.

Background: The accuracy of online medical information is variable. A 2014 Cochrane review did not support a robust improvement in male infertility after antioxidant supplementation. Many subfertile men take vitamins in hopes of improving their fertility. We sought to evaluate the content of online information for male fertility vitamins, and compare this with the published literature.

Methods: We searched Google to assess online information regarding vitamins and male infertility. Websites were evaluated for authorship, content, claims and validity. We then reviewed the Recommended Daily Allowance and upper tolerable intake level for each vitamin, and compared this with the supplements actual content.

Results: Four websites were posted by an academic source, 7 private clinic, 31 industry, 8 were patient blogs and 50 other sources. Reproductive claims made by websites included: Improved sperm count: 65; improved pregnancy rates: 42; improved live birth rates: 9; healthier offspring: 18. Overall, 76 websites claimed some improvement in semen parameters; 85 claimed some improved reproductive outcome. 26 websites were supported by peer-reviewed literature. None of the supplements had more than the upper tolerable intake level of any of the vitamins, but several were over the RDA, most commonly zinc, vitamin B12 and selenium.

Conclusions: Many websites claim improvements in a variety of male reproductive outcomes after vitamin supplementation. These are often not supported by the medical literature. We need to provide evidence-based information to patients so that they can have realistic expectations of the benefits that vitamins may have on male reproductive outcomes.