Is there a link between dietary phytoestrogens and reproductive health in men? A meta‐analysis of data from the USA and China

Abstract

SummaryThe human health implications of exposure to environmental pollutants and food components (e.g. phytoestrogens) that mimic the female hormone 17β‐estradiol (xenoestrogens) are a subject of significant debate. In this study, we use published data on human dietary phytoestrogen intake and sperm concentrations in the USA and China to assess effects on sperm concentration as a marker of male reproductive health. Comparison of the phytoestrogen intake and sperm concentration trends shows that in the USA phytoestrogen intake has increased from 0.8 mg day−1 in 1993 to 13.7 mg day−1 in 2005 and sperm concentration is trending down (not statistically significant), whereas in China phytoestrogen intake has decreased from 64.7 mg day−1 in 1991 to 15.6 mg day−1 in 2008, and the sperm concentration has increased from 55 × 106 mL−1 in 1999 to 74 × 106 mL−1 in 2008. We present this as evidence that phytoestrogen intake via food might, at least in part, be responsible for sperm concentration trends.