Does Soy Lower Testosterone?

As someone who deals with this topic on a near-daily basis, I appreciate more than most the significant public interest surrounding the consumption of soy-based foods and their influence on male testosterone levels.

All roads of inquiry lead to one question – Does soy lower testosterone?

Certainly, there is a portion of the population who believes it does and I don’t doubt that there are men out there who might otherwise be inclined to consume foods such as tofu, tempeh, edamame, and soymilk but refrain over concerns of this precise nature.

These concerns primarily stem from isoflavones, which soy is a uniquely rich source of. Isoflavones are naturally occurring plant compounds that are commonly classified as phytoestrogens although they differ from the hormone estrogen.

As a dietitian who champions diversity in protein intake as the path toward better health for men, this sentiment concerns me.