Research
Hormonal
Dietary phytoestrogens (specifically soy isoflavones) do not significantly alter circulating testosterone, free testosterone, or estradiol levels in healthy adult men, refuting concerns that soy intake causes feminization or hypogonadism.
If you are a healthy man, you can consume soy products without worrying about your testosterone levels dropping or developing feminine traits. Large-scale reviews confirm soy intake does not alter your sex hormone balance.
GoodRefutesHIGH confidence
A meta-analysis of 32 studies published in 2010 by Hamilton-Reeves et al. reported that the consumption of isoflavones had no significant effect on circulating testosterone or free testosterone levels in men [44], in agreement with other clinical trials evaluating phytoestrogen intake in PCa patients [37,39–41].
Why this rating
Supported by a meta-analysis of 32 studies and multiple RCTs, though some individual trials show minor SHBG changes.
Source
Effects of Dietary Phytoestrogens on Hormones throughout a Human Lifespan: A Review
Inés Domínguez‐López et al. · Nutrients · 2020
DOI 10.3390/nu12082456
narrative_reviewCited 182×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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