No consistent harm to thyroid, breast, endometrium or sperm
It found no consistent adverse effect on thyroid, breast, endometrium or sperm, nor on oestrogen in women or testosterone in men. Exposure before birth is marked thin.
What the study found
Isoflavones did not disrupt thyroid, breast, endometrium or sperm
A technical review screening 417 human reports found no consistent adverse effect on any of those, nor on oestrogen levels in women or testosterone in men. Its own authors mark two areas as thin rather than clear: exposure before birth, and effects in children.
The caveat · Lead author heads a soy-funded body
The lead author directs the Soy Nutrition Institute, funded by the United Soybean Board and its member companies; that is the largest declared conflict in this evidence base and it points toward the review's conclusion. Its verdicts are narrative judgments, not pooled effect estimates.
What we don't know
The lead author directs the Soy Nutrition Institute, funded by the United Soybean Board and its member companies; that is the largest declared conflict in this evidence base and it points toward the review's conclusion. Its verdicts are narrative judgments, not pooled effect estimates.