Soy protein may reduce testosterone levels and impair fertility only in cases of excessive consumption, while a daily intake of 10 to 70 g of protein or 60 to 240 mg of isoflavones is safe.

noli's read

This claim aligns well with the current scientific consensus on soy consumption. A major meta-analysis published in 'Reproductive Toxicology' examined the impact of soy isoflavones on male hormones and found no significant effect on testosterone, even at relatively high doses. Concerns regarding 'feminization' or reduced male fertility appear to stem primarily from animal model studies or isolated clinical cases using extreme quantities, which are not representative of a normal human diet. The distinction made by the creator between moderate consumption (10-70g) and hypothetical excess is consistent with available observational data and randomized controlled trials. It is important to note that individual variability in isoflavone absorption may exist, but this does not call into question the safety at the indicated doses. The message skillfully avoids unnecessary alarmism while acknowledging the limits of consumption.

the sources

No named source held this one up — that absence is part of the verdict.