Soy (Glycine max)

Evidence-based guide to Soy: benefits, dosage, safety and interactions.

Evidence

Strong: Multiple systematic reviews and meta-analyses (Taku 2012, Lethaby 2007 Cochrane) show consistent, statistically significant reductions in hot flush frequency and severity.

Traditional use and mechanism

Menopausal hot flush relief; bone density maintenance; cardiovascular support. Asian dietary staple for millennia — population studies show lower menopausal symptom rates in high-soy-consuming East Asian women.

Safety

Extensive safety data from population studies. Dietary soy safe even for most breast cancer survivors (Shanghai Breast Cancer Survival Study, Shu et al. 2009 JAMA — inverse association with recurrence). High-dose concentrated supplements (>100 mg/day) are a different category — require clinical guidance in hormone-sensitive conditions.