Research
S-equol for Menopause: Evidence, Interactions and Cautions
S-equol is an ingredient used in menopause supplements marketed to women. Below is what it has actually been studied for, how strong that evidence is, the drug interactions and cautions on record, and the primary source our grade rests on — all drawn from the HerWellReport ingredient dataset.
Also sold as: S-equol; equol; daidzein metabolite
What the evidence says about S-equol
A 2019 systematic review and meta-analysis pooled five randomised trials in 728 women and reported that supplementing equol significantly lowered hot flush scores, with the authors arguing that whether a woman can make equol herself is the main reason soy isoflavone trials disagree. Three of the five trials found a significant benefit and two did not, the trials were small, and the target group is narrow — the benefit is claimed specifically for equol non-producers. The Menopause Society's 2023 nonhormone therapy position statement names the soy metabolite equol on its not-recommended list (Level II), judging the evidence mixed and the studies limited. It has not been studied for bladder leakage.
The grade "limited for hot flushes; none for stress incontinence" means: limited — One or two small human trials, or trials for a closely related outcome. none — No human trial evidence we could find for this use. Grades are explained in full on our methodology page.
Read the primary source this grade rests on (opens in a new tab).
S-equol drug interactions
No documented drug interactions in the sources we checked. That is not the same as proof of safety alongside your medication — it usually means the question has not been studied. Ask a pharmacist before combining it with prescription drugs.
Who should be careful with S-equol
- A trial reported abdominal distension and thickening of the womb lining at 10 to 20 mg daily
- discuss with your doctor before use if you have a hormone-sensitive cancer, as equol binds oestrogen receptors
Read more on HerWellReport
This entry is generated from row "S-equol" of the HerWellReport ingredient dataset (v2.1, updated 2026-09-23). The dataset is free to reuse under CC BY 4.0 — how to cite it. Ingredient evidence is not evidence for any finished product, and nothing here is medical advice.