Genistein is an isoflavone found predominantly in soy products and is classified as a phytoestrogen, meaning it has a chemical structure similar to that of human estrogen and can interact with estrogen receptors in the body. The vagina is highly responsive to estrogen, and estrogen deficiency, such as that seen in menopause, can lead to symptoms like vaginal dryness, atrophy, and discomfort. Scientific studies have explored the use of genistein and other soy isoflavones for alleviating these symptoms.

Clinical trials and observational studies have shown that genistein supplementation can improve vaginal cytology, increase vaginal lubrication, and reduce symptoms of vaginal atrophy in postmenopausal women. A 2013 randomized controlled trial published in Menopause demonstrated that daily supplementation with genistein significantly improved vaginal cell maturation and reduced vaginal dryness compared to placebo. Systematic reviews also suggest a moderate benefit, though results are sometimes mixed and may depend on dosage and individual variability.

While genistein is not as potent as pharmaceutical estrogen therapy, it presents a potentially safer alternative for women who cannot or prefer not to use hormone replacement therapy. The evidence base is sufficient to support genistein’s use for vaginal health, particularly in relation to menopause-associated symptoms, but more large-scale, high-quality trials are warranted to establish optimal dosing and long-term safety.