Phytoestrogens are plant-derived compounds structurally similar to estradiol, the primary female sex hormone. Their use to support the vaginal body system has scientific basis, especially for alleviating symptoms associated with estrogen deficiency, such as those experienced during menopause. Multiple clinical studies have examined the effects of phytoestrogens—particularly isoflavones from soy and red clover—on vaginal health. Results suggest modest improvements in vaginal atrophy, dryness, and overall vaginal health, although the effects are generally less pronounced than those of conventional estrogen therapy. For example, systematic reviews and randomized controlled trials have reported that phytoestrogen supplementation can increase the maturation index of vaginal epithelial cells and reduce vaginal dryness compared to placebo. However, the quality and consistency of evidence vary, with some studies showing little or no benefit. The mechanisms proposed involve phytoestrogens binding to estrogen receptors in vaginal tissue, exerting weak estrogenic or anti-estrogenic effects depending on hormonal milieu. While phytoestrogens are generally considered safe, their efficacy is moderate and not universally accepted as standard care. Overall, scientific literature supports a role for phytoestrogens in supporting vaginal health, particularly for postmenopausal women seeking alternatives to hormone replacement therapy, but further high-quality research is needed to clarify optimal dosing and long-term outcomes.