Phytoestrogens are plant-derived compounds with structural similarity to human estrogen. They are most commonly found in soy products (isoflavones) and red clover. The rationale for using phytoestrogens in menopause is based on their weak estrogenic activity, which may help alleviate menopausal symptoms such as hot flashes and night sweats that result from declining endogenous estrogen levels.

Scientific evidence for the efficacy of phytoestrogens in supporting or treating menopausal symptoms is mixed but present. Several randomized controlled trials and meta-analyses have evaluated the effects of phytoestrogens, particularly soy isoflavones, on hot flashes. Some studies report a modest reduction in frequency and severity of vasomotor symptoms compared to placebo, while others show minimal or no effect. The North American Menopause Society and other clinical guidelines acknowledge that phytoestrogens may offer benefit for some women, but the overall effect size is generally small and not as robust as hormone replacement therapy.

Safety profiles are generally favorable, with few serious adverse effects reported in the short term. However, long-term safety data are limited, particularly regarding breast and endometrial health. In summary, while there is scientific evidence supporting the use of phytoestrogens for menopausal symptom relief, the strength of evidence is moderate, with benefits likely to be modest.