Tofu, made from soybeans, contains high levels of isoflavones—plant-derived compounds with estrogen-like activity. Hot flashes are a common symptom of menopause, resulting from declining endogenous estrogen levels. The scientific rationale for using tofu to support or treat hot flashes is based on the hypothesis that isoflavones can bind to estrogen receptors and exert mild estrogenic effects, potentially reducing the frequency and severity of hot flashes.

Several clinical trials and meta-analyses have evaluated the effectiveness of soy isoflavones (either as supplements or from soy foods like tofu) for menopausal hot flashes. The results are mixed: some studies report a modest but statistically significant reduction in hot flash frequency and intensity, while others find no meaningful benefit compared to placebo. The 2015 Cochrane review on phytoestrogens for menopausal symptoms concluded that phytoestrogens (including soy isoflavones) might reduce hot flash frequency and severity, but the evidence is inconsistent and often of low to moderate quality.

Overall, there is scientific interest and some supportive evidence for tofu (as a source of soy isoflavones) in managing hot flashes, but the effect is generally modest, and not all clinical trials have found benefit. Tofu's use is not rooted in traditional medicine for this specific purpose, but rather in modern nutritional and clinical research.