Objective: We investigated the effect of an equol-containing supplement on metabolism and aging, and climacteric symptoms, with respect to internally-produced equol.
Methods: A single center, randomized controlled trial (registration number: UMIN000030975) on 57 post-menopausal Japanese women (mean age: 56±5.37 years), was conducted. Twenty-seven women received the equol supplement, while the remaining received placebo. Metabolic and aging-related biomarkers were compared before and after the 3-month intervention. Climacteric symptoms were assessed every month using a validated self-administered questionnaire in Japanese post-menopausal women.
Results: Three months post intervention, the treatment group showed significant improvement in climacteric symptoms, when compared to the placebo group (81% vs. 53% respectively, p=0.045). We did not observe any beneficial effect on metabolic and aging-related biomarkers in the intervention group. However, in certain populations significant improvement in skin auto-fluorescence, which is a measurement of AGE skin products, and visceral fat area was observed, especially among equol producers.
Conclusion: Women receiving equol supplement showed improved climacteric symptoms. This study offered a new hypothesis that there may be a synergy between supplemented equol and endogenously-produced equol to improve skin aging and visceral fat in certain populations.