PPernilla’sHolistic Library
Home›FAQs›What is an equol producer?
Soy Isoflavones

What is an equol producer?

An equol producer is someone whose gut bacteria can convert soy's daidzein into equol, a more biologically active compound -- only 30-50% of people can do this, which likely explains much of the variation in soy's hot-flash results.

Steamed edamame pods beside a block of white tofu
Fermented soy foods like miso, natto, and tempeh may partially bypass the need for equol-producing gut bacteria.

The short answer

Only 30-50% of people have gut bacteria capable of converting the soy isoflavone daidzein into equol, its more biologically active form. This distinction likely explains much of why soy's hot-flash research shows such variable individual results despite strong overall trial evidence: a 2012 meta-analysis found a 26.2% reduction in hot flash severity, and a 2024 meta-analysis of 61 studies found reductions of 40-75% at roughly 50mg per day. Fermented soy foods like miso, natto, and tempeh partially break down isoflavone glycosides during fermentation, possibly making them more usable without needing the equol-producing gut bacteria step at all.

Sources

  1. Quantitative Efficacy of Soy Isoflavones on Menopausal Hot FlashesBritish Journal of Clinical Pharmacology