The gut, the estrobolome and your hormones

Gut bacteria producing β-glucuronidase deconjugate estrogens in the intestine, allowing reabsorption into circulation. That collection of genes is the estrobolome, and the mechanism is genuine — a 2025 systematic review found consistent dysbiosis and raised β-glucuronidase activity in endometriosis, producing a higher-estrogen environment.

Where the claims outrun the evidence. A 2026 systematic review and meta-analysis found that although the mechanism is biologically plausible, it does not translate into reproducible, large-scale changes detectable at the level of α-diversity or dominant phyla. In plain terms: the pathway is real, but commercial gut tests claiming to read your "estrogen metabolism" are measuring something far noisier than the marketing implies.

What follows practically is unglamorous and well supported anyway — dietary fiber and plant diversity shift β-glucuronidase activity. Worth doing; not worth paying for a test to justify.