“Estrobolome” is the name researchers give to the collection of gut bacteria and genes that can metabolize estrogen. It’s a young field, but it adds an intriguing piece to the story of how hormones are regulated.
How it works
Your liver packages used estrogen for disposal by attaching a chemical tag — a process called conjugation — and sends it to the gut via bile. Some gut bacteria produce an enzyme called beta-glucuronidase, which removes that tag. Once untagged, estrogen can be reabsorbed into the bloodstream instead of leaving the body.
So the makeup of your gut microbiome can influence how much estrogen is recycled versus excreted.
Why it might matter
In principle, an estrobolome that recycles too little or too much estrogen could contribute to conditions linked to estrogen levels. Researchers are investigating connections with breast cancer, endometriosis, polycystic ovary syndrome and symptoms of menopause.
After menopause, when the ovaries produce much less estrogen, the gut’s role in circulating estrogen becomes a larger share of a smaller total — one reason scientists are interested in the estrobolome in midlife.
What we don’t know yet
Most of the evidence so far comes from animal studies and associations in small human studies. It’s not yet clear how much the estrobolome changes hormone levels in practice, whether it can be deliberately shifted, or what an “ideal” estrobolome looks like. Be cautious of products claiming to “balance hormones through the gut” — the science doesn’t support specific claims like that yet.
What’s reasonable to do now
The habits that support a diverse microbiome in general are sensible regardless:
- Eat plenty of fiber from varied plant foods
- Include fermented foods such as yogurt, kefir and kimchi
- Avoid unnecessary antibiotics
- Limit heavy alcohol use
These have broad, well-established benefits — whatever the estrobolome research eventually shows.