Scientists are great at coming up with new words, and I learned one recently: "Estrobolome!" 🔬 Your estrobolome is a group of gut bacteria that determine whether your oestrogen gets excreted or recycled.
When oestrogen is made in your body, or enters it, your liver tags it with a glucuronide molecule 🏷️, which marks it for disposal, shipping it into the gut in bile. But some specific gut bacteria (your estrobolome) produce an enzyme called beta-glucuronidase, which snips that tag off ✂️ to reactivate the oestrogen, and a portion is reabsorbed into your blood.
Your gut can recycle oestrogen back into circulation ♻️ rather than letting it go, and when oestrogen is plentiful, it does less of this - beta-glucuronidase activity falls, and more gets excreted instead. After menopause, the abundance of beta-glucuronidase drops as well, so that you lose the ovarian supply and some of the recycling system with it. 📉
🔄 What changes at menopause
Postmenopausal women have lower microbial diversity (than premenopausal women) and a species pattern which is more like men. These shifts travel alongside cardiometabolic markers ❤️ and loss of bone density. 🦴
✅ What it means, and what to do
🥦 Eat for microbial diversity. Aiming for 30 different plants a week as well as fermented food (see last week's blog) increases your microbiome diversity, which includes your estrobolome species.
🧪 Be sceptical of "menopause microbiome" test kits. There's no validated target species ratio to aim at yet.
💊 If you take hormone replacement therapy (HRT), keep doing it. The early data shows HRT shifts the gut back towards a premenopausal pattern in terms of microbial diversity and species.