Gut microbiome and bone
Also called: microbiome-bone axis, probiotics for bone
What it means
The gut microbiome-bone axis describes how bacteria living in your gut may influence bone health through effects on hormones and the immune system, though the science is still emerging.
Understanding this connection can help you focus on well-supported habits, like eating fermented foods and fibre, rather than spending money on unproven stool tests or generic probiotics for your bones.
Researchers have found that gut bacteria can influence bone in a few ways: they affect how your body handles oestrogen, and they interact with your immune system in ways that reach bone tissue. Studies in animals raised without any gut bacteria, or treated with antibiotics, show noticeable changes in bone mass, which is part of why scientists think this connection is real and worth studying.
In people, a few trials have tested specific probiotic strains, including certain Lactobacillus reuteri and Lactobacillus paracasei strains, in postmenopausal women. These showed reduced bone loss over 12 months. But this doesn't mean any probiotic on a store shelf will do the same thing — the effects seen so far are specific to particular strains, so a general recommendation to 'take a probiotic' isn't really supported.
It's also worth knowing what isn't established: there's no good evidence that stool testing can tell you which supplement to take, or that a microbiome panel should be used to guide your bone plan. If you want a lower-risk, better-supported way to support gut health that may connect to bone, eating fermented foods and getting enough fibre fits the current evidence better than chasing a specific probiotic product.
How sure is this?
Graded Emerging Evidence: Promising research, but findings are still developing and may be primarily from laboratory or animal studies. Read each study with its grade in mind. One study is a piece of the picture, not the whole of it.
Where the Academy teaches it
This page is the short version. The lessons teach it in full, with the context around it and a quiz to lock it in.
Questions people ask about this
No, you don't need to cut out spinach, beans or grains. These foods do contain compounds like oxalates and phytates that bind minerals within that same meal, but the effect is small, limited to that meal, and easily managed with normal cooking. The real risks to your bones come from eating too little overall, not from eating too many plants.
Read the full answer →Related words
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Estrogen is a hormone that protects bone by keeping bone-removing cells in check. Falling estrogen, especially at…
Leaky gut, or intestinal permeability, means the lining of the intestine lets more substances pass through than it…
Inflammatory bowel disease (IBD) covers conditions like Crohn's and ulcerative colitis, where gut inflammation and…
Menopause is when your periods stop and estrogen levels drop sharply, which speeds up bone loss because the cells…
Education only, not medical advice. Decisions about tests, medications and treatment belong with your own doctor. OsteoStrong does not diagnose, treat or cure any disease.
