Does the gut microbiota play a key role in bone fragility?

The risk of so-called fragility fractures (sidenote: Fragility fractures Fragility fractures result from low-energy trauma (a mechanical force that would not ordinarily cause a fracture), such as a fall from standing height or less. These fractures are the main clinical consequence of osteoporosis, although they may occur in postmenopausal women even in the absence of osteoporosis.  ) (i.e. with no major trauma), largely linked to osteoporosis, increases with age, with one in two women and one in four men suffering an osteoporotic fracture at some point: fracture of the femoral neck after a very light fall, broken wrist as a result of minor trauma, vertebral compression, etc.

Bone is constantly remodeling itself and tends to be destroyed faster than it can be rebuilt after the age of 45. In addition to traditional bone protection methods such as a healthy diet and physical exercise, a new avenue is opening up: the gut microbiota, already implicated in bone health and the risk of osteoporosis. A new study has shown that our gut flora predicts the risk of ending up in a cast.

Gut bacteria: friend or enemy of our bones?

A healthy gut microbiota rests on a wide variety of gut bacteria. This diversity also has consequences for bone strength, say researchers who analyzed the microbiota of over 7,000 Finns. The verdict: the more diverse the microbiota, the lower the risk of fracture.

How can this link be explained? Among the many bacteria that colonize our gut, some have a beneficial effect, while others weaken our bones. Proteobacteria, already implicated in various types of inflammatory bowel disease and irritable bowel syndrome, may also promote more generalized inflammation in the body, and with it bone fragility.

Conversely, Tenericutes produce tiny fatty acids, including butyrate, which have a protective anti-inflammatory effect.

A balanced microbiota for strong bones?

The future of fragility fracture prevention may thus be a question of rebalancing your gut flora. In addition to an adequate intake of calcium and vitamin D, for healthy bones, take care of your “good” bacteria.

Despite these promising results, considerable work is still required to confirm a causal relationship between bacteria and fractures, and to understand how gut bacteria act to protect or weaken bones. In the meantime, for strong bones into old age, make sure to mind your gut.