A recent meta-analysis of 12 randomised controlled trials (RCTs) involving 1,183 post-menopausal women revealed that probiotic supplementation significantly improved bone health.
The study, conducted by researchers at the Peking Union Medical College Hospital, found that probiotics increased bone mineral density (BMD) in both the lumbar spine and hip while reducing markers of bone breakdown, such as collagen type 1 cross-linked C-telopeptide (CTX).
These benefits were especially pronounced in women with mild bone loss — known as osteopenia — compared to those with severe bone loss or osteoporosis. The findings suggested that probiotics could be a promising low-risk intervention for bone health in postmenopausal women.
Why bone health declines after menopause
Postmenopausal women face a high risk of osteoporosis, a condition characterised by weakened bones and a higher likelihood of fractures. This increased vulnerability is largely due to a decline in oestrogen levels, which play a critical role in maintaining bone strength.
During the early post-menopausal years, women can lose up to 5% of their bone density annually, leaving them more susceptible to fractures, particularly in the spine and hips. Although pharmaceutical treatments are available, their long-term use is often limited by side effects and poor adherence, driving interest in alternative strategies such as probiotics.
How probiotics influence bone health
Probiotics are live microorganisms that offer health benefits when consumed in sufficient quantities. While they are most commonly associated with gut health, research has shown that they can also influence bone metabolism through several mechanisms.
These include reducing inflammation that accelerates bone loss, enhancing the absorption of nutrients necessary for bone formation, and promoting the production of short-chain fatty acids that help balance bone formation and breakdown.
Animal studies have demonstrated that probiotics can improve bone density in models of osteoporosis but human research, especially research focused on post-menopausal women, has been inconsistent.
Probiotics’ impact on BMD and bone turnover markers
The meta-analysis examined the impact of probiotics on BMD and bone turnover markers (BTMs), which reflect the processes of bone formation and resorption.
The results showed that women who took probiotics had significantly higher BMD in the lumbar spine and hip compared to those in the control group.
This improvement was more pronounced in women with osteopenia, suggesting that probiotics might be particularly effective in the early stages of bone loss.
The analysis also found that probiotics reduced CTX, a marker of bone resorption, and bone-specific alkaline phosphatase (BALP), which is linked to overall bone turnover. However, other markers such as osteocalcin (OC) and receptor activator of nuclear factor-κB ligand (RANKL) did not show significant changes, indicating that probiotics primarily influence bone resorption rather than formation.
Factors influencing probiotics’ effectiveness
The duration and dosage of probiotic supplementation appeared to play a critical role in determining its effectiveness.
Prolonged supplementation of over 12 months yielded greater improvements in BMD than shorter treatment periods.
Additionally, higher doses (at least one billion colony-forming units or CFUs per day) were more effective than lower doses.
The researchers also observed regional differences, with European women showing more significant improvements in BMD compared to Asian women.
This variation could be attributed to differences in gut microbiota composition, dietary habits, or genetics, although further research is needed to fully understand these disparities.
Implications for businesses and healthcare providers
These findings have practical implications for businesses and healthcare providers. Probiotic manufacturers have an opportunity to develop targeted products for bone health, particularly those with higher dosages and designed for long-term use.
Healthcare providers, meanwhile, can consider probiotics as part of a broader strategy for managing bone health in post-menopausal women, especially for those hesitant to use traditional medications.
The study also highlighted the need for further research to identify specific probiotic strains and combinations that are most effective for improving bone health.
Limitations and conclusions
Despite its promising results, the study had several limitations. The included trials exhibited significant variability in methodology, and many involved co-interventions, such as probiotics combined with vitamin D or calcium. This made it difficult to isolate the effects of probiotics alone.
Additionally, the specific strains of probiotics responsible for the observed benefits remained unclear.
Future research should focus on longer-term studies, strain-specific effects, and the role of gut microbiota in individual responses to probiotics.
The researchers concluded: “Probiotic supplementation may serve as an alternative approach to decelerate bone mass deterioration in post-menopausal women with osteopenia. In addition, administration of probiotics could decrease levels of CTX and BALP. In the future, more research is needed to validate these findings, and specific strains beneficial for bone health in postmenopausal women need to be further explored.”
Source: Frontiers in Endocrinology
“Effects of probiotic supplementation on bone health in postmenopausal women: a systematic review and meta-analysis”
https://doi.org/10.3389/fendo.2024.1487998
Authors: Fang Wang, et al.
