Taking Probiotics May Protect Your Bones as You Age
Gut microbes, not just calcium, are vital for bone health
A small study suggests a probiotic supplement may protect women from bone loss as they age – one of the many benefits offered by probiotics.
As people age, they face a greater risk of osteoporosis, a condition characterized by low bone mass or loss of bone mass over time. Bones lose their minerals and become porous. If the bones break down enough, people become vulnerable to breaks and fractures. People often associate calcium with bone health and therefore with preventing ailments like osteoporosis, but the study shows that gut microbes also play an important role in bone health – not just calcium. 
Researchers measured the women’s bone density at the beginning of the study, then randomly assigned them to take either a placebo or 2 daily doses of Lactobacillus reuteri (L. reuteri), an intestinal tract microbe that occurs naturally in most people, in freeze-dried form. 
The women, aged 75-80 years old, were all generally healthy but had low bone mineral density.
A year later, the scientists measured the participants’ bone density once again and found that the reduction in density in the shin bones of the women assigned to take L. reuteri was nearly half compared to the shin bones in the women assigned a placebo.
Lead author Dr. Anna G. Nilsson said it’s unclear why this occurred.
“Perhaps estrogens could be affected by probiotics, and there is some discussion about calcium absorption, a change in the calcium-regulating hormones.”
While encouraged by the findings, Nilsson said women should not start taking probiotics purely because of them, and that more research is needed. 
“This is the first study in humans. We need confirmatory studies. And we’ve only studied one strain of L. reuteri, the type used in animal studies.”
The study appears in the Journal of Internal Medicine.
Julie Fidler is a freelance writer, legal blogger, and the author of Adventures in Holy Matrimony: For Better or the Absolute Worst. She lives in Pennsylvania with her husband and two ridiculously spoiled cats. She occasionally pontificates on her blog.