Could preventing osteoporosis be as simple as eating one yogurt every day?

Background: By age 65, 25% of women and 5% of men will have osteoporosis, which makes bones thin and brittle and can lead to fractures. As estrogen production drops in women after menopause, they become especially prone to the condition. Standard advice for prevention for both women and men includes weight-bearing exercise, avoiding smoking, moderating alcohol and consuming a nutritious diet rich in calcium and vitamin D. Dairy foods, especially when fortified with vitamin D, are rich in both nutrients—but whether yogurt is better for bones than, say, milk or cheese has been an open question.

Study: Researchers from Ireland used data from a study of more than 4,000 Irish men and women older than 60. They excluded anyone taking medications that affect bone health. The participants filled out questionnaires about their diets and lifestyles (including how often they ate certain foods, including yogurt) as well as health status. They were also given physical exams, including blood draws.

Results: Eating yogurt was strongly linked to osteoporosis prevention…

  • For women, consuming one serving (about one-half cup in the study) of yogurt a day, on average, was linked to a 39% reduced risk for osteoporosis.
  • For men, consuming one serving of yogurt a day on average was linked to a 52% reduced risk.

It wasn’t just that yogurt eaters got more calcium and vitamin D than those who ate little or no yogurt. The researchers adjusted for that statistically—and found that even people who had gotten just as much calcium and vitamin D, but not as much of it from yogurt, had higher rates of osteoporosis. The semiobvious conclusion: There is something about yogurt besides its calcium and vitamin D that protects bones…and that isn’t true about most other dairy foods.

Surprising result: Women who ate more yogurt were a tad fitter than those who ate less. In one test, for example, they could get up from a chair, walk about three yards, turn around and go back and sit down again faster than women who rarely ate yogurt. For men, there was no fitness difference.

Bottom line: What’s yogurt’s special sauce when it comes to strengthening bones? This kind of observational study can’t answer that question firmly, but the study authors have some definite ideas. They note that beneficial bacteria in fermented dairy products such as yogurt made with active cultures has been shown (in other studies) to increase bone mass density—the opposite of what happens in osteoporosis. Yogurt is also unusually rich in certain biologically active protein compounds called peptides that are also linked with stronger bones.

The authors also note that not all yogurt is healthful—some is laden with sugar. So if you want an easy daily habit that will protect your bones, go for yogurt–but choose your yogurt wisely.