Millions of people take supplements to help prevent bone loss, but a number of studies are looking at whether eating a healthy diet may be the best protection. Now a new study, published online by JAMA Internal Medicine, has looked at the bone-protective benefits of several high-quality types of diets, including the DASH diet (used to lower blood pressure) and the Mediterranean diet.
The study1 consisted of 90,014 postmenopausal women between the ages of 50 and 79, who were enrolled in the Women’s Health Initiative, a 40-center study in the United States. The women’s data was analyzed and scored on four diet indexes.
The authors reported that women who were in the highest fifth for adhering to a Mediterranean diet had a 20 percent lower risk for hip fractures than those in the lowest fifth. However, there was no association between a Mediterranean diet and total fracture risk.
As for the other three diet indexes, those who scored in the healthiest fifth of the group tended to have fewer hip fractures, though the results were not considered statistically significant.
“The results were surprising in so far as we did not see large associations between a healthy dietary pattern and fracture risk,” says the study’s lead author, Bernhard Haring, MD, of the University of Würzburg in Germany. However, it did suggest that a high quality diet of any type may lead to a lower risk, he says.
Several studies have shown lower rates of osteoporosis in Mediterranean countries compared with northern European countries, according to the study. A Mediterranean diet emphasizes fruits and vegetables, fish, nuts and monounsaturated fats, like olive oil as well as avoiding red and processed meats. Both plants and unsaturated fatty acids have been shown to benefit bone health, according to the study. Yet research looking specifically at diet and fracture risk has been mixed with some studies showing no benefit of following a Mediterranean diet.
“The findings on the Mediterranean diet and fractures in this study were interesting, but far from conclusive,” says Walter Willet, MD, PhD, chair, department of nutrition at the Harvard T. H. Chan School of Public Health, at Harvard, who wrote an accompanying editorial in the journal. “If there is truly a 20 percent reduction in fracture risk, this would be important. However, this relation still might have been due to chance, and better control for physical activity and other variables might have diminished the relationship.“
It was also worth nothing that none of the diets increased the risk of bone fractures, even though they didn’t emphasize dairy intake, which are good sources of calcium and vitamin D.
In his editorial, Dr. Willet wrote, “At a minimum the present findings provide assurance that widely recommended eating patterns do not increase the risk of fractures, even though some of these patterns do not emphasize the intake of dairy foods.”
Still there are plenty of other reasons why a Mediterranean diet is worth following. The diet has been associated with a reduction in cardiovascular disease and diabetes, as well as obesity, colorectal cancer, and dementia. 2 Because of a wealth of evidence, the US Dietary Guidelines Committee recommended Americans follow the Mediterranean diet and similar dietary patterns.3
2. Willet editorial http://archinte.jamanetwork.com/article.aspx?articleid=2504183