Protein and bone health

You could probably use some meat on your bones. Literally.

For many years there was a misconception in the nutrition community that protein intake compromised bone mass density (BMD). This idea stemmed mostly from the fact that increased protein may prompt a discharge of calcium into the urine. Based on this, many doctors and nutritionists jumped to the conclusion that protein must have a negative effect on BMD.

But times have changed. In the e-Alert “Good to the Bone” (11/6/03), I told you about a study in the American Journal of Clinical Nutrition that showed how postmenopausal women with the highest protein intake may actually have a significantly higher BMD compared to women with low amounts of protein in their diets.

Now a new study in the Journal of Clinical Endocrinology & Metabolism confirms those results. US Department of Agriculture researchers recruited 32 men and women over the age of 50 whose diets contained the recommended daily calcium intake of 800 mg. For nine weeks, subjects followed either a high-protein or low-protein diet, and were advised to decrease carbohydrate intake to balance calorie levels with the increase in protein.

At the end of the study period, researchers found that urinary calcium excretion was statistically the same in both groups. But when a bone growth factor was measured, those in the high-protein group had higher levels of the factor.

Contrary to the conventional wisdom that a high-protein diet may contribute to osteoporosis, the UDSA team concluded that such a diet “may have a favorable impact on the skeleton in healthy older men and women.”

Mainstream nutritionists who refuse to let go of the low-fat diet mindset often talk about the health hazards of low- carb/high-protein diets. Little by little we see that argument eroding, and this study just adds to that erosion.

To Your Good Health,
Jenny Thompson

Health Sciences Institute

Sources:
“Effect of Dietary Protein Supplements on Calcium Excretion in Healthy Older Men and Women” Journal of Clinical Endocrinology Metabolism, Vol. 89, No. 3, March 2004, ncbi.nlm.nih.gov
“Higher Protein Levels Could Strengthen Bones” NutraIngredients.com, 4/5/04, nutraingredients.com