Protein-Rich Dairy Foods Improve Bone Health During Dieting

CHEVY CHASE, Md.Obese premenopausal women who consume high levels of protein from dairy sources may help reverse bone loss often associated with calorie-restricted diets, according to a new study appearing in the January 2012 issue of Journal of Clinical Endocrinology & Metabolism.

Previous studies have shown that higher body weight is associated with greater bone mass and that weight loss through dieting can adversely affect bone health. For this study, researchers at McMaster University conducted a controlled, randomized weight-loss intervention trial involving 90 premenopausal overweight or obese women that was designed to achieve weight loss and be supportive of bone health. Participants were put on modest dietary calorie restriction and daily exercise, including aerobic and resistance training with varied intakes of protein and dairy foods. Researchers used dual-energy X-ray absorptiometry (DXA) scans to assess bone mineral density and content, and analyzed participants urine and blood samples to evaluate serum levels of several bone health biomarkers.

They found the consumption of diets higher in protein with an emphasis on dairy foods during a diet and exercise period positively affected markers of bone turnover, calcium, vitamin D status and bone metabolism in overweight and obese premenopausal women.

Our data provide a good rationale to recommend consumption of dairy foods to aid in high-quality weight loss, which we define as loss of fat as opposed to muscle, and the promotion of bone health in young women who are at the age when achieving and maintaining peak bone mass is of great importance," they said.