A new weight loss study conducted by researchers at Ben-Gurion University of the Negev (BGU) reveals that dieters who consumed milk or milk products lost more weight on average than those who consumed little to no milk products -- regardless of diet.
Researchers also found participants with the highest dairy calcium intake, equal to 12 oz. of milk or other dairy products (580 mg of dairy calcium), lost about 12 pounds (6 kg.) at the end of the two years.
By way of comparison, those with the lowest dairy calcium intake averaging about 150 mg dairy calcium, or about half of a glass, lost only seven pounds on average. The study was published in the current issue of the American Journal of Clinical Nutrition.
Beyond calcium, the researchers also found that blood levels of vitamin D independently affected weight loss success. Vitamin D levels increased among those who lost more weight. The dietary intervention study also confirmed other research that overweight participants have lower blood levels of vitamin D.
More than 300 overweight men and women, aged 40 to 65, took part in the study that evaluated low fat, Mediterranean or low-carb diets for two years. Dr. Danit Shahar, of BGU's S. Daniel Abraham Center for Health and Nutrition and the Faculty of Health Sciences, led the study, which was part of the Dietary Intervention Randomized Control Trial (DIRECT) conducted at the Nuclear Research Center in Israel.
The vitamin D factor
"It was known that overweight people had lower levels of serum vitamin D, but this is the first study that actually shows that serum Vitamin D increased among people who lost weight," according to Dr. Shahar. "This result lasted throughout the two years that the study was conducted, regardless of whether they were on a low-carb, low fat or Mediterranean diet."
Vitamin D increases calcium absorption in the bloodstream and in addition to sun exposure can be obtained from fortified milk, fatty fish and eggs. Americans generally consume less than the recommended daily requirement of Vitamin D, which is found in four glasses of milk (400 international units).