People who eat more dairy products have lower weights and seem to lose weight more easily, several observational studies published in recent year have suggested. But new research -- perhaps the best study to date on the issue -- shows calcium supplements have no effect on weight.
The study involved 340 obese or overweight adults, most of whom were women. They were assigned to take either 1,500 milligrams of calcium or a placebo with meals for two years. After the two years, there were no differences between the two groups in total body weight or body fat mass.
The dairy diet has been an especially popular topic in recent years, promoted by the dairy industry. Some scientists suggested that calcium can combine with fatty acids in the intestine to form insoluable soaps that are not absorbed. Others theorized that low calcium intake in the diet leads to more fat deposits. But the new study, by researchers at the Office of Dietary Supplements and Intramural Research at the National Institutes of Health, cast serious doubt on those theories.
"Even though there may be other important reasons, such as fracture prevention ... calcium supplementation is unlikely to have clinically significant efficacy as a preventive measure against weight gain in persons who are already overweight or obese," the authors wrote. It's still possible that increasing one's intake of dairy products, however, may effect weight.
The study is published in the Annals of Internal Medicine.
Illustration: Peter Bennett / For The Times