Boosting calcium consumption spurs weight loss, according to a study published in the most recent issue of the British Journal of Nutrition, but only in people whose diets are calcium deficient.

Angelo Tremblay and his team at Université Laval's Faculty of Medicine made the discovery in a 15-week weight loss program they conducted on obese women. The participants consumed on average less than 600 mg of calcium per day, whereas recommended daily intake is 1000 mg. In addition to following a low calorie diet, the women were instructed to take two tablets a day containing either a total of 1200 mg of calcium or a placebo. Those who took the calcium tablets lost nearly 6 kg over the course of the program, the researchers found, compared to 1 kg for women in the control group.

"Our hypothesis is that the brain can detect the lack of calcium and seeks to compensate by spurring food intake, which obviously works against the goals of any weight loss program," said Angelo Tremblay, holder of the Canada Research Chair in Environment and Energy Balance. "Sufficient calcium intake seems to stifle the desire to eat more," he added.

Consuming sufficient calcium is therefore important to ensuring the success of any weight loss program. According to the researcher, over 50% of obese women who come to the clinic run by his research team do not consume the recommended daily intake.

Professor Tremblay and his team have studied the link between calcium and obesity for several years. Their first findings, published in 2003, revealed that women who consumed diets poor in calcium had more body fat, bigger waistlines, and higher bad cholesterol levels than those who consumed moderate or large amounts of calcium. A second study showed that the more people reduced their consumption of dairy products over the six-year period examined, the more weight and body fat they gained and the bigger their waistlines grew. In 2007, Angelo Tremblay and his team established a direct link between calcium and a lower cardiovascular risk profile among dieters.