Calcium and Weight Loss
Michael Zermel and Hang Shi of the Nutrition Institute of the University of Tennessee at Knoxville decided to run some tests on that good old standby, the lab mouse. They bred some mice to be obese and then fed them diets high is fat and sugar for six weeks. The mice had a 27% increase in body fat.
The mice were then divided into three groups and put on a diet. One group was given calcium supplements; another group medium and high amounts of dry nonfat milk; and a third group was on the diet alone. The group without dairy products or calcium supplements lost 8% of their body fat; the group on calcium supplements lost 42% of their body weight, while the group using the dry milk lost 60% of their body weight.
Data from the National Health and Nutrition Examination Survey have shown a consistent relationship between calcium consumption and body weight. The most recent survey shows people who consume the least amount of calcium are six times more likely to be overweight than those who consume the most calcium. Most Americans consume only one half the daily recommended amount of calcium.
Zermel, the director of the Nutrition Institute did a study on humans that was funded by the National Dairy Council and published in “Obesity Research.”
The people were put on a low calorie diet and divided into three groups. The first group took in 400-500 mg of calcium a day and lost 15 lbs. in 6 months. The second group added 800 mg of a calcium supplement and lost 24 lbs.
The last group consumed 1200 mg of calcium a day in calcium found in food and lost 24 lbs. This group also lost a higher percentage of body fat and belly fat.
An even newer study put three groups of people on a diet for 24 weeks. Those getting 430 mg of calcium a day lost 15 lbs.; those taking a 1200 mg calcium supplement lost 19 lbs., and those who consumed 1100 mg of dairy calcium lost 24 lbs.
Researchers are not sure what causes calcium to be of such benefit for weight loss but Zermel theorizes that when there isn’t enough calcium in the diet the body responds by releasing hormones to conserve the calcium. One of these hormones is calcitriol, which tells arterial muscles to contract, increasing blood pressure. It also tells fat cells to “start making fat and sends another message to slow down the process of fat breakdown and oxidation.”
Whatever the mechanism, research seems to conclusively show that calcium is important for weight loss and control and that it is most effective when in dairy form.