Calcium-rich diets do not cause excessive weight gain in girls

Nutrition Research Newsletter, Oct, 2004

Optimal calcium intake during childhood and adolescence is necessary for long-term bone health. Close to 98% of peak bone mass has been accrued by the age of 18. Peak bone mass is one of the most important determinants of osteoporotic fracture later in life. Calcium intake is vital in optimizing bone mass accrual. It is known that calcium intake in young girls in the United States is much less than optimal. Dairy foods are the best dietary source of calcium. However, there is some concern that diet high in dairy foods may place individuals at risk for excessive weight gain. Secondary to the increasing incidence of obesity in US children and adolescents, this concern merits consideration.

The purpose of this analysis is to determine whether pubertal girls assigned to calcium-rich diets differ significantly in weight gain from pubertal girls consuming their usual dietary calcium intakes. A convenience sample of 63 healthy 9-year-old girls were recruited and randomly assigned to one of two groups: 1) a treatment group, which was asked to consume calcium-rich foods to supply at least 1,500 mg/day or 2) a control group, which was asked to continue its usual diet. Assessment of usual dietary intake, height, weight, Tanner stage, physical activity, and medical and social history was made on all participants at baseline and every 3 months for the duration of the two-year study. Bone mass and fat and lean body mass were determined semiannually.

The subjects in the calcium-rich diet group had a mean ([ or -] standard deviation) calcium intake, 1,656 [ or -] 191 mg/day, whereas the girls on their usual diets averaged 961 [ or -] 268 mg/day. Although the participants in the treatment group consumed nearly twice as much dietary calcium, primarily from dairy foods, they did not have greater increases in body weight, body mass index, or fat or lean mass than the control group. These findings remained the same when the data were grouped by tertile of calcium intake. Compared with girls on their usual diets, the girls who consumed the calcium-rich diet also significantly increased their intake of essential nutrients.

Calcium-rich diets do not cause weight gain in pubertal girls and likely contribute to improved overall nutrition.

J. Lappe, K. Rafferty, M. Davies, et al. Girls on a high-calcium diet gain weight at the same rate as girls on a normal diet: A pilot study, J Am Diet Assoc; 104: 1361-1367 (September, 2004). [Correspondence: Joan M. Lappe, PhD, RN, Osteoporosis Research Center, Creighton University, 601 N 30th St, Suite 4820, Omaha, NE 68131. E-mail: jmlappe@creighton.edu].