Normal calcium intake during weight loss saves bones - study
high calcium intakes to ward off the threat of osteoporosis,
suggests a new study.
Previous studies have indicated that weight loss can have detrimental effects on bone health later in life, with increased risk of osteoporotic fractures. The new research, published in the new issue of the American Journal of Clinical Nutrition, reports that 44 overweight pre-menopausal women (average age 38, average BMI 27.7 kg per sq. m) on a calorie-restricted diet but consuming normal (1.0 g/day) or high (1.8 g/day) calcium intake did not display any changes to markers of bone turnover or bone health. Osteoporosis is estimated to affect about 75m people in Europe, the USA and Japan. According to the International Osteoporosis Foundation, the total direct cost of osteoporotic fractures is €31.7bn in Europe, and 17.5bn in the US (2002 figure). The total annual cost of osteoporosis in the UK alone is over £1.7bn (€2.5bn), equivalent to £5m (€7.3m) each day. "The present study showed that there is no bone loss with moderate weight reduction in healthy overweight pre-menopausal women at either one gram of calcium per day or 1.8 grams of calcium per day," wrote lead author Claudia Riedt from Rutgers University. "These findings are important because there are numerous studies showing bone loss with weight reduction, but the population is typically older and/or weight loss greater and more rapid," she added. Indeed, the same researchers previously reported that the recommended intake of one gram of calcium per day did not sufficient to prevent bone loss in post-menopausal subjects. While women in this study lost on average 5.5 kg over six months both weight-loss groups maintained the same bone mineral density levels observed at the start of the study. The researchers also note that fractional calcium absorption did decline in all groups over the first six weeks of intervention, the calcium absorption appeared to stay adequate to maintain a calcium balance. "We suggest that overweight pre-menopausal women do not lose bone with moderate weight loss when consuming the recommended intake for calcium," they concluded. This use of the supplements is widely accepted by the general public, with calcium supplements reported to be the biggest seller in the US supplements industry, with annual sales of about $993 (€836) million in 2004, according to the Nutrition Business Journal. Source: American Journal of Clinical Nutrition Volume 85, Pages 972-980 "Premenopausal overweight women do not lose bone during moderate weight loss with adequate or higher calcium intake" Authors: C.S. Riedt, Y. Schlussel, N. von Thun, H. Ambia-Sobhan, T. Stahl, M.P. Field, R.M. Sherrell, S.A. Shapses