New trial to probe calcium's role in weight, bone loss
are undertaking the largest and longest clinical trial to study the
effects of calcium in postmenopausal women.
“There is a lot of controversy regarding the role of Ca and/or dairy products in weight/body composition. This study, being the largest and longest lasting, has a potential to clarify the issue of the role of Ca as well as the dairy products in weight reduction/maintenance,” lead researcher, Professor Jasminka Ilich told NutraIngredients-USA.com. Ilich predicts the project, funded by an $840,000 grant from the US Department of Agriculture, will become the definitive investigation of calcium’s role in post-menopausal women, and should shed light on calcium’s role at a cellular level. The debate about whether calcium or dairy foods can promote weight loss is ongoing with research appearing to support both sides of the argument. A study from Purdue University, for example, claimed that young women could burn more calories if they ate three or four dairy servings per day. However another report, also from Purdue, reported that increased dairy consumption had no effect on weight gain or loss. Professor Ilich’s study will also examine the possibility of preserving bone loss, usually occurring with the weight loss. The combination of vitamin D and calcium has long been recommended to reduce the risk of bone fracture for older people, particularly those at risk or suffering from osteoporosis, estimated to affect about 75 million people in Europe, the USA and Japan. 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. The intervention study by the Florida State researchers will randomly assign post-menopausal, overweight or obese women to one of three groups for one year. One group will consume low-fat dairy products, the second group will receive a calcium supplement (1500 mg per day), and the third group a placebo. San Antonio-based Mission Pharmacal will supply the calcium plus vitamin D (Citracal) and placebo. “While my previous studies show that calcium could be something of a magic bullet, seemingly supporting bone strength, weight maintenance and better body composition, this research will take a closer, longer look at a larger sampling of a specific group,” said Ilich. The Florida State researchers's labs are equipped with the latest in whole-body scanners with dual-energy X-ray absorptiometry. “iDXA (or intelligent DXA) is the newest in the bone densitometry technology. It measures both bone and body composition (fat and lean tissue) with higher precision, accuracy and speed than any of the previous DXA models. And even more, it can accommodate heavier patients (up to 400 lbs) and measure their bone and body composition accurately, which was not the case with the previous models,” she said. Volunteers will undergo scans at six-month intervals to measure initial body composition and any subsequent changes. Calcium alone or with vitamin D has been receiving steady attention. Potential benefits from the mineral have not been limited to bone health, but also colorectal cancer and other diseases. A selection of other ongoing clinical trials are listed below. Trial Phase Trial Name Intervention Condition Date of completion III Supplemental calcium in overweight people NCT00030238 calcium supplement (1500mg per day ) Overweight Ongoing follow-up II and III Vitamin D/Calcium Polyp Prevention Study NCT00153816 Calcium carbonate (1200mg) Vitamin D3 (1000IU) Colorectal Cancer Polyps Adenomas January 2014 II Adding Phosphorus to Osteoporosis Drug Treatment NCT00074711 Calcium carbonate Calcium phosphate Vitamin D Osteoporosis August 2007 I Effect of Vitamin D and Calcium on Genes in the Colon NCT00298545 Calcium Vitamin D Colorectal Polyps Adenomas January 2007 I Bone Mineral Density, Body Composition and Growth Following Severe Burn Injury NCT00285090 Calcium Vitamin D Burn Growth Malnutrition January 2011