Researchers writing in this week's The Lancet identified 29 randomised trials featuring 63, 897 people over the age of 50, and found that where people were sticking to a prescribed dose of the two, fraction risk was reduced. The combination of vitamin D and calcium has long been recommended to reduce the risk of bone fracture for older people, and this study adds to that ever increasing body of evidence, particularly those at risk of or suffering from osteoporosis, which is estimated to affect about 75m people in Europe, USA and Japan. Use of these supplements is widely accepted by the general public, with calcium reported to be the biggest seller in the US supplements industry. Annual sales were about $993m (€836m) in 2004, according to the Nutrition Business Journal. Just last month a study in the American Journal of Clinical Nutrition found supplementation with calcium and vitamin D could cut bone loss in patients with recent osteoporotic fractures. Osteoporosis is a chronic progressive bone disease, in which bone resorption exceeds bone formation, leading to a reduction in bone-mineral density. Although many studies have investigated the effect of supplementation with calcium or calcium with vitamin D on fracture risk in postmenopausal osteoporosis, there have been "conflicting outcomes," according to Dr Jean-Yves Reginster, from the Bone and Metabolism Unit, Liege, Brussels. Dr Reginster adds in the accompanying comment that Dr Tang "provides clear answers to several questions" thrown up in previous studies. The teams' meta-analysis found that treatment effect in individuals was better with calcium doses of 1200 mg or more, than with doses less than 1200 mg, and with vitamin D doses of 800 IU or more, than with doses less than 800 IU. Lead author Dr Benjamin Tang, from the University of Sydney in Australia, said: "Evidence supports the use of calcium, or calcium in combination with vitamin D supplementation, in the preventive treatment of osteoporosis in people aged 50 years or older. For best therapeutic effect, we recommend minimum doses of 1200 mg of calcium, and 800 IU of vitamin D (for combined calcium plus vitamin D supplementation." The researchers found that supplementation is effective in the preventive treatment of osteoporotic fractures by up to 24 per cent. They added that over an average treatment duration of three to five years, the risk of fracture was reduced and was accompanied by a reduction of bone loss at the hip and spine. The fracture risk reduction was greater in individuals who were elderly, lived in institutions, had a low bodyweight, had a low calcium intake, or were at a high baseline risk than it was in others, they said. The researchers also pointed out that on the basis of their recommended minimum dose of 1200 mg of calcium or 800 IU of vitamin D, many formulations of calcium or combined calcium with vitamin D tablets that are available contain insufficient quantities of the active ingredients They added that adequate dosage in supplements is an important issue to be addressed in relation to good public health, as was the need for individuals to comply with a prescribed level of a set course of time to truly take advantages of these benefits. Dr Tang said: "Poor compliance is a major obstacle to obtaining the full benefit of calcium supplementation." Source: The Lancet Vol 370 August 25, 2007 Use of calcium or calcium in combination with vitamin D supplementation to prevent fractures and bone loss in people aged 50 years and older: a meta-analysis Authors: Benjamin Tang, Guy Eslick, Caryl Nowson, Caroline Smith, Alan Bensoussan.