- Andrew Grey, associate professor 1,
- Mark Bolland, associate professor1
- 1Department of Medicine, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Correspondence to: A Grey
- Accepted 1 April 2015
For many years, recommendations for prevention and treatment of osteoporosis have included increasing calcium intake (by diet or supplements) and use of vitamin D supplements. Since the average dietary calcium intake in most countries is much less than that recommended by guidelines (table 1⇓), many older people are advised to take calcium supplements to prevent osteoporosis. The recommendations have been implemented successfully: over half of older Americans take calcium and vitamin D supplements, either prescribed or over the counter, and bone health is the most common specific motivation for use of nutritional supplements.1 2 However, this behaviour does not reflect evidence that has emerged since 2002 that such supplements do not reduce the risk of fracture and may result in harm. Guideline bodies also continue to recommend calcium and vitamin D supplements. Here, we argue that change is made difficult by a complex web of interactions between industry, advocacy organisations, and academia.
Evidence on calcium and vitamin D
The first consensus statement on osteoporosis in 1984 recommended a daily calcium intake of 1500 mg in postmenopausal women, based on short term whole body calcium balance studies.3 4 Later, use of vitamin D supplements in older adults was recommended by an osteoporosis consensus development panel based on extrapolation from a trial conducted in frail, very elderly, institutionalised women to the general population.5 6 Enthusiasm for calcium and vitamin D supplementation was fuelled by a small randomised trial that reported a reduced incidence of …