A study involving more than 4,000 healthy adults published in The Lancet has found that taking vitamin D supplements does NOT improve bone mineral density.
The authors conclude that continuing widespread use of these supplements to prevent osteoporosis in healthy adults is in fact needless.
Professor Ian Reid from the University of Auckland in New Zealand explained that most healthy adults do not need vitamin D supplements. The data suggests that the targeting of low-dose vitamin D supplements only to individuals who are likely to be deficient could free up substantial resources that could be better used elsewhere in healthcare.
Osteoporosis causes bones to gradually thin and weaken, leaving them susceptible to fractures. About 2 million fractures occur each year due to osteoporosis.
Bone mineral density is a measure of bone strength and measures the amount of bone mineral present at different sites.
This measurement was taken at one of five sites – lumbar spine, femoral neck (neck of the femur or thigh bone), total hip, trochanter (part of the femur), total body or forearm. Because the trochanter is a major component of the total hip, the findings for this area were included with the hip.
Analysis of data from 23 studies involving 4,082 healthy adults (with an average age of 59) did not identify any effects for people who took vitamin D for an average period of 2 years, apart from a small but statistically significant increase in bone density (0.8%) at the femoral neck.
According to the authors, such a localized effect is unlikely to be clinically significant.
The authors conclude:
“This systematic review provides very little evidence of an overall benefit of vitamin D supplementation on bone density. Continuing widespread use of vitamin D for osteoporosis prevention in community-dwelling adults without specific risk factors for vitamin D deficiency seems to be inappropriate.”
Writing in a linked comment in The Lancet, Clifford J. Rosen from the Maine Medical Research Institute discusses how our recent understanding of vitamin D lends support to these findings.
He points out that for people with normal bones and an adequate calcium intake, there is little or no need for vitamin D supplementation.
“Supplementation to prevent osteoporosis in healthy adults is not warranted. However, maintenance of vitamin D stores in the elderly combined with sufficient dietary calcium intake (800-1200 mg per day) remains an effective approach for prevention of hip fractures.”
Dr. Anbarrasu N.D.