Vitamin D effects on falls, fracture risk and weight

On April 1, 2007, Internal Medicine News, Endocrinology Section has published an article regarding vitamin D and its effect on falls and fracture risk. In this article it was mentioned that people who take fairly high doses of vitamin D3 or those individuals who already achieved sufficient level of vitamin D in blood serum had significantly reduced risk of certain fractures, falls and decreased bone mineral density. Dr. Cranney and her colleagues extensively reviewed the publications regarding the effects of 25-vitamin D concentrations on the frequency of fractures and falls as well as the decreased mineral density. The results were presented in a conference sponsored by the American Society for Bone and Mineral Research. Statistically it was practically impossible to summarize the results of 31 observational studies and 10 randomized controlled clinical trials in this manner. Therefore, to simplify the assay, Dr. Cranney and her associates categorized the evidence in support of positive effects of vitamin D as inconsistent, fair or good. For serum vitamin D levels of at least 50 to 80 nmol/L there was good evidence of a positive effect on bone mineral density in the hip. At the same time the data showed conclusively that these blood serum concentrations helped reduce the risk of hip fracture.

Looking at 74 randomized, controlled trials of supplementation with D3 and D2, researchers have concluded that vitamin D3 (which is a 25-OH vitamin D) was more efficient than vitamin D2 in preventing falls and fracture and preserving normal mineral density. The amount of vitamin D3 supplementation was at least 700 IU a day. Moreover, 700 IU a day of vitamin D3 was found to decrease serum parathyroid hormone levels. The reviewed studies showed that the reduction in the incidence of various types of fractures was from 15% to 23%, which is statistically significant. Moreover, six clinical trials revealed a significant decrease in the probability of falls in the elderly people.

Another interesting study has been published in the “Archives of Internal Medicine” on May 14, 2007. The study evaluated the risk of post menopausal weight gain when using calcium and vitamin D supplementation. The primary goal of the study was to evaluate the role of calcium in the maintenance of a healthy body weight. The randomized placebo-controlled double blind study was performed with over 36,000 post menopausal females from the age of 50 to 79. The participants were already enrolled in dietary modification and hormonal therapy. Women were randomized to receive a dose of 1000 mg of calcium along with 400 IU of vitamin D versus placebo. The change in body weight was followed on an average of seven years. The participants who were receiving calcium with vitamin D were found to have fairly minimal, but consistent and conclusive favorable difference in weight change. In fact, after three years of follow-up, females who had been receiving calcium with vitamin D supplementation had at least 11% less likely to gain weight. The conclusion of the study was that calcium and vitamin D supplementation had an effect on preventing weight gain which was otherwise observed in women who did not have adequate calcium intake. The study was conducted through the direct supervision of the National Heart, Lung and Blood Institute at Bethesda, Maryland.

The extensive review of these studies have pointed to the conclusion that vitamin D3 supplementation is a safe, cheap and effective measure to decrease the chances of falls and bone fractures in the aging population.