For decades, osteoporosis prevention meant drugs, estrogen, and calcium supplements—all of which we now know are better at increasing bone density than actually reducing hip fractures. Some osteoporosis researchers have taken a different approach: concentrate on ways to prevent elderly people from falling which can, in turn, prevent other injuries as well as hip fractures. This school of thought just got a major boost from the pooled results of eight clinical trials that found high doses of vitamin D3 supplements can cut the chances of falling by up to 26%. Unexpectedly, calcium supplements did not seem to be important to this benefit. Most impressive, the analysis indicates that muscle weakness is reversible in elderly people.
Muscle weakness has long been known to be a key risk factor for falls, and vitamin D is known to improve muscle strength. But there were lingering questions regarding the best type of vitamin D and the appropriate dose for the prevention of falls. They are answered by a new meta-analysis of eight trials, published early this month in the online version of the British Medical Journal. An international team headed by H.A. Bischoff-Ferrari, University of Zurich, Switzerland, identified eight trials in which women and men, age 65 years and older, had been randomly assigned to take either a placebo or some form of vitamin D in doses ranging from 200 to 1,000 International Units (IU) a day, with or without calcium. Trials lasted from 9 to 36 months.
No fall reduction benefit was found in the people who had been taking vitamin D in doses less than 700 IU daily. When the researchers singled out the trials with the highest quality for fall assessment (i.e., five of the eight trials), the best results were shown in the trials that involved high doses of vitamin D3 (cholecalciferol). “38% of individuals treated with 700-1000 IU vitamin D3 had at least one fall versus 50% of individuals in the control group taking calcium or placebo,” explained Dr. Bischoff-Ferrari in an e-mail. This benefit showed up within two to five months of the initiation of treatment.
Dr. Bischoff-Ferrari and colleagues did not rule out the possibility that vitamin D doses higher than 1,000 IU daily could be even more effective. No high-quality randomized trials have explored this possibility. The new findings support the vitamin researchers in the U.S. who, for years, have been calling for an increase in the recommended daily allowance, which is 200 to 600 IU.
And what about that no-effect finding for calcium? This will come as a surprise to older women who have long been told to take at least 1200 mg calcium daily to avoid osteoporosis. Dr. Bischoff explained, “Vitamin D increases the uptake of calcium. If one has more vitamin D, [the] calcium uptake is more efficient and less calcium may be sufficient. That does not mean that we do not need calcium — calcium is important for bone — but it means that when we get sufficient vitamin D, we may lower the recommendations for calcium intake. In clinical practice this may offer the opportunity to recommend vitamin D supplementation in combination with a ‘bone healthy diet’ covering calcium needs by milk products and vegetables rich in calcium. This is possible if the target intake of calcium is 700 mg of calcium per day rather than [current recommendation of] 1000 to 1500 mg per day.” Dr. Bischoff-Ferrari backed up these assertions with two recently published research papers that came with her e-mailed responses.
People fall for a variety of reasons, including over-sedation with prescription drugs. For more about this and the minimal efficacy of Fosamax and other bone drugs, see our 2008 article entitled, “Osteoporosis: many drugs prescribed, not so many hip fractures avoided.” and our 2005 article entitled,”Vitamin D defiency—cause of many ailments.”
Maryann Napoli,Center for Medical Consumers(c)