This is the first major study to show that vitamin D levels predict the risk of falls among such women.
"The solution to vitamin D deficiency may simply be supplying safe and readily available vitamin D supplements," says chief investigator in the study, Professor John Wark.
The study found that 22 percent of hostel residents and a staggering 45 percent of residents in nursing homes suffer from vitamin D deficiency. Vitamin D is synthesized in the skin during sun exposure. It helps to absorb dietary calcium and is vital in forming and maintaining strong bones.
The study was published in the November 2003 issue of the prestigious Journal of the American Geriatrics Society.
"Most of us are able to get our daily requirement for vitamin D from sun exposure plus a small amount from our diets. For elderly people in residential care, this is more problematic as most have impaired mobility, therefore more difficulty getting outdoors," says Professor Wark.
"In addition, the skin of elderly people is less effective at producing vitamin D, further compounding the problem. In Australia, there are few dietary sources for vitamin D, so it is very difficult to make up for the lack of vitamin D production in the skin of people with very restricted sunlight exposure," he says.
"Vitamin D supplements should generally prevent this problem and should be used more widely," he says.
We have known for a long time that adequate vitamin D levels are needed for healthy bones. While other conditions such as impaired cognition and medications are known risk factors for falls, this new study, along with other recent research, indicates that muscle strength and avoidance of falls also require adequate vitamin D stores in the body.