August 23, 2006
Low Vitamin D Linked to Seniors’ Risk of Falling
By Amy Norton
NEW YORK (Reuters Health) - Older men and women with vitamin D deficiency are more likely to fall multiple times in the course of a year than their peers with adequate vitamin D levels, researchers in The Netherlands have found.
Vitamin D may be best known for its role, along with calcium, in maintaining bone health. However, vitamin D is also important for muscle mass and strength, and compromised muscle function may explain the fall risk seen in this study, according to the researchers.
The findings suggest that older adults should be sure to get adequate vitamin D from food and multivitamins, lead study author Dr. Marieke B. Snijder, of Vrije Universiteit Amsterdam, told Reuters Health.
However, she added, clinical trials are needed to prove that this actually prevents falls.
Snijder and her colleagues report their findings in the Journal of Clinical Endocrinology & Metabolism.
For their study, the researchers measured blood levels of vitamin D in 1,231 adults age 65 and older, then followed them for one year to track any falls they suffered. During that time, 33 percent fell at least once, according to "fall calendars" that each participant kept. Just over 11 percent fell two or more times.
Overall, men and women who were deficient in vitamin D at the outset were 78 percent more likely than those with adequate levels to fall at least twice. Their risk of falling three or more times was more than doubled.
Other fall risk factors, such as exercise, smoking and drinking habits, did not explain the link. However, at the start of the study, participants with vitamin D deficiency did perform more poorly on tests of physical function, including walking and getting up and down from a chair.
According to Snijder, this suggests that a lack of vitamin D may weaken and impair older adults' muscles.
The body produces its own vitamin D store when sunlight triggers its synthesis in the skin. However, lack of sun exposure, less efficient vitamin D synthesis and inadequate dietary intake all conspire to make deficiency common among older adults, Snijder said.
In one Dutch study, she noted, up to two-thirds of elderly adults were at least moderately deficient in vitamin D.
Dietary sources of the vitamin are relatively few and include fortified milk and breakfast cereals, and certain fish, like salmon, tuna and sardines. Older adults may need a multivitamin to get the recommended amount of vitamin D.
SOURCE: Journal of Clinical Endocrinology & Metabolism, August 2006.