Higher Vitamin D, Better Golden Years?
Older Adults With Higher Vitamin D Levels Have Improved Mobility, Study Finds
April 26, 2010 (Anaheim, Calif.) -- Vitamin D, already considered a way to
help fight colds, cancer, diabetes, heart disease, and other ills, may also
keep people mobile in their golden years, according to a new study.
Older adults who had higher blood levels of vitamin D had better physical
functioning, says Denise Houston, PhD, RD, assistant professor of internal
medicine at Wake Forest University in Winston-Salem, N.C. She presented the
findings Sunday at the Experimental Biology 2010 meeting.
"Those with better vitamin D levels started out better and ended up better
on physical performance tests," she tells WebMD.
Vitamin D in Older Adults: Study Details
Results have been mixed in previous studies looking at whether vitamin D
helps physical functioning in older adults, Houston says. Some studies found no
effect of boosting low vitamin D levels in seniors and other studies showed an
Vitamin D, important for promoting calcium absorption, maintaining muscle
strength, promoting bone growth and repair, and other activities, is produced
when ultraviolet rays from the sun strike the skin and spark its synthesis.
It's found naturally in few foods and is added to others. Deficiency is
common, especially with age, because the ability to synthesize vitamin D
declines. Older adults also have difficulty converting vitamin D to its active
In the new study, researchers wanted to see if vitamin D could delay
age-related changes in physical functioning.
So Houston and her colleagues evaluated 2,641 older men and women, on
average age 75.
The older adults were part of the Health, Aging, and Body Composition
(Health ABC) Study that looked at the links between body composition, health
conditions, and mobility with age.
For this new analysis, Houston divided the adults into three groups,
depending on whether their vitamin D levels as evaluated from blood samples was
low, medium, or high.
Those terms were relative, she tells WebMD, as ''two-thirds had vitamin D
For the study, low blood levels of vitamin D were under 50 nanomoles per
liter (nmol/L), high blood levels were those 75 or higher, and levels of 50-75
All the adults were tested to assess physical function, including walking
400 meters (about 1/4 mile) as fast as possible, standing from a chair without
using the arms, balance tasks, and other tests of their lower extremity
strength and functioning.
The tests were given at the start of the study and repeated two and four