Vitamin D Picture Could Be Sunnier For EldersBy
Vitamin D status is better for elderly men and women in the general
population than for elderly hospital patients, according to findings from a
study funded by the National Institutes of Health
and USDA's Agricultural Research Service.
But the study suggests inadequate D is an important public health problem in
Researchers with USDA's Human
Nutrition Research Center on Aging at Tufts in Boston and the
Heart Study conducted the first population-based study of vitamin D with 759
free-living volunteers, age 67 to 95. Epidemiologist Paul Jacques led the
About 15 percent of the women and 6 percent of the men had low blood levels
of 25- hydroxyvitamin D--the major circulating form of vitamin D and the most
sensitive measure of D status. About 4 percent of the women and 2 percent of
the men were deficient.
Vitamin D is essential for healthy bones and teeth and helps prevent
osteoporosis. Milk is fortified with the vitamin, as are some breakfast cereals.
Fatty fish, egg yolks, liver, cheese and butter are naturally rich sources.
Sunlight stimulates skin to manufacture the vitamin. The study data confirm the
importance of eating foods rich in vitamin D and exposing skin to sunlight.
Participants' blood levels of D rose in step with intakes, leveling off only
for men after daily intakes reached 400 International Units--twice the
Recommended Dietary Allowance. Two-thirds of the volunteers drank less than 8
ounces of milk daily, which would supply half the RDA. Vitamin D supplements
were a significant factor for the women's status, but were not as significant
for the men's. Only 25 percent of the women and 20 percent of the men took
vitamin D supplements.
Vitamin D levels were highest in late summer--after months of long, sunny
days--and lowest in late winter. Low D status was inversely associated with
time outdoors. Other study data suggest that older men may have a greater
capacity to make vitamin D than older women.
Scientific contact: Paul F. Jacques, Jean Mayer USDA Human Nutrition
Research Center on Aging at Tufts, Boston, MA 02111, phone (617) 556-3320, fax
(617) 556-3344, firstname.lastname@example.org.