BUFFALO, N.Y. -- Women under the age of 75 with high vitamin D
status were less likely to have early age-related macular
degeneration (AMD), the leading cause of irreversible vision loss
in adults, a University at Buffalo study has shown. The disease
affects approximately 9 percent of Americans aged 40 and older.
The paper is published in the April issue of "Archives of
Ophthalmology," one of the JAMA/Archives journals.
Vitamin D status was assessed using the blood measure of
25-hydroxyvitamin D or 25 (OH) D. The 25 (OH) D level is generally
considered the means by which nutritional vitamin D status is
"In women younger than 75, those who had 25-hydroxyvitamin D
concentrations lower than 38 nanomoles per liter were more likely
to have age-related macular degeneration than women with
concentrations greater than 38 nanomoles per liter," says Amy E.
Millen, PhD, assistant professor in the UB School of Public Health
and Health Professions and lead author. "Blood concentrations above
38 nanomoles per liter were associated with at least a 44 percent
decreased odds of having AMD."
She notes that the Institute of Medicine considers an adult with
a blood 25 hydroxyvitamin D concentration of lower than 30
nanomoles per liter to be at increased risk of vitamin D deficiency
and a person with a concentration of less than 50 nanomoles per
liter to be at increased risk for vitamin D inadequacy.
Millen's "Carotenoids in Age-Related Eye Disease Study (CAREDS)"
involved data from 1,313 women. The purpose of the study was to
investigate if serum 25 hydroxyvitamin D levels in the blood, the
preferred biomarker for vitamin D, were associated with early
age-related macular degeneration. CAREDS is an ancillary study
within the Women's Health Initiative (WHI) Observational Study,
which was conducted at WHI clinic centers in Oregon, Iowa and
Wisconsin. UB is a major participating center in the WHI.
"The take- home message from this study is that having very low
vitamin D status (25-hydroxyvitamin D blood concentrations lower
than 38 nanomoles per liter) may be associated with increasing your
odds of developing age-related macular degeneration," says Millen.
"But based on these study findings, being at a higher vitamin D
level than 38 nanomoles per liter does not appear to be more
protective," she cautions.
Vitamin D status may be increased by spending moderate amounts
of time outside, and eating foods rich in vitamin D, such as fatty
fish from cold waters, and foods fortified with vitamin D, such as
milk and fortified cereal, or by taking supplements.
"This is a promising study, but more still needs to be done,"
says Millen. "We still don't understand all of the effects of
Vitamin D on health."
The research was funded by the NIH and by Research to Prevent
The University at Buffalo is a premier research-intensive
public university, a flagship institution in the State University
of New York system and its largest and most comprehensive campus.
UB's more than 28,000 students pursue their academic interests
through more than 300 undergraduate, graduate and professional
degree programs. Founded in 1846, the University at Buffalo is a
member of the Association of American Universities.