Too Little Vitamin D May Hasten Mental Decline – WebMD
Too Little Vitamin D May Hasten Mental Decline
By Steven Reinberg
TUESDAY, Sept. 15, 2015 (HealthDay News) — Mental function may decline faster in older adults with low levels of vitamin D, a new study suggests.
“It is unclear what vitamin D might be doing,” said study author Joshua Miller, chair of the department of nutritional sciences at Rutgers University School of Environmental and Biological Sciences in New Brunswick, N.J.
“There is good evidence that vitamin D gets into all cells of the body, including the brain,” Miller said, so it’s possible that vitamin D protects the brain from developing the plaques and tangles that are associated with Alzheimer’s disease.
Unfortunately, “there’s a good chance that most people over 75 in the United States are vitamin D-deficient,” he noted.
Miller cautioned that there’s no proof that taking vitamin D supplements will slow mental decline, as this study only showed an association between the two.
“All we can say is that supplements might be helpful to you,” he said. “And the downside of taking supplements is very small.”
The report was published online Sept. 14 in the journal JAMA Neurology.
The recommended daily intake of vitamin D for older adults is 600 to 800 IU, according to the U.S. National Institutes of Health. Vitamin D, called the sunshine vitamin, is found in fortified foods, such as milk, orange juice, cereals and yogurt. Fish, egg yolks and liver also contain the vitamin.
Miller and his colleagues defined four levels of vitamin D in blood: deficiency as less than 12 nanograms per milliliter (ng/mL); insufficient as 12 to less than 20 ng/mL; adequate as 20 to less than 50 ng/mL; and high as 50 ng/mL or more.
The researchers found that most people in the study had levels of vitamin D that were too low; 26 percent were vitamin D-deficient and 35 percent were vitamin D-insufficient. Blacks and Hispanics had the lowest vitamin D levels, compared with whites.