Older people who are Vitamin D deficient are at a substantially increased risk of developing dementia, a study in the journal Neurology has found.
About five million adults in the U.S. suffer from Alzheimer's, with approximately 500,000 of them dying from the disease each year, according to the Alzheimer's Association.
Lead researchers were surprised by the result, finding the link stronger than they anticipated. Study author David J. Llewellyn commented on the findings. "We expected to find an association between low Vitamin D levels and the risk of dementia and Alzheimer's disease, but the results were surprising-we actually found that the association was twice as strong as we anticipated."
The study evaluated vitamin D levels in 1,658 healthy people age 65 and older without dementia. Six years later, 171 persons in the study developed dementia and 102 had Alzheimer's disease.
The results were unchanged after researchers adjusted for factors that could affect risk of dementia, such as smoking, alcohol use, as well as education.
The findings of the study are published in the online issue of Neurology, the medical journal of the American Academy of Neurology.
