Vitamin D Deficiency Boosts Dementia Risk in Older Adults
Alzheimer's disease, which is the most common type of dementia, affects more than five million people in American according to the Alzheimer's Association. There is no cure for the disease, but researchers have been studying risk factors with the hopes of delaying or preventing its onset. In a new study, researchers found that older people who have low vitamin D levels have a greater risk of developing Alzheimer's.
"It is too early to tell whether improving vitamin D levels helps to delay or prevent dementia - clinical trials are now urgently needed," said senior author David J. Llewellyn of the University of Exeter Medical School in the U.K reported by Reuters.
In this study, the researchers examined 1,658 men and women who were a part of the U.S. Cardiovascular Health Study, which took place from 1992 to 1993 and once more in 1999. The participants were all over the age of 65. The study collected blood samples and assessed the participants' mental health status. 419 people were deficient in vitamin D and 70 people were severely deficient. By 1999, 171 participants were diagnosed with dementia with 102 of them being Alzheimer's.
The researchers discovered that during the follow-up, adults who had slightly low vitamin D levels in their blood were around 1.7 times more likely to develop Alzheimer's in comparison to adults who had normal levels of vitamin D. People with extremely low levels of vitamin D were 2.2 times more likely to develop dementia in comparison to people with normal levels.
"What's important about this study is the large number of participants," Keith Fargo, director of scientific programs and outreach for the Alzheimer's Association, said according to Philly. "This shows you there is a link between vitamin D and the development of Alzheimer's. What it doesn't show you is that [cause-and-effect] link. We don't know if increasing vitamin D levels would decrease the risk of Alzheimer's."
The study, "Vitamin D and the risk of dementia and Alzheimer disease," was published in the journal, Neurology.