Study: Vitamin D supplements may help ward off dementia

By Alice Clifford via SWNS

Researchers have found that vitamin D suppliments can protect against mental decline.

It is available in supplements but is also produced in the body when the skin is exposed to sunlight.

The study looked at two groups – one who didn’t take any vitamin D supplements and one that did.

Out of the supplement-taking group, there were 40 percent fewer dementia diagnoses compared to those who didn’t take any extra vitamin D.

Vitamin D helps get rid of the protein amyloid in the brain, the build-up of which is one of the hallmarks of Alzheimer’s disease.

It also may help protect the brain against a build-up of tau, another protein involved in the development of dementia.

The researchers studied more than 12,388 participants from the US National Alzheimer’s Coordinating Center.

The mean age was 71 and everyone was dementia-free when they signed up. Of the participants, 37 percent took vitamin D supplements.

Across the groups, 2696 people developed dementia over ten years.

Amongst them, 75 percent had no exposure to vitamin D throughout all visits prior to their diagnosis, while 25 percent had been exposed.

While taking vitamin D was effective, the team found that the effects were significantly greater in women than men.

Its impact was also more profound in people with normal cognition, compared to those who reported signs of mild cognitive impairment.

Changes to cognition have previously been linked to a higher risk of dementia.

Professor Zahinoor Ismail, of the University of Calgary and University of Exeter, who led the research, said: “We know that vitamin D has some effects on the brain that could have implications for reducing dementia, however so far, research has yielded conflicting results.

“Our findings give key insights into groups who might be specifically targeted for vitamin D supplementation.

“Overall, we found evidence to suggest that earlier supplementation might be particularly beneficial, before the onset of cognitive decline.”

Vitamin D also had a greater positive impact on those who did not carry the APOEe4 gene.

Carrying this gene is known to present a higher risk for Alzheimer’s dementia.

The researchers suggest that people with the gene absorb vitamin D better from their intestines, possibly reducing the positive effects on the brain.

However, no blood levels were drawn to test this hypothesis.

Co-author Dr. Byron Creese, from the University of Exeter, said: “Preventing dementia or even delaying its onset is vitally important given the growing numbers of people affected.

“The link with vitamin D in this study suggests that taking vitamin D supplements may be beneficial in preventing or delaying dementia, but we now need clinical trials to confirm whether this is really the case.

“The ongoing VitaMIND study at the University of Exeter is exploring this issue further by randomly assigning participants to either take vitamin D or placebo and examining changes in memory and thinking tests over time.”

The study was published in the journal People.