The new study says that earlier supplementation might be particularly beneficial, before the onset of cognitive decline.
Given that the number of people with dementia is growing, it is very important to find ways to stop or even delay its onset.
Recent large-scale research suggests that taking vitamin D supplements may help prevent dementia.
More than 12,388 participants of the US National Alzheimer’s Coordinating Center, who had a mean age of 71 and were free of dementia when they signed up, were examined by researchers at the University of Calgary’s Hotchkiss Brain Institute in Canada and the University of Exeter in the UK to determine the association between vitamin D supplementation and dementia. 37 percent (4,637) of the group used vitamin D pills.
The research, which was published in Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring, revealed that individuals who took vitamin D supplements were more likely to live without dementia for a longer period. Furthermore, the study discovered a 40% decrease in dementia diagnoses among the supplement-taking group.
During the course of ten years, 2,696 persons from the overall sample developed dementia; of these, 2,017 (or 75% of them) had no exposure to vitamin D at any point during their visits before being diagnosed with dementia, while 679 (or 25% of them) had baseline exposure.
According to Professor Zahinoor Ismail, who headed the research team at the University of Calgary and the University of Exeter, vitamin D has some brain-related effects that may help reduce the risk of dementia. However, prior research has produced contradictory findings. He further added that their research provides critical information on which groups could be targeted for vitamin D supplementation.
“Overall, we found evidence to suggest that earlier supplementation might be particularly beneficial, before the onset of cognitive decline.”
Although vitamin D was helpful in both groups, the researchers discovered that females had benefits that were much bigger than those in men. Similarly, individuals with normal cognition saw bigger impacts than those with moderate cognitive impairment, whose changes in cognition are associated with an increased risk of dementia.
Individuals without the APOEe4 gene, which is linked to a higher risk of Alzheimer’s dementia, experienced notably more significant benefits from vitamin D supplementation compared to those with the gene. The authors hypothesized that individuals with the APOEe4 gene might absorb vitamin D more efficiently from their intestines, resulting in a lesser impact from supplementation. However, this hypothesis was not verified by blood tests.
Low vitamin D levels have been associated with an increased risk of dementia, according to prior study. Amyloid, which builds up in the brain and is one of the symptoms of Alzheimer’s disease, is cleared out by vitamin D. Researchers have also shown that vitamin D may prevent tau, another protein linked to dementia, from building up in the brain.
Dr. Byron Creese, a co-author of the study from the University of Exeter, emphasized the importance of preventing or delaying the onset of dementia, especially given its increasing prevalence.
“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 University of Exeter is currently conducting the VitaMIND study, which randomly assigns participants to either a vitamin D or placebo group and examines changes in memory and cognition tests over time to investigate this issue further.
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