Everyone knows that vitamin D is vital for healthy bones and a stronger immune system but could low levels also be a major driver of Alzheimer’s and age-related cognitive decline?
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New research suggests they could, and that levels of vitamin D commonly found in the UK are accelerating cognitive decline and increasing the risk of a dementia diagnosis (1). Supplementing vitamin D, especially in the winter, may reduce future dementia risk.
And it’s not just the UK. A study in France showed that those with low vitamin D levels, below 50nmol/l, had a nearly three-fold increased risk of Alzheimer’s (2). In the UK, over 60 percent of people aged 11 and over have lower levels than this (3).
Supplements also help ward off dementia, according to a large-scale study earlier this year involving over 12,000 dementia-free 70+ year olds (4). More than a third (37%) took supplements of vitamin D and had a 40% lower incidence 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 in the brain that could have implications for reducing dementia, however so far, research has yielded conflicting results. Overall, we found evidence to suggest that earlier supplementation might be particularly beneficial, before the onset of cognitive decline.”
Did you know we just launched our at-home vitamin D blood tests and MIND Vitamin D Research Project? Will you join our research project and test and track your own vitamin D with us?
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Vitamin D expert and Director of the Sunlight, Nutrition and Health Research Center in San Francisco and a member of our Scientific Advisory Board, Dr William Grant, says we’ve vastly under-estimated the importance of vitamin D on the brain and how much you need.
“All the evidence for bone and immune health shows that you need a blood level of vitamin D above 75nmol/l to be healthy, and the same is proving true for the brain. This optimal level is impossible to achieve without supplementation in the winter. I recommend every adult and teenager supplement 3,000iu a day from October to March. The government’s recommendation of 400iu (10mcg) is not enough for optimal brain health. Supplementing 800iu (20mcg) a day for 12 months has already been shown to improve cognitive function but you need more than this to achieve anything close to an optimal level.” says Dr Grant. “If you’re not supplementing vitamin D in the winter they are heading for cognitive decline.” Yet only eight percent of UK adults take vitamin D in the winter, says the British Nutrition Foundation (6).
Under the direction of Dr Grant, we have launched a research project to test both vitamin D levels, using a home test kit, and cognitive function, with a free online Cognitive Function Test.
“We have tested over 400,000 people’s cognitive function and now we want to discover their vitamin D levels. This will establish how much vitamin D you really need to stay free from dementia” says Dr Grant.
If you’d like to take part in this research and discover your vitamin D level and cognitive function click here . The free online Cognitive Function test also works out what’s driving future dementia risk and tells you what to do about it
Did you know we just launched our at-home vitamin D blood tests and MIND Vitamin D Research Project? Will you join our research project and test and track your own vitamin D with us?
Thank you for reading!
Food for the Brain is a non-for-profit educational and research charity that offers a free Cognitive Function Test and assesses your Dementia Risk Index to be able to advise you on how to dementia-proof your diet and lifestyle.
By completing the Cognitive Function Test you are joining our grassroots research initiative to find out what really works for preventing cognitive decline. We share our ongoing research results with you to help you make brain-friendly choices.
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2 Jia J et al. Effects of vitamin D supplementation on cognitive function and blood Aβ-related
biomarkers in older adults with Alzheimer’s disease: a randomised, double-blind, placebo-
controlled trial. J Neurol Neurosurg Psychiatry. 2019 Dec;90(12):1347-1352. doi:
10.1136/jnnp-2018-320199. Epub 2019 Jul 11. PMID: 31296588.
3 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7353432/pdf/nutrients-12-01868.pdf
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doi: 10.1002/dad2.12404. PMID: 36874594; PMCID: PMC9976297.
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36771403; PMCID: PMC9920487.
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10.3390/nu13020499. PMID: 33546262; PMCID: PMC7913332.
7 Engelsen O. The relationship between ultraviolet radiation exposure and vitamin D status.
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8 Ekwaru JP et al The importance of body weight for the dose response relationship of oral
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9 Feart C et al.. Associations of lower vitamin D concentrations with cognitive decline and
long-term risk of dementia and Alzheimer’s disease in older adults. Alzheimers Dement.
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10 https://apigateway.agilitypr.com/distributions/history/4db5dd81-e4c6-4503-b961-
ca44baed4423
