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Lacking This Vitamin Can Lead to Dementia, Says New Study

Your brain needs healthy habits too.
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You know the healthy habits you need to adopt to protect your heart, but were you aware certain lifestyle changes can keep your brain healthy, reducing your risk of age-related disorders like dementia? They include diet, exercise, and according to a new study, making sure you're getting enough of this vitamin on a daily basis. Read on to find out more—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


What The Study Found

vitamin d in the sun

According to a new study published in the Journal of Clinical Nutrition, having a low vitamin D level is associated with smaller brain volume and an increased risk of dementia and stroke, and almost 20 percent of dementia cases could be prevented by keeping vitamin D level in a healthy range.


How the Study Was Conducted

Doctor examines MRI scan of head, neck and brain of patient

Researchers from the University of Australia analyzed health data from more than 290,000 people in the UK Biobank, comparing vitamin D levels with brain imaging that measured the size of gray matter, white matter, and the hippocampus, the part of the brain responsible for executive functions like memory.

The scientists found that participants who had a genetically higher level of vitamin D had a decreased dementia risk, with the odds of dementia decreasing with higher concentrations of the vitamin, up to 50 nmol/L, after which the benefits were less marked.


Vitamin D's Benefits Widely Recognized

happy woman stretching arms in sunshine

Scientists have long known about vitamin D's importance to overall health, including the immune system and bones. But less research has been done on the vitamin's effect on the brain.

"Vitamin D is a hormone precursor that is increasingly recognized for widespread effects, including on brain health, but until now it has been very difficult to examine what would happen if we were able to prevent vitamin D deficiency," said Elina Hyppönen, the study's lead author. "Our study is the first to examine the effect of very low levels of vitamin D on the risks of dementia and stroke, using robust genetic analyses among a large population."

She added: "In some contexts, where vitamin D deficiency is relatively common, our findings have important implications for dementia risks. Indeed, in this UK population, we observed that up to 17 percent of dementia cases might have been avoided by boosting vitamin D levels to be within a normal range."


Low Levels of Vitamin D Common


Both low levels of vitamin D and dementia are not uncommon in the U.S. It's estimated that 40% of Americans have insufficient levels of the vitamin. And about 5.8 million Americans suffer from Alzheimer's disease and dementia-related conditions, a number that's expected to increase as the population ages. 

"Dementia is a progressive and debilitating disease that can devastate individuals and families alike," said Hyppönen. "If we're able to change this reality through ensuring that none of us is severely vitamin D deficient, it would also have further benefits and we could change the health and well-being for thousands."

"Most of us are likely to be OK, but for anyone who for whatever reason may not receive enough vitamin D from the sun, modifications to diet may not be enough, and supplementation may well be needed."


What to Do About Your Vitamin D Level

Scientist examining a test-tube in a laboratory

It's a good idea to get your vitamin D level checked by your doctor annually. If your levels are low, they might recommend a supplement. According to the National Institutes of Health, adults are advised to get at least 600 IU of vitamin D each day, between food and supplements (although that number is somewhat controversial, and some doctors believe it should be higher). The NIH notes that the safe upper limit of vitamin D for adults is 4,000 IU a day.

And to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.

Michael Martin
Michael Martin is a New York City-based writer and editor. Read more about Michael