A new study conducted by researchers from the University of South Australia explored how vitamin D deficiency may impact long-term cognitive health. According to their findings, not having enough of the vitamin may increase the risk of dementia.
“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 researcher Elina Hyppönen. “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 and genetic analyses among a large population.”
Cognitive health risks
For the study, the researchers analyzed data from nearly 295,000 people enrolled in the U.K. Biobank. The team measured their vitamin D levels at the start of the study, then followed them over time to determine how they influenced cognitive health. The researchers also accounted for factors like gender, age, ethnicity, sun exposure, and lifestyle, among several others.
The study showed that lower levels of vitamin D were associated with a higher risk of dementia and stroke. Participants with vitamin D levels under 25 nmol/L were nearly 55% more likely to develop dementia or have a stroke, compared with those whose vitamin D levels were at least 50 nmol/L.
“Most of us are likely to be okay, 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,” Hyppönen said.
The study also showed that boosting vitamin D levels may help prevent poor cognitive health. The researchers learned that increasing vitamin D levels to 50 nmol/L could prevent nearly 20% of dementia cases.
“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 health benefits and we could change the health and well-being for thousands.”