A world-first study from the University of South Australia has discovered a direct link between Vitamin D deficiency and dementia.

The Vitamin D and brain health: an observational and Mendelian randomization study published in The American Journal of Clinical Nutrition analysed data from 294,514 participants from the UK Biobank, examining the impact of low levels of vitamin D (25 nmol/L) and the risk of dementia and stroke.

The genetic study, supported by the National Health and Medical Research Council, found that low levels of vitamin D were associated with an increased risk of both dementia and stroke and that in some populations, as much as 17 per cent of dementia cases could be prevented by increasing everyone to normal levels of vitamin D (50 nmol/L).

Senior investigator and Director of UniSA’s Australian Centre for Precision Health, Professor Elina Hyppönen, said the findings are important in preventing dementia and present “important implications for dementia risks”.

“Vitamin D is a hormone precursor that is increasingly recognised 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,” Hyppönen said.

“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.

“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 per cent of dementia cases might have been avoided by boosting vitamin D levels to be within a normal range.”

According to Dementia Australia, in 2022, there are an estimated 487,500 Australians living with dementia.

Dementia encompasses a collection of symptoms that are caused by disorders that impact the brain. Dementia affects thinking, behaviour and the ability to perform everyday tasks.

Across the globe, more than 55 million people have dementia with this number expected to double every 20 years, reaching 78 million in 2030 and 139 million in 2050.

Hyppönen highlighted the significance of the findings given the high number of dementia sufferers around the world.

“Dementia is a progressive and debilitating disease that can devastate individuals and families alike,” Hyppönen said.

“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 wellbeing 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.”

IMPORTANT LEGAL INFO This article is of a general nature and FYI only, because it doesn’t take into account your personal health requirements or existing medical conditions. That means it’s not personalised health advice and shouldn’t be relied upon as if it is. Before making a health-related decision, you should work out if the info is appropriate for your situation and get professional medical advice.