Vitamin D deficiency directly linked to dementia: genetic study
Dementia is a leading cause of disability and dependency in older people worldwide, affecting thinking and behaviors as they age. Around 487,500 Australians live with dementia and it is the second leading cause of death in the country. What if you could stop this degenerative disease in its tracks?
A new study from the University of South Australia could make that a reality, as new genetic research shows a direct link between dementia and a lack of vitamin D.
Investigating the association between vitamin D, neuroimaging characteristics, and the risk of dementia and stroke, the study found:
- Low vitamin D levels were associated with lower brain volumes and an increased risk of dementia and stroke.
- Genetic analyzes have supported a causal effect of vitamin D deficiency and dementia.
- In some populations, up to 17% of dementia cases could be prevented by bringing everyone to normal levels of vitamin D (50 nmol/L).
Supported by the National Health and Medical Research Council, the genetic study analyzed 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 diabetes. ‘stroke.
Nonlinear Mendelian (MR) randomization – a method of using measured variation in genes to examine the causal effect of modifiable exposure on disease – was used to test the underlying causality of neuroimaging findings , dementia and stroke.
Professor Elina Hyppönen, lead researcher and director of UniSA’s Australian Center for Precision Health, said the findings are important for the prevention of dementia and for appreciating the need to abolish vitamin D deficiency.
“Vitamin D is a hormone precursor that is increasingly recognized for its widespread effects, including on brain health, but so far it has been very difficult to examine what would happen if we could prevent vitamin D deficiency,” Hyppönen said.
“Our study is the first to examine the effect of very low levels of vitamin D on the risk of dementia and stroke, using robust genetic analyzes among a large population,” Hyppönen said.
“In some settings, where vitamin D deficiency is relatively common, our findings have important implications for dementia risk. Indeed, in this UK population, we observed that up to 17% of dementia cases could have been prevented by raising vitamin D levels to within a normal range.
“Dementia is a progressive and debilitating disease that can devastate individuals and families,” Hyppönen said.
“If we are able to change this reality by ensuring that none of us are seriously deficient in vitamin D, this would also have other benefits and we could change the health and well-being of thousands of people. .
“Most of us are likely to be fine, but for anyone who, for whatever reason, does not get enough vitamin D from the sun, dietary changes may not be enough and supplementation may be necessary. .”