Summary: Researchers have found a link between vitamin D deficiency and decreased brain size. Low vitamin D is also associated with the risk of stroke and mental disorders. Up to 17% of dementia can be prevented by increasing vitamin D.
A source: University of South Australia
Dementia is one of the leading causes of disability and addiction in older people around the world, affecting their thinking and behavior as they age. But what if you could stop this degenerative disease on its own?
The world’s first study by the University of South Australia could make this a reality, as new genetic research has shown a direct link between dementia and vitamin D deficiency.
In a study of the relationship between vitamin D, neuroimaging features, and the risk of dementia and stroke, the study found:
- Low levels of vitamin D are associated with decreased brain volume and the risk of dementia and stroke
- Genetic analysis has supported the causal effects of vitamin D deficiency and dementia.
- In some populations, up to 17 percent of cases of dementia can be prevented by increasing the normal level of vitamin D in each person (50 nmol / l).
Dementia is a chronic or progressive syndrome that leads to impaired cognitive function. Approximately 487,500 Australians live with dementia, the second leading cause of death in the country. More than 55 million people worldwide suffer from dementia, and 10 million new cases are diagnosed each year.
The genetic study, supported by the National Council for Health and Medical Research, analyzed data from 294,514 participants from the UK Biobank to study the effects of low levels of vitamin D (25 nmol / l) and the risk of dementia and stroke. Nonlinear Mendelian randomization (MR), a method of measuring measured variation in genes to study the causal effects of altered exposure to disease, has been used to examine the underlying causes of neurovisual outcomes, dementia, and stroke.
Professor Elina Gipponen, senior investigator and director of the Australian Center for Accurate Health at UniSA, said the research was important to assess the need to prevent dementia and address vitamin D deficiency.
“Vitamin D is a common precursor hormone, including one known for its effects on brain health, but so far it has been difficult to study what would happen if we could predict vitamin D deficiency,” says Professor Gipponen.
“Our study is the first to study the effects of very low levels of vitamin D on the risk of dementia and stroke, using strong genetic analysis among the general population.
“In some contexts, vitamin D deficiency is relatively common, and our findings have important implications for the risk of dementia. Indeed, in this UK population, we have found that up to 17 percent of dementia can be prevented by raising vitamin D levels in the normal range.”
Given the prevalence of dementia around the world, the findings are remarkably significant.
“Dementia is a progressive and debilitating disease that can destroy both individuals and families,” says Professor Gipponen.
“If we can change this fact, if none of us are deficient in vitamin D, it will have another benefit and we can change the health and well-being of thousands of people.”
“Most of us are in good condition, but for someone who for some reason can’t get enough vitamin D from the sun, changing their diet may not be enough and they may need extra food.”
News about vitamin D and dementia research
Author: Annabel Mansfield
A source: University of South Australia
The connection: Annabel Mansfield is a University of South Australia
Photo: Image in public domain
Original study: Open access.
“Vitamin D and Brain Health: Observation and Mendel’s Randomization Study” by Elina Hyppönen et al. American Journal of ClinicalNutrition
Vitamin D and brain health: an observational and Mendel randomization study
High vitamin D status is said to have beneficial effects on the brain.
Study of the relationship between 25-hydroxyvitamin D. [25(OH)D]Features of neuroimaging and the risk of dementia and stroke.
We used prospective data from the British Biobank (37-73 and primary) to investigate the association of 25 (OH) D concentrations with neuroimaging results.Do not = 33,523) and risk of dementia and stroke (Do not = 427,690; 3414 and 5339 cases). Observations were tailored to age, sex, ethnicity, month, center, and socioeconomic, lifestyle, solar behavior, and disease-related factors. Nonlinear Mendel randomization (MR) assays were used to examine the underlying causality of neuroimaging results (Do not = 23,901) and dementia and stroke (Do not = 294,514; 2399 and 3760 cases).
Compounds between 25 (OH) D and total, gray matter, white matter, and hippocampal volumes are nonlinear, with even lower volumes for lower and higher concentrations (corrected). P-Nonlinear ≤ 0.04). 25 (OH) D was inversely related to the hyperintensive volume of white matter [per 10 nmol/L 25(OH)D; adjusted β: –6.1; 95% CI: –11.5, –7.0]. Vitamin D deficiency is associated with the strongest compounds, dementia, and stroke risk for those with 25 (OH) D <25 nmol / l (compared to 50–75.9 nmol / l; adjusted HR: 1.79; 95% CI) . 1.57, 2.04 and HR: 1.40; 95% CI: 1.26, 1.56).
Nonlinear MR analyzes confirmed the effect of 25 (OH) D on the threshold for dementia, with a risk of 25 nmol / l compared to 50 nmol / l for participants with 54% (95% CI: 1.21, 1.96). 25 (OH) D was not associated with neuroimaging results or stroke risk in MR assays. The potential exposure fraction suggests that dementia can be prevented by increasing the 17% (95% CI: 7.22, 30.58) 25 (OH) D to 50 nmol / l.
Low vitamin D status is associated with the risk of dementia and stroke even after neuroimaging results and extensive covariance adjustment. MR assays support the causal effect of vitamin D deficiency on dementia rather than the risk of stroke.