Regular exposure to the sun or taking vitamin D could protect against dementia. This is indicated by the results of a new studywhose authors looked at the connection between the level of this vitamin in middle age and changes in the brain in later years.
They included 793 people with an average age of thirty-nine who did not have dementia at the start of the study. The researchers measured the level of vitamin D in their blood and after about sixteen years they performed a brain examination targeting the proteins tau and amyloid beta, which are related to the development of Alzheimer’s disease.
It turned out that higher levels of vitamin D were associated with lower amounts of the tau protein, which is closely linked to the disease. On the contrary, the association was not demonstrated for beta amyloid.
The most reliable source of vitamin D is the photochemical reaction in the skin. It is enough to spend at least an hour outside every day and UV radiation starts a process in the skin that produces the body’s own vitamin D. This reaction also occurs in cloudy weatheras UV radiation also penetrates through clouds. When the sky is clear, there is more radiation and the production of vitamin D is accelerated, but long-term exposure to the sun can increase the risk of skin cancer. People who cannot regularly spend time outside can use nutritional supplements with vitamin D.
“Our results suggest that higher levels of vitamin D in middle age may provide protection against the formation of tau deposits in the brain. Low levels of vitamin D could be a risk factor that can be manipulated to reduce the risk of dementia.” said study author Martin David Mulligan from the University of Galway.
A higher level was considered more than 30 nanograms per milliliter of blood. About a third of the participants did not reach this value, and only five percent used nutritional supplements regularly.“These findings are promising because they suggest an association between higher vitamin D levels in early middle age and lower tau burden sixteen years later. Middle age is when risk factor modification may have the greatest impact.” dodal Mulligan.
