3d illustration of the human brain with visible blood vessels illustrating Alzheimer's disease and dementia, which Biogen is developing treatments for
Credit: Lars Neumann/Getty Images

Researchers at Tufts University in Boston have discovered that patients suffering from cognitive decline with higher levels of vitamin D in their brain have better cognitive function compared to patients with lower levels of the compound.

Dementia affects nearly six million people in the U.S. alone and the numbers are on the rise as the population ages. As of right now, drug development to try and slow down or stop the disease is mostly focused on amyloid plaque buildup or Lewy body disease, with varying success rates.

Taking on a different approach to investigate the illness, a team of researchers at Tufts university has now examined levels of vitamin D in the brain tissue of patients suffering from dementia. Reporting in Alzheimer’s & Dementia, the scientists compared levels of the vitamin in brain tissue of over 200 participants while also assessing their cognitive function.

The study focused on looking for vitamin D in several regions of the brain associated with changes linked to Alzheimer’s disease and dementia such as changes in the blood flow. According to the researchers, the results of the study show that in all examined regions high levels of the compound correlated with better cognitive function.

“Many studies have implicated dietary or nutritional factors in cognitive performance or function in older adults, including many studies of vitamin D, but all of them are based on either dietary intakes or blood measures of vitamin D. We wanted to know if vitamin D is even present in the brain, and if it is, how those concentrations are linked to cognitive decline,” said Kyla Shea, PhD, senior author of the study and associate professor at Tufts University.

According to a previous article, published in Scientific Reports, vitamin D prevented memory deficit in rat models by being able to cross the blood brain barrier and widely distribute itself in the central nervous system with researchers citing chronic deficiency of the vitamin as a potential accelerator of neuronal degeneration.

Despite the positive link to cognitive function, high levels of vitamin D did not associate with any of the other physiological markers usually linked to the disease such as amyloid plaque buildup or evidence of microscopic strokes, making it unclear how exactly the vitamin improves brain function.

“We now know that vitamin D is present in reasonable amounts in human brains, and it seems to be correlated with less decline in cognitive function. But we need to do more research to identify the neuropathology that vitamin D is linked to in the brain before we start designing future interventions,” Shea concluded in a press statement.

Also of Interest