Vitamin D deficiency may cause dementia, scientists find

Credit: CC0 Public Domain.

In a study from the University of South Australia, scientists found a direct link between dementia and vitamin D deficiency.

Vitamin D is a nutrient you need for good health. It helps your body absorb calcium, one of the main building blocks for strong bones.

Together with calcium, vitamin D helps protect you from developing osteoporosis, a disease that thins and weakens the bones and makes them more likely to break.

Your body needs vitamin D for other functions too. Your muscles need it to move, and your nerves need it to carry messages between your brain and your body.

Your immune system needs vitamin D to fight off invading bacteria and viruses. Higher vitamin D status has been suggested to have beneficial effects on the brain.

Very few foods naturally contain vitamin D. Fortified foods provide most of the vitamin D in the diets of people in the United States.

Dementia is the loss of cognitive functioning — thinking, remembering, and reasoning — to such an extent that it interferes with a person’s daily life and activities.

Some people with dementia cannot control their emotions, and their personalities may change.

A stroke, also known as a transient ischemic attack or cerebrovascular accident, happens when blood flow to the brain is blocked. This prevents the brain from getting oxygen and nutrients from the blood.

Without oxygen and nutrients, brain cells begin to die within minutes. Sudden bleeding in the brain can also cause a stroke if it damages brain cells.

In the current study, researchers aimed to examine the link between vitamin D levels in the body and the risks of dementia and stroke.

They used data from people who were 37-73 years old before the study to examine the association between vitamin D levels with brain imaging outcomes and the risk of dementia and stroke.

The researchers found vitamin D levels in the brain were linked to brain imaging results.

More importantly, vitamin D deficiency was linked to an increased risk of dementia and stroke, with the strongest associations for those with 25(OH)D <25 nmol/L.

The team also found that the people whose vitamin D level was 25 nmol/L had a 54% higher risk of dementia compared with people whose vitamin D level was 50 nmol/L.

Further analysis showed that 17% of dementia could be prevented by increasing vitamin D levels to 50 nmol/L.

The team also found that vitamin D level was not linked to stroke risk.

Based on these findings, the researchers concluded that low vitamin D status was linked to brain imaging outcomes and the risks of dementia.

There is a causal effect of vitamin D deficiency on dementia but not on stroke risk.

The research is published in The American Journal of Clinical Nutrition and was conducted by Professor Elina Hyppönen et al.

Copyright © 2022 Scientific Diet. All rights reserved.