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Does the sun prevent Dementia?

Can you avoid Alzheimer’s by sunbathing? Sounds tempting. Actually, research suggests a connection between the vitamin D supply in our body and dementia. Reality, though, is much more complex with many speculations.

There is no question about it: the sun is known to be the most important natural source needed so the body can produce vitamin D. And we have known for a long time about the positive influences on good bone health produced by vitamin D, which is actually not a vitamin but instead a hormone. Vitamin D docks up to receptors on bones which act as a switch in the cells activating and controlling numerous genes. 

Other organs also absorb vitamin D and use it for cell metabolism. Research results suggest that the importance of this “sun hormone” for health and well-being is greater than previously thought. Currently, though, these assumptions from doctors and scientists are mainly based on observations of numerous studies worldwide.

For example, doctors at Johns Hopkins University in Baltimore suspect that people with vitamin D deficiency have a 26 percent increased risk of dying from a heart attack. The risk of diseases such as multiple sclerosis and Parkinson's could also increase. Yet, we are still missing clear facts and scientific evidence for conclusive results. Most research concludes that further research and investigation is necessary and/or advisable. Larger sample studies are needed over longer periods of time in order to draw definitive conclusions.

There is hope, but no scientific evidence yet

Recent studies have also shown a connection between the amount of vitamin D in the body and dementia. Vitamin D deficiency is common in elderly. This is because older people are less likely to be outside, especially in industrialized countries. Dementia could be one possible consequence. A long-term study by the University of Exeter with 1,658 Americans came to this conclusion.

Participants were examined again after six years checking the vitamin D level in their blood both times. People with very severe vitamin D deficiency were more than twice as likely to develop dementia. Researchers found that participants who had a slight deficiency, still had a 53 percent higher risk.

When the sun gets under your skin

Vitamin D plays an important role in some of our articles on our sun care website. The reason is quite simple: Vitamin D production is closely connected to the sun and has been proven to be very important for different processes in the human body.

Read more

This is only a statistical correlation and there is no evidence yet of a causal relationship. We don’t exactly know how vitamin D deficiency could damage the brain’s memory centers. Researchers suspect that brain cells also have vitamin D receptors. And there is a certain enzyme required for the production of the bioactive form of the vitamin that is distributed in the brain. Just like macrophages, which behave like garbage disposals in cells, the enzymes remove and recycle deposits and leftover cell metabolism.

Can dementia be prevented by taking regular vitamin D supplements or spending time in the sun? Probably not. Research doesn’t confirm this hope, even though it seems Alzheimer’s and dementia can be triggered by having a “sun hormone” deficiency. 

However, it has been proven that there is a clear connection between dementia and vitamin D deficiency. This sun hormone probably can’t prevent the disease, but it looks like it can slow its course.

Vitamin D science is still at an early stage. There is evidence that it can do more than “just” take care of bones. There is hope with some diseases, that vitamin D can have a positive effect on disease progression. Yet, it is also very clear that as long as there is no scientific evidence and compelling answers, don’t get your hopes up for this miracle hormone. That doesn’t change, though, one finding in the current state of science: vitamin D is important.