Dr. Rhonda Patrick

So these kind of show up as little white hyper spots, if you're looking at an MRI image of the brain, and it's really a marker of damage to the white matter in the brain.

And the white matter is where

is it's so important for brain function, for communication.

It's how your brain's communicating.

So when you have damage to that white matter, it really does affect cognition.

It affects communication and memory.

For every 10 nanomole per liter increase in vitamin D, there was a small decrease in the volume of these white matter hyperintensities, suggesting that having higher levels of vitamin D can protect against this type of brain damage.

Even a step further, looking at vitamin D supplementation and how that can affect cognition.

Now, there's a lot of mixed data out there, particularly when it comes to vitamin D supplementation affecting cognition in normal, healthy adults, but there have been a few trials that have actually looked at vitamin D supplementation in people with either Alzheimer's disease or people with mild cognitive impairment.

So in both those scenarios, in people with mild cognitive impairment, if they took around 800 IUs of vitamin D daily for a year, they had significant improvements in multiple areas of cognition, memory, attention, overall IQ.

And the same goes with the Alzheimer's disease study.

So people that took, again, 800 IUs a day for over a year, and these people were already diagnosed with Alzheimer's disease, they also had improved scores on memory and attention tests, similar to that first trial I just mentioned.

But additionally, there was also a reduction in blood biomarkers of amyloid beta pathology, such as amyloid beta-42, which is associated with Alzheimer's disease progression.

So this data really strengthens the argument that low vitamin D can increase dementia risk and that supplementing with vitamin D can help lower that risk, which brings us back to this recent study where vitamin D supplementation was associated with a 40% lower risk of dementia.

So let's dive into that a little bit closer.

So the study included 12,388 adults who were divided into two groups, those who reported using vitamin D supplements in any form.

It could be calcium vitamin D. It could be the active form of vitamin D. It could be vitamin D2.

So any form of vitamin D, it didn't matter what form.

And then the other group it was divided into is those that did not take any form of vitamin D supplement.

There was a 10-year follow-up, and during that period, supplementing with vitamin D was associated with a 40% lower incidence of dementia.