Study Shows This Vitamin May Lower Your Risk Of Alzheimer’s By 17%

While vitamin D is most known for its role in bone health, there are vitamin D receptors throughout the body—including the brain. And there’s no shortage of research showing that vitamin D plays a role in memory and even mood.

But scientists are now trying to hone in on just how much vitamin D status influences the risk of cognitive conditions like Alzheimer’s disease. 

In this study, researchers followed a large group of people over 14 years to see how their vitamin D status, vitamin D supplementation, and multivitamin use influenced the onset of an Alzheimer’s disease of vascular dementia1 diagnosis. 

Here’s what you need to know. 

About the study

Studying the incidence of an Alzheimer’s diagnosis is no easy feat. There are a lot of factors to consider, and researchers of this study did their due diligence. 

They were able to gather data on almost 270,000 adults (ages 55 to 69 at the start of the study) including their use of supplements (vitamin D or multis), blood levels of vitamin D, and dementia status around 14 years later. 

At the start of the study: 

Researchers also accounted for other factors that influence dementia risk including demographic characteristics, socioeconomic status, lifestyle habits, and genetic factors including the APOE4 genetic variation.

By considering these factors, they could more accurately isolate the vitamin D and dementia relationship. 

The link between vitamin D and dementia

At the end of the study, researchers found:

One interesting finding the researchers noted was that they did not find a link between vitamin D levels and dementia among study participants with darker skin tones.

This finding should be taken cautiously though, as it’s based on a much smaller sample size (the U.K. Biobank cohort is not very racially diverse and consists of predominantly white participants). 

Overall, having healthy vitamin D levels (supported by appropriate use of supplementation) may be a protective factor for cognitive decline.

That’s because vitamin D may help promote the breakdown of amyloid plaques—the abnormal clumps of protein in the brain that are the hallmark characteristic of Alzheimer’s disease—and mitigate inflammation. 

Achieving optimal vitamin D levels

This study adds to the importance of maintaining optimal vitamin D levels at every stage of life (especially as you age). 

And the only way to find out your vitamin D levels is to track them via a blood test. Your doctor can order a vitamin D blood test or you can measure your levels at home with one of these kits.

Knowing where your vitamin D levels stand gives you a much-needed baseline for how much you need to raise your levels or if what you’re doing is currently working. 

Now, this study used slightly different cut-off points for what’s considered deficient or insufficient for vitamin D levels. 

Typically vitamin D deficiency2 is considered to be anything less than 20 ng/mL, insufficiency is anything less than 30 ng/mL, and optimal levels are considered to be 50 ng/mL (or higher). 

Finding the right supplement

To get your vitamin D levels in that optimal range, you will likely need the support of a supplement. 

Multivitamins may be helpful (and were included in this study) as they often contain some amount of vitamin D. But that amount can vary a lot from brand to brand. Look for a multivitamin that provides at least 1,000 IU of vitamin D. 

If your vitamin D levels are really in the dumps, taking specific vitamin D supplements is warranted. A dose of 5,000 IU daily can help raise your blood levels of vitamin D. These are our top picks for vitamin D supplements that can help raise even stubbornly low levels.

The takeaway

This study reinforces the role of vitamin D on cognition and Alzheimer’s disease. While more studies are needed (especially ones including diverse populations), achieving optimal vitamin D levels is well worth the investment into a high-quality supplement.