Want to boost brain health and prevent dementia? Vitamin D supplementation is the key, says study

07/03/2024 / By Evangelyn Rodriguez

Vitamin D is often linked to many health benefits such as strong bones and teeth and a healthy immune system. Reports also suggest that having adequate levels of vitamin D can help reduce your risk of depression. But science says vitamin D can offer more.

According to a recent study by researchers from Canada and the U.K., supplementing with vitamin D can also help reduce your risk of dementia. Dementia is an umbrella term for cognitive issues that commonly plague older adults, often characterized by an impaired ability to think, remember or make decisions. Alzheimer’s disease is the most common form of dementia, and it affects an estimated 6.9 million Americans aged 65 and older today.

Vitamin D: a potent nutrient for dementia prevention

Numerous studies have long reported about the connection between vitamin D deficiency and dementia. For instance, a 2014 study published in the journal Neurology analyzed data from 1,658 older adults and found that being deficient in vitamin D substantially increased their risks of all-cause dementia and Alzheimer’s disease. However, despite this association, the potential of vitamin D supplementation to lower these risks remains largely unexplored.

To address this, researchers from the University of Calgary and the University of Exeter conducted a prospective cohort study to investigate the effects of vitamin D on dementia incidence. All data used in the study came from the National Alzheimer’s Coordination Center database, a centralized data repository for the National Institute of Aging’s (NIA) Alzheimer’s Disease Research Centers (ADRC) Program, and were obtained from a total of 12,388 participants. These individuals were all dementia-free at the beginning of data collection (baseline).

The researchers divided the participants into two groups: those with baseline exposure to vitamin D and those without prior to the onset of dementia. They also looked at the effect of three different types of vitamin D supplement, namely, calcium–vitamin D, cholecalciferol and ergocalciferol. They hypothesized that taking any of these commonly used vitamin D supplements would be associated with a lower incidence of dementia. (Related: 6 Mushrooms you can eat to prevent cognitive impairment and reduce your dementia risk.)

Aside from age, sex, education, race, cognitive diagnosis and depression, the researchers also adjusted for apolipoprotein E (APOE) e4 status. APOE is a protein that combines with lipids to form lipoproteins, which are responsible for packaging and transporting cholesterol through the bloodstream. The APOE gene has three versions, one of which (e4) has been found to increase a person’s risk of developing early-onset Alzheimer’s disease. The APOE e4 allele can be inherited from one or both parents, with the latter case resulting in an even greater risk of Alzheimer’s.

Data analyses revealed that exposure to any form of vitamin D was associated with significantly longer dementia-free survival as well as a lower incidence rate of Alzheimer’s compared to no exposure. In fact, supplementing with vitamin D reduced dementia risk among the participants by 40 percent. The researchers also noted that the effects of vitamin D were significantly greater among women than men and among those with normal cognition than those with mild cognitive impairment.

Lastly, the researchers noted that the “effect of vitamin D on [dementia] incidence rate differed significantly across the strata of sex, cognitive status, and APOE e4 status.” In particular, the effects of vitamin D supplementation were significantly greater among individuals who did not carry the APOE e4 gene than those who inherited the gene from either one or both parents.

Although the researchers were unsure why the participants visited an ADRC and why they were taking vitamin D supplements, their findings nevertheless “implicate vitamin D as a potential agent for dementia prevention and provide additional support for its use in at-risk individuals for [Alzheimer’s disease] dementia.”

Vitamin D is important for brain function

In an earlier study published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, researchers at Tufts University in Massachusetts sought to understand the role of vitamin D in the brain and why a person’s vitamin D levels have a huge impact on his cognitive performance. Lead author Kyla Shea, an associate professor at the Friedman School of Nutrition Science and Policy at Tufts, explained that they “wanted to know if vitamin D is even present in the brain, and if it is, how those concentrations are linked to cognitive decline.”

To achieve their objective, the researchers examined brain samples collected from 209 participants in the Rush Memory and Aging Project, a long-term study whose goal was to identify the post-mortem indices linking genetic and environmental risk factors to the development of Alzheimer’s. They looked for vitamin D in four different regions of the human brain.

Two of those brain regions are associated with changes observed in Alzheimer’s disease, while one is associated with forms of dementia that have been linked to blood flow. The last region has no established link to Alzheimer’s or vascular disease-related cognitive decline. (Related: Research shows Lion’s mane mushroom can combat dementia and cognitive decline.)

The researchers found that vitamin D is a natural component of brain tissue. In fact, the presence of high levels of vitamin D in all four regions of the brain that they examined correlated with better brain performance and a 25 to 30 percent lower risk of dementia or mild cognitive impairment. The researchers identified 25(OH)D3, or calcifediol, as the most abundant form of vitamin D in brain tissue.

Inadequate levels of vitamin D have been shown to have a detrimental effect on brain structure and function. In mice, vitamin D deficiency not only affects their learning ability but also reduces perineuronal nets in the hippocampus, the part of the brain associated with learning and memory formation. These perineuronal nets are said to act like scaffolding in the brain that helps stabilize the connections between brain cells (neurons).

Researchers believe that insufficient vitamin D levels in the brain cause these perineuronal nets to weaken, making them more susceptible to degradation by enzymes. Because neurons in the hippocampus cannot maintain connections without these supportive nets, cognitive functions associated with the hippocampus, such as learning, short- and long-term memory and visual-spatial memory, become impaired. This is why maintaining healthy vitamin D levels is important for brain health and function.

Despite these findings, researchers caution adults not to take large doses of vitamin D without first consulting a healthcare professional. Too much vitamin D can cause calcium to build up in your blood — a condition known as hypercalcemia. Vitamin D toxicity can also cause bone pain and calcium stones to form in your kidneys.

The recommended daily intake of vitamin D for adults 51 to 70 years of age is 15 micrograms (mcg) or 600 International Units (IU). For adults 71 years old and above, the recommended daily vitamin D intake is 20 mcg or 800 IU. Adults aged 19 to 50 years are also advised to get 15 mcg or 600 IU of vitamin D every day. (Related: Vitamin D supplementation can REDUCE cancer death risk by 16%, study shows.)

Two forms of vitamin D are present in foods of supplements: vitamin D2, or ergocalciferol, and vitamin D3, or cholecalciferol. Both forms of vitamin D are well-absorbed in the small intestine.

For the latest research about vitamin D, visit VitaminD.news.

Watch the following video to learn about vitamin D for brain power and mood benefits.

This video is from the Holistic Herbalist channel on Brighteon.com.