As we age, it becomes more important than ever to protect our brains. According to new research, vitamin D may help protect against dementia and cognitive decline, which is encouraging news for keeping your brain healthy.
Brain volume decreases and connections between neurons get weaker between the ages of 30 and 40. These losses often speed up after age 60, affecting the ability to think, remember, and make decisions.
However, recent studies show that vitamin D is very important for slowing down these changes that happen in the brain as we age.[1]
Let’s explore how vitamin D may help prevent dementia and cognitive impairments.
How Vitamin D Keeps Brain Volume From Losing Size
A major study looked at how vitamin D levels and brain size are related. The study looked at MRI scans and vitamin D levels in over 1,800 adults and found a strong link. In fact, lower vitamin D levels were strongly linked to smaller brain volumes and less gray matter, especially in men. [2]
These results suggest that making sure you get enough vitamin D could help protect brain structure and stop the cognitive decline that comes with getting older.
Vitamin D also helps protect the hippocampus, which is an important part of the brain for learning and remembering. Since gray matter volumes decrease with age, making sure your vitamin D levels are at their best might protect you from these damaging processes. [3]
According to the study, people who had higher levels of vitamin D kept their brain structures stronger, which could be a way to protect against the cognitive decline that comes with getting older. [4]
READ ALSO: Why Vitamin D is The Healthy Aging Dose For Women Over 50
Here’s Evidence That Vitamin D May Help Prevent Dementia
Vitamin D levels were measured in four parts of the brains of 290 deceased people in another interesting study. The researchers found a link between these concentrations and the cognitive tests that were done on the participants before they died. [5]
The results showed that people with higher levels of vitamin D had a 25–33% lower chance of getting dementia or mild cognitive impairment. People whose brains had higher levels of vitamin D had better word recall, episodic memory, and perceptual speed. This shows that this nutrient has a direct effect on cognitive performance.
An extensive study with more than 12,000 adults added to the evidence. The risk of getting Alzheimer’s disease was 40% lower in people who said they took vitamin D supplements than in people who did not say they did. [6]
The protective effect of vitamin D stayed the same even when factors like age, education level, and genetic predisposition were taken into account.
These studies have shown that taking supplements greatly reduced the risk of getting Alzheimer’s disease in women, who are already at a higher risk.
READ ALSO: 15 Tips to Help Prevent Dementia
How Vitamin D Works to Protect the Brain
While more research is being done, it is clear that vitamin D is good for brain health in many ways. Vitamin D plays a big role in a process called beta-amyloid clearance.
Beta-amyloid is a protein that builds up in the brains of people with Alzheimer’s and speeds up the breakdown of neurons. [7] The body gets rid of this protein with the help of vitamin D. Vitamin D also protects nerve cells from other proteins that are linked to dementia.
Vitamin D also seems to control immune responses, which could be another reason why it protects the brain. It might work by keeping the immune system in balance. It is known that inflammation in the brain can lead to Alzheimer’s, and amyloid deposits may be the brain’s way of trying to fight inflammation.
Vitamin D could stop this inflammatory chain reaction by changing the immune system. This would protect against cognitive decline.
It seems that taking vitamin D supplements has even more positive effects on women. The immune systems of men and women are different, and women are more likely to get autoimmune diseases.
When vitamin D levels are optimal, women’s brains may be better protected because it controls the immune system.
READ ALSO: Top 10 Brain Supplements to Support Your Brain Health
How Vitamin D and Exercise Work Together
Vitamin D and exercise may work better together to improve brain health, according to research. A study looked at what happened after a 20-week program that included cognitive training, exercise, and vitamin D supplements. [8]
When people did these activities together, their brain connections in areas like the hippocampus and angular gyrus got better. These are important for memory and attention because they are part of the brain’s default mode network.
Although exercise alone is good for brain health, vitamin D and cognitive training are even better. If you do these things daily, your brains may be more resistant to aging and cognitive decline.
Research on Vitamin D Dosage and Dementia Risk
A large study with 12,388 adults who did not have dementia showed how different kinds of vitamin D supplements might affect people. [9]
Over a ten-year period, the participants were watched, and 37% of them took supplements such as cholecalciferol, ergocalciferol, or calcium-vitamin D.
At the end of the study, 22% of the people who had taken part had developed dementia. People who took vitamin D were much less likely to get worse than people who did not take it.
Just to be specific, dementia only happened to 14.6% of people who took vitamin D supplements, but it happened to 26% of people who didn’t.
The risk of dementia was 49% lower for women who took vitamin D supplements than for women who did not take supplements. The risk was 26% lower for men. This difference between men and women makes sense when you think about how vitamin D affects the immune system and how it can help protect against Alzheimer’s.
Although experts say these results are positive, they do not prove a cause-and-effect link. The risk of dementia may also be affected by things like time spent in the sun, income, and general health habits.
More research is needed to find the best amounts of vitamin D and learn more about how it protects the body.
Recommended Dietary Allowance for Vitamin D
The recommended dietary allowances (RDAs) for daily vitamin D intake are provided in both International Units (IU) and micrograms (mcg), using the conversion rate of 40 IU per 1 microgram. 4,000 IU per day is recommended for women over 50. This limit is intended to minimize the risk of hypercalcemia, which can cause kidney and tissue damage.
READ ALSO: Why Vitamin D is The Healthy Aging Dose For Women Over 50
Closing Thoughts
The evidence surrounding vitamin D’s role in preventing dementia and cognitive impairment is compelling yet incomplete.
As more research comes in, taking vitamin D supplements, working out regularly, getting enough sleep, and living a balanced life may be the best way to keep your brain healthy.
Keep in mind that vitamin D is only one part of a multifaceted approach to preserving brain health. Focusing on overall good health can greatly lower the chance of getting Alzheimer’s or another form of dementia.
Vitamin D levels in the blood should be between 40 and 80 ng/mL for brain health, but everyone has different needs. It is best to take a combination of preventative steps early in life.
You can protect your brain function and improve your overall health by taking action today.
References
- Farghali, Mahitab, Sara Ruga, Vera Morsanuto, and Francesca Uberti. “Can Brain Health Be Supported by Vitamin D-Based Supplements? A Critical Review.” Brain Sciences 10, no. 9 (September 22, 2020): 660.
- Bonk, Sarah; Frenzel, Stefan; Garvert, Linda; Grabe, Hans Joergen; Hosten, Norbert; Nauck, Matthias, et al. (2022). Vitamin D Deficit Is Associated With Accelerated Brain Aging In The General Population Psychiatry Research: Neuroimaging 327, .
- Al-Amin, M., Bradford, D., Sullivan, R. K. P., Kurniawan, N. D., Moon, Y., Han, S.-H., Zalesky, A., & Burne, T. H. J. (2018). Vitamin D deficiency is associated with reduced hippocampal volume and disrupted structural connectivity in patients with mild cognitive impairment. Human Brain Mapping, 40(2), 394–406.
- Latimer, C. S., Brewer, L. D., Searcy, J. L., Chen, K.-C., Popović, J., Kraner, S. D., Thibault, O., Blalock, E. M., Landfield, P. W., & Porter, N. M. (2014). Vitamin D prevents cognitive decline and enhances hippocampal synaptic function in aging rats. Proceedings of the National Academy of Sciences of the United States of America, 111(41), E4359–E4366.
- Almeida, Quincy J.; Bartha, Robert; Bherer, Louis; Bray, Nick W.; Doherty, Timothy J.; Liu-Ambrose, Teresa, et al. (2023). Combining Exercise With Cognitive Training And Vitamin D3 To Improve Functional Brain Connectivity (FBC) In Older Adults With Mild Cognitive Impairment (MCI). Results From The SYNERGIC Trial GeroScience 45, 3.
- Goldman, B. (2013, September 19). Scientists reveal how beta-amyloid may cause Alzheimer’s. Stanford Medicine.
- Ghahremani, Maryam, Eric E. Smith, Hung-Yu Chen, Byron Creese, Zahra Goodarzi, and Zahinoor Ismail. “Vitamin D supplementation and incident dementia: Effects of sex, APOE, and baseline cognitive status.” Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring, March 1, 2023.
