Does Vitamin D Help With Dementia?

Vitamin D is both a nutrient we eat and a hormone our bodies make. It’s critical for bone health, and scientists are still understanding other ways it benefits the body. Studies show that vitamin D can reduce cancer cell growth, help control infections, and reduce inflammation.

Few foods naturally contain vitamin D, but some foods are fortified with vitamin D. It’s hard to get enough through food, so taking a vitamin D supplement is the best way to get enough for most people.

The main natural source of vitamin D is when it’s produced in the skin in the presence of sunlight. However, many people have insufficient levels because they live in areas where sunlight is limited in the winter or they have limited sun exposure because of being indoors much of the time. 

Low vitamin D blood levels were associated with a higher risk of dementia in a University of South Australia study. Other studies have shown that taking vitamin D can help prevent Alzheimer’s disease and other types of dementia. 

Understanding the Role of Vitamin D in Dementia Prevention

A study by the University of Calgary and the University of Exeter in the UK found that people who took vitamin D supplements were 40% less likely to be diagnosed with dementia than those who did not take vitamin D. The researchers found evidence that taking vitamin D supplements at a younger age, before the onset of cognitive decline, might be particularly beneficial in reducing the risk of dementia

On the other hand, vitamin D deficiency is known to increase the risk of developing dementia and Alzheimer’s disease. The reason vitamin D can help prevent dementia is because it stops the buildup of certain proteins in the brain, a sign of the disease. Vitamin D clears amyloid in the brain, and it may also protect against the buildup of tau, another protein involved in the development of dementia.

Sources of Vitamin D

You can get vitamin D from food, sunlight, and supplements. Sunlight exposure is the best way to get it because few foods naturally contain vitamin D. Vitamin D supplements are one of the most common nutritional supplements that people take because of the prevalence of vitamin D deficiency.

Dietary Sources of Vitamin D

While it’s difficult to get all the vitamin D you need through food, incorporating foods high in vitamin D can help.

Those foods include:

  • Cod liver oil
  • Salmon
  • Swordfish
  • Tuna fish
  • Orange juice fortified with vitamin D
  • Dairy and plant milks fortified with vitamin D
  • Sardines
  • Beef liver
  • Egg yolk
  • Fortified cereals

Healthy diet choices, in general, are tied to a lower risk of many diseases, including dementia. Here are seven other foods that are associated with a reduced risk of developing Alzheimer’s disease.

Sunlight Exposure for Vitamin D Synthesis

Sunlight exposure is the best way to get vitamin D. When the skin is exposed to sunlight, it creates vitamin D using cholesterol. The sun’s ultraviolet-B rays (UVB) rays hit cholesterol in the skin cells, which provides the energy for vitamin D synthesis (creation) to occur.

Midday, especially during summer, is the best time to get sunlight. The sun is at its highest point at noon and its UVB rays are most intense, which means you need less time in the sun to get enough vitamin D. Studies also show that the body is most efficient at making vitamin D at noon. 

A U.K. study found that 13 minutes of midday sunlight exposure three times a week during summer was enough to maintain healthy levels of vitamin D in adults.

In addition to being more efficient, getting sunlight around midday may be safer than getting sun later in the day. Afternoon sun exposure may increase the risk of dangerous skin cancers.

Vitamin D Supplements

vitamin d supplementMore than 40% of American adults are estimated to have a vitamin D deficiency, and a large portion of the world population is at risk of deficiency. Thus, many people turn to vitamin D supplements to get their recommended intake. But how and when you take these supplements can influence their effectiveness.

Vitamin D is a fat-soluble vitamin, which means it’s better absorbed in the blood when paired with high-fat foods. That’s why it’s recommended to take vitamin D supplements with a meal.

Avocados, nuts, seeds, full-fat dairy products, and eggs are nutritious sources of fat that help enhance vitamin D absorption, making breakfast a good time to take your vitamin D supplement. 

The recommended dosage of vitamin D for adults is 10 ug or 400 IU. You should not consume more than 100 ug of vitamin D per day.

Get Specialized Memory Care for Your Loved One at Terra Vista

Studies have demonstrated many ways to help prevent Alzheimer’s disease and dementia, including making healthy diet choices and getting enough vitamin D.

At Terra Vista’s Memory Care Community, our care is designed to slow the progression of dementia. We provide enriching memory-related therapies like art, music, and light therapy, and we encourage physical activity with barrier-free paths. 

Terra Vista is proudly partnered with Memory Care Corp. 

If you’re interested in learning more about our memory care center, call us at 630-793-0753 or contact us online.

Natalie Pic

Meet the Author


Natalie has compiled over eighteen years experience providing outstanding care to people with Alzheimer’s disease and dementia. In addition to being a certified Alzheimer’s and dementia care trainer, McFarland is a licensed continued education instructor for nurses and social workers through the Illinois Department of Professional Regulations. She has also developed several Alzheimer’s research partnerships. Included in those projects were Dr. Virginia Cruz, Ph.D., RN, Associate Professor of SIUE and Dr. George Grossberg, M.D., Medical Director of the Department of Psychiatry and Neurology at Saint Louis University. Natalie is a graduate of Southern Illinois University.