Vitamin D, Calcium Supplementation May Not Reduce Dementia Risk

Vitamin D and calcium supplementation may not reduce the risk of dementia or mild cognitive impairment, according to a recent study.

Vitamin D is found in many dietary sources, such as fish, eggs, fortified milk and cod liver oil. The sun also contributes significantly to the daily production of vitamin D, and as little as 10 minutes of exposure is thought to be enough to prevent deficiencies. In older patients, intake of vitamin D is associated with better cognitive test performance; however, further research is needed.

Calcium is the most abundant mineral in the human body and has several important functions. More than 99 percent of total body calcium is stored in the bones and teeth where it supports the structure. The remaining one percent is found throughout the body in blood, muscle and the intracellular fluid. Calcium is needed for muscle contraction, blood vessel constriction and relaxation, the secretion of hormones and enzymes, and nervous system signaling. A constant level of calcium is maintained in body fluid and tissues so that these vital body processes function efficiently.

In a new study, researchers randomly assigned 2,034 women at least 65 years-old without dementia at the beginning of the study to receive 1,000 milligrams of calcium with 400 international units of vitamin D and 2,109 women to receive a placebo.

Throughout the average 7.8 year follow-up period, 39 women in the vitamin D and calcium group, and 37 women in the placebo group developed dementia. Similarly, mild cognitive impairment was seen in 98 and 108 women in the treatment and placebo groups, respectively. The researchers found that significant differences in the risks of dementia or cognitive impairment between the treatment and placebo groups were lacking.

The authors concluded that supplementation with vitamin D and calcium may not reduce the risk developing dementia or mild cognitive impairment. Additional research in this area is warranted.

In addition to vitamin D, many other integrative therapies have been studied for their potential benefits in dementia and cognitive impairment. Overall, the scientific literature does suggest that ginkgo benefits people with early-stage Alzheimer's disease and multi-infarct dementia, and it may be as helpful as acetylcholinesterase inhibitor drugs such as donepezil (Aricept®). Well-designed research comparing ginkgo to prescription drug therapies is needed. Preliminary studies have found positive effects of Panax ginseng in the treatment of elderly individuals with symptoms of senile dementia. Additional research is needed before a conclusion can be made.

For more information about integrative therapies for dementia, please visit Natural Standard's Comparative Effectiveness Database.

For more information about vitamin D and calcium, please visit Natural Standard's Foods, Herbs & Supplements Database.

Comments

[NL]

It is unfortunate that there are not many effective treatment options for dementia and Alzheimer's disease. This study clearly indicates that research is still needed in these areas before definitive treatment recommendations can be made.

[ML]

I have never heard of vitamin D and calcium supplementation helping dementia. I wonder if there is a study that uses the supplementation on patients that already have mild dementia rather than people without previous history of dementia. I believe results from a study designed with patients with a history of dementia are more impactful. I know that gingko can be helpful with dementia and it has effects equal to donepezil. I do agree with others that supplementation is important in this patient demographic anyway.

[km]

Even though this study shows that Vit D and Calcium do not reduce risk of dementia in elderly, they are still excellent supplement for them since they also prevent risk of osteoporosis. Ginseng on the other hand has been used in Asian culture for centuries as they are believed to regenerate cells, increase cell growth and benefit overall health. These studies really benefit patients in term of providing an alternative and more natural therapy than traditional medications.

[ac]

"Well-designed research comparing ginkgo to prescription drug therapies is needed" - It is often frustrating that there are not more well done head-to-head trials done, even among prescription drugs, to compare the efficacy of one drug to another. It makes it difficult to give patients a drug recommendation when mostly non-inferiority trials are being done.

[af]

I found this excerpt to be particularly interesting for a couple of reasons. First, when I learned about dementia and Alzheimer’s in school, I did learn about Vitamin D’s role in reducing the risk of developing dementia. This study, which suggests otherwise, is a perfect example of how the healthcare field is always evolving, and for this reason, it is important for healthcare providers to stay up-to-date by reading current studies and literature. In addition, I thought it was interesting to learn that an herb (ginkgo) is possibly as effective as drugs proven to be effective in managing patients with dementia and Alzheimer’s disease, like Aricept. This is an example of how studies on herbs may prove to be clinically useful.

[SC]

Although Vitamin D may not reduce dementia risk it is still a very important vitamin to take in order to increase calcium absorption in the gut. After looking at the study it looks like the mean age of the participants was 71 years old. The NIH’s recommended daily intake of Vitamin D for people up to age 70 is 600IU daily and for 71+ years old is 800IU daily. I wonder why the researchers chose to use a dose of Vitamin D 400IU.

[JS]

I’ve never heard about low levels of vit D being a risk factor for dementia. However, I do remember learning how vit E was used as an adjunctive treatment option for Alzheimer’s. The theory behind using vit E was because of its use as an antioxidant which was suppose to help with the accumulation of free radicals and oxidative stress (2 things thought to have contributed to Alzheimer’s disease). Now vit E is not usually recommended due to a meta-analysis that demonstrated that high dose vit E actually increased mortality. I think this shows what a tough condition Alzheimer’s is to treat and how, like many people already pointed out, we don’t have a definitive cause for the condition. But maybe by looking at vitamin deficiencies/supplementation somehow we can pin point factors that may contribute to the onset of Alzheimer’s and dementia.

[JH]

Vit D is important for maintaining the health of the brain's vasculature. This is particularly critical for many elderly who are at risk of Vascular Dementia. Recent evidence also suggests that Vit D may enhance the clearance amyloid from the brain. Amyloid is a protein that condenses into plaques in the brain of patients with Alzheimer's disease. Some researchers speculate that enhancing the removal of amyloid from the brain might reduce the symptoms of dementia. Thus Vit D may offer at least two ways to protect the brain from the changes often associated with pathological aging.
Vit D deficiency may have other consequences upon brain health as we age; low levels of this vitamin have been recently associated with an increased risk of Parkinson's disease.

[tx]

I agree with Mahsa in that if we do not know the cause of Alzheimer's, it will always remain difficult to treat. Many treatment options available simply slow the progression of the disease, instead of stopping or reversing dementia symptoms. Alzheimer's disease is a vast area of study at this point, and it is hard to say that vitamin D definitely does not help with Alzheimer's disease progression. Further research is clearly warranted.

[dp]

I didn't realize that vitamin D and calcium supplementation were ever believed to decrease the risk of dementia. There are very few treatments that seem to work to decrease the risk of dementia. Even prescription medications available for dementia are only marginally effective. Despite this study, vitamin D and calcium supplementation is still important to promote bone health and decrease the risk of osteoporosis.

[Mahsa Salsabili]

The exact cause of Alzheimer's has not yet been found. Therefore it makes treatment difficult. Vitamin D has been shown to reduce inflammation, if it were to work in dementia patients it would only relieve the symptoms but would not cure the disease. A potential therapeutic target for Alzheimer's disease is the amyloid beta protein further studies are being performed on the protein.

[Mariana Markell, MD]

This study's conclusion is flawed in that they focused on weight loss. Clearly, lean body mass is probably as important or more important for health. As the resistance training group's lean body mass increased, they did not lose as much weight, because muscle weighs more than fat. The best exercise is the one that a person will do. Period.