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.