Vegetables And Dietary Supplementation Protect Against Alzheimer’s

August 30, 2005

Elderly persons who get adequate amounts of folic acid have a 55% reduced risk of getting dementia induced by Alzheimer’s disease, says an American study.

Lack of the B vitamin folic acid is probably the most common deficiency in Denmark. Too few people manage to chew the 2-300 grams of green vegetables that are needed every day if they want the recommended 0.3 mg from the diet. In the United States, 0.4 mg is recommended, but here grain products are legally enriched with folic acid.

Most women know that if they are planning a pregnancy, they should take folic acid (0.4 mg/day) to avoid the risk of giving birth to a child with spina bifida. Fewer know that there is much evidence that folic acid also protects against atherosclerosis and even certain types of cancer.

Several studies have suggested that folic acid also prevents Alzheimer’s dementia. But now the first issue of a new scientific journal for the American Alzheimer’s Association opens with a very tangible result: Elderly people who get at least the recommended 0.4 mg of folic acid per day develop Alzheimer’s less than half as often as others!

If this is not just a statistical coincidence, the significance is enormous. One in five adults will eventually develop Alzheimer’s, and few of them may be getting the protective 0.4 mg of folic acid a day. Almost all (87%) of those who reached the target in the American study were taking vitamin pills as a supplement.

The study followed 579 elderly men and women. Of these, 57 developed Alzheimer’s over the next nine years, but the risk was clearly reduced (to 45%) in that third who got enough folic acid. It is important to note that it was irrelevant whether the folic acid came from vegetables or vitamin supplements. No similar association was found with other vitamins.

This finding is supported by others, but it must be emphasized that it only shows correlations, not causes. On the other hand, one can easily imagine a causal relationship. Alzheimer’s is caused by the deposition in the brain of the substance beta-amyloid, which is so toxic to brain cells that they can die. With a lack of folic acid, the body’s content of the equally harmful homocysteine ​​increases, which can therefore be thought to enhance the toxic effect of beta-amyloid. This is actually supported by animal studies.

Another explanation has to do with the importance of folic acid in the so-called one-carbon metabolism. Together with vitamin B12, folic acid is responsible for the supply of very small biochemical building blocks – so-called methyl groups, which contain one carbon atom. These small building blocks are used in the construction of a variety of proteins in addition to DNA. A lack of folic acid can therefore affect the mechanisms that normally prevent the deposition of beta-amyloid. This is also supported by scientific experiments.

However, the formation of beta-amyloid with the subsequent destruction of brain cells is a very complicated process, in which several enzymes, DNA, proteins that take care of cholesterol, free oxygen radicals, etc. play a role.

This is reflected in the Alzheimer’s Association’s very general advice for those who want to avoid Alzheimer’s: Stay mentally and physically active, eat a low-fat diet, and keep cholesterol levels low. Also, get plenty of dark-colored fruits and vegetables.

It is in these vegetables and fruits that folic acid is found. What is new is that folic acid is now being pointed out much more directly as a preventive factor, albeit with reservations.

By: Vitality Council

References:
1. Corrada MM. et al. Alzheimer’s & Dementia. 2005;1:11-18.
2. Fuso A. et al. S-adenosylmethionine/homocysteine cycle alterations modify DNA methylation status with consequent deregulation of PS1 and BACE and beta-amyloid production. Mol Cell Neurosci. 2005 Jan;28(1):195-204.
3. Quadri P. et al. Homocysteine, folate and vitamin B12 in mild cognitive impairment, Alzheimer disease aqmd vascular dementia. Am J Clin Nutr 2004,80:114-22

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