Nutritional Supplements Fight High Homocysteine in Elderly
Research trials have already found folic acid, vitamin B6, and vitamin B12 to consistently lower homocysteine levels.2 3 4 Several studies have used (and some doctors recommend) 400 to1,000 mcg of folic acid per day, 10 to 50 mg of vitamin B6 per day, and 50 to 300 mcg of vitamin B12 per day. Of these three vitamins, folic acid supplementation lowers homocysteine levels the most for the average person.5 6 Even people with normal blood levels of folic acid can reduce homocysteine by taking folic acid, at least in some situations.7
In the new study, researchers surveyed 200 Argentinean men and women over the age of 65 and found normal blood levels of folic acid and vitamin B12 in the majority of participants. Their average blood homocysteine level was 13.2 micromol/L, significantly higher than the upper limit of normal for both men (11.4 micromol/L) and women (10.4 micromol/L).
The results of the new study, conducted in Argentina, may not be fully applicable to Americans. The Argentinian diet tends to be high in animal proteins and low in green leafy vegetables and other plant foods that are rich in folic acid. However, many Americans do eat a diet similar to that of Argentinians, and one survey among elderly Americans revealed markedly elevated homocysteine levels (greater than 14 micromol/L) in 29.3% of participants. Given the high rate of elevated homocysteine levels across these populations, a B-vitamin supplement seems like a good choice for men and women older than 65.
Several studies have concluded that high levels of homocysteine in the blood are associated with increased risk of heart attacks, strokes, and other cardiovascular diseases. An increase in blood homocysteine from 8 micromol/L (below 9 micromol/L is associated with the lowest risk of developing heart disease) to 13 micromol/L (the average in this study) is associated with a greater than 50% increase in the risk of heart attack or stroke.8
Homocysteine is a by-product of a normal metabolism that can build up in the blood stream of certain individuals. It is thought to somehow directly damage the walls of blood vessels, and that this damage may help start the process of hardening of the arteries. The body uses folic acid, vitamin B6, and vitamin B12 in the metabolic processes necessary to convert homocysteine into other, less toxic substances. Homocysteine can be measured in a standard laboratory test.
The relative importance of homocysteine compared with other risk factors for cardiovascular disease is still being worked out. Most researchers consider it likely, however, that at least some heart attacks and strokes are directly attributable to high homocysteine levels.
1. Janson JJ, Galarza CR, Murua A, et al. Prevalence of hyperhomocysteinemia in an elderly population. Am J Hypertens 2002;15:394–7.
2. Glueck CJ, Shaw P, Land JE, et al. Evidence that homocysteine is an independent risk factor for atherosclerosis in hyperlipidemic patients. Am J Cardiol 1995;75:132–6.
3. Ubbink JB, Vermaak WJH, van der Merwe A, Becker PJ. Vitamin B12, vitamin B6, and folate nutritional status in men with hyperhomocysteinemia. Am J Clin Nutr 1993;57:47–53.
4. Ubbink JB, Vermaak WJH, ven der Merwe A, et al. Vitamin requirements for the treatment of hyperhomocysteinemia in humans. J Nutr 1994;124:1927–33.
5. Dierkes J, Kroesen M, Pietrzik K. Folic acid and vitamin B6 supplementation and plasma homocysteine concentrations in healthy young women. Int J Vitam Nutr Res 1998;68:98–103.
6. Stein JH, McBride PE. Hyperhomocysteinemia and atherosclerotic vascular disease: pathophysiology, screening, and treatment. Arch Intern Med 1998;158:1301–6.
7. De Vecchi AF, Patrosso C, Novembrino C, et al. Folate supplementation in peritoneal dialysis patients with normal erythrocyte folate: effect on plasma homocysteine. Nephron 2001;89:297–302.
8. Boushey CJ, Beresford SA, Omenn GS, Motulsky AG. A quantitative assessment of plasma homocysteine as a risk factor for vascular disease. Probable benefits of increasing folic acid intakes. JAMA 1995;274:1049–57.
Matt Brignall, ND, is in practice at the Seattle Cancer Treatment and Wellness Center and at the Evergreen Integrative Medicine Clinic in Kirkland, WA. He specializes in integrative treatment of cancer. He is a contributor to Healthnotes and Healthnotes Newswire.
Copyright © 2002 Healthnotes, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.A new study has found that more than 90% of people with low blood levels of either vitamin B12 or folic acid have high levels of homocysteine, an easily modifiable risk factor for heart disease. Moreover, 70% of older people, even many with normal levels of vitamin B12 and folic acid, have high homocysteine.