Information On Homocysteine (High)

A high serum concentration of homocysteine is associated with increased risk for Coronary Heart Disease (CHD). The AHA recently published an advisory on homocysteine that provides an in-depth review of the relation between homocysteine and CVD. Several mechanisms whereby elevated homocysteine predisposes to CVD have been postulated. However, it remains to be proved in controlled clinical trials that a reduction in serum homocysteine levels will reduce risk for CHD. In some patients, nonetheless, high levels of homocysteine can be lowered by recommended daily intake of folic acid. If homocysteine levels are elevated, patients should be encouraged to consume the recommended daily intake of folic acid, as well as vitamins B6 and B12. Routine measurement of homocysteine levels was not recommended for purposes of risk assessment, but measurement is optimal in high-risk patients.

The observation that many heart attack victims have normal cholesterol levels underscores the need to identify other risk factors for atherosclerosis. Of several substances in the blood that are now thought to predict odds for vascular disease, the amino acid, homocysteine, is the one for which the case is strongest. The findings suggest a simple way to prevent heart attacks because homocysteine levels can be lowered by taking the B vitamin, folic acid. In a 1995 review of work exploring the relationships among homocysteine levels, folic acid and blood vessel disease (JAMA, vol. 274, pp.1049-1057), University of Washington researchers proposed that increasing folic acid intake might prevent as many as 50,000 heart attack deaths a year.

An important risk factor for vascular disease is elevated blood concentrations of homocysteine, and one of the risk factors for hyperhomocysteinemia is inadequate intake of the vitamins involved in homocysteine metabolism. Homocysteine is an intermediate in the interconversion of the amino acids methionine and cysteine, a process requiring at various stages, activated folic acid (tetrahydrofolate and N-methyl-tetrahydrofolate) and enzymes containing the cofactors vitamin B6 (pyridoxal phosphate) and vitamin B12 (methyl- cobalamin). Homocysteine is toxic to the vascular endothelium but undergoes rapid enzymatic metabolism so it is not normally present in the bloodstream. However, a surprisingly large number of people have elevated blood levels of homocysteine, in some cases because of a genetic inability to metabolize homocysteine and in other cases because of a deficiency of one or more vitamin cofactors required for its conversion. Such individuals are at increased risk of peripheral vascular, cardiovascular, and cerebrovascular disease.

Folic acid is thought to protect against heart disease because it breaks down homocysteine and allows it to be cleared from the blood stream. The University of Washington review referred to 11 studies of folic acid's effects on homocysteine levels. Among these was the Tufts research, which showed for the first time that inadequate intake of the vitamin is the main determinant of the homocysteine-related increase in the risk of carotid blockage.

The nutrients mentioned above reflect the major nutritional supplements that may help the condition. Please do remember however that nutritional supplementation is an adjunct to medical treatment and in no way replaces medical treatment.

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