What Is Homocysteine?

Homocysteine is an amino acid in the blood. It is produced by the body, usually as a byproduct of consuming meat.
Epidemiological studies have shown that too much homocysteine in the blood (plasma) is related to a higher risk of coronary heart disease, stroke and peripheral vascular disease.

What causes a high homocysteine level?

Homocysteine is normally changed into other amino acids for use by the body.
If your homocysteine level is too high, you may not have enough B vitamins to help this process take place. Or you may not have enough of the chemicals (enzymes) your body uses to process homocysteine.

Most people with a high homocysteine level don't get enough folate (also called folic acid), vitamin B6 or vitamin B12 in their diet. Replacing these vitamins helps return the homocysteine level to normal. Other possible causes of a high homocysteine level include low levels of thyroid hormone, kidney disease, psoriasis, or some medicines.

How is a high homocysteine level harmful?

High homocysteine levels in the blood can cause cholesterol to change to something called oxidized low-density lipoprotein, which damages the arteries. In addition, high homocysteine levels may make blood clot more easily than it should.
This can increase the risk of blood vessel blockages. A blockage might cause you to have a stroke. It might also make a problem with blood flow, such as atherosclerosis, worse.

How can homocysteine levels be lowered?

The consumption of folic acid supplements or cereals that are fortified with folic acid, and to a lesser extent vitamins B6 and B12, can lower blood homocysteine levels.