Homocysteine << `hoh` muh SIHS tee een >> is a potentially harmful substance found in the bodies of human beings and other animals. It is produced from the breakdown of an amino acid (building block of protein) called methionine << muh THY uh neen >> . Methionine is used in the body for production of glucose and the breakdown of fats in the liver. Medical researchers are interested in homocysteine because high levels of the amino acid in the blood may increase a person’s risk for heart disease, stroke, or Alzheimer’s disease. Scientists have also found that high levels of homocysteine appear to increase the risk of bone fractures in individuals with osteoporosis, a weakening of bones through the loss of bone tissue.
Too much homocysteine can damage blood vessels, causing cholesterol to build up inside them. This build-up contributes to heart disease. Cholesterol is a fatty, waxy substance found in animal tissues and the foods made from them. Researchers have found that significant numbers of people who suffer or die from heart disease also have high homocysteine levels in their blood. High homocysteine levels may also make blood clot more easily, increasing the risk of blood vessel blockage. Such blockages can lead to stroke.
Some people have high levels of homocysteine in their blood due to a genetic mutation that affects the way methionine is broken down. People may also develop high levels of homocysteine in their blood if they do not get enough folic acid, also called folate, in their diet. Folic acid, one of the B-complex vitamins, breaks down homocysteine in the body so it can be cleared from the bloodstream.
People can reduce the level of homocysteine in their blood and possibly lower their risk of heart disease by increasing the amount of folic acid in their diet. The vitamin is found in small amounts in green leafy vegetables, citrus fruits and juices, dried beans, nuts, and milk. Other sources include vitamin supplements, and grain and cereal products fortified with folic acid. Physicians recommend a diet rich in fruits and vegetables along with regular exercise to reduce the risk of heart disease.
Most people do not know their blood homocysteine level. Blood tests for homocysteine are rarely done because of their high cost.
