Homocysteine Levels and Cholesterol

            Homocysteine is an amino acid produced by the body. In 1969, Dr. Kilmer McCully, a graduate of Harvard Medical School, conjectured that high homocysteine levels might cause coronary heart disease (CHD) and atherosclerosis. This hypothesis contradicted the mainstream belief that high cholesterol levels in the blood posed the greatest risk of CHD. He believed this to be true because he found patients that had normal cholesterol levels and yet suffered from CHD. In 1990, he examined 194 autopsies to determine the proportion of cases of atherosclerosis that did not have one of the well-known risk factors for atherosclerosis, such as diabetes mellitus, hypertension, or elevated cholesterol levels. In 74% of all cases, total cholesterol levels were well within what we define as a normal range for cholesterol, specifically 200 mg/dL or below.

            The take-home message of this novel study is that CHD can and does develop without evidence of diabetes, hypertension, or elevated cholesterol. These results further intensified McCully's belief that other factors, like high levels of plasma homocysteine, are conceivably a cause of atherosclerosis.

            Other studies in the 1990’s, could not conclusively prove that high levels of blood homocysteine where the cause of CHD. Hi levels of blood homocysteine might be an indicator of coronary problems, but is it is the cause? The jury is still out.

            Most doctors treat high levels of homocysteine with the B vitamins B6, B12, and B9 (folic acid). Confer with your doctor if you are wondering about your homocysteine levels.