High levels of the amino acid homocysteine, for example, have been correlated with mechanisms related to artery damage and blood clotting. * One study found that men with extremely high homocysteine levels were three times more likely to have a heart attack, and that this increased occurrence was independent of their blood lipid levels.11 Homocysteine levels can rise due to nutritional deficiencies and inborn errors of metabolism

* Ross R. Factors influencing atherogenesis. In: Hurst JW, Schlant RC, Rackley CE, Sonnenblick EH, Wenger NK, editors. The heart, arteries, and veins. New York: McGraw-Hill, 1990:877-923.