Among the many indicators for heart disease risk, high homocysteine levels is one of the more reliable ones. In 2006, in a study of women and heart disease, women who had a high level of the amino acid homocysteine were 4 times more likely to die of heart disease.
Homocysteine is formed when protein is broken down in the body. It seems to play a role in injuring artery walls and increasing the likelihood of blood clots. These two effects can increase your risk of stroke or a heart attack.