Homocysteine and cardiovascular disease: a systematic review of prospective studies

Researchers combined results from studies that followed adults over time. They compared blood levels of homocysteine, an amino acid made in the body, with later cardiovascular disease, meaning heart and blood-vessel problems. People with higher homocysteine levels generally had a higher risk of these problems. However, these studies observed links and could not prove that homocysteine itself caused the disease.

What this means for you: This does not show that buying homocysteine-lowering supplements will prevent heart disease. Focus on proven steps such as not smoking, exercising, and controlling blood pressure and cholesterol unless a clinician finds a specific deficiency.