Written on:

12 July, 2011

What Does L-Lysine do to Cardiovascular Health?

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Heart disease remains the leading cause of death in the United States, based on 2009 data from the Centers for Disease Control and Prevention. Major risk factors include high cholesterol, hypertension and a family history of heart disease. The growing awareness of the importance of good cardiovascular health may spur new interest in dietary supplements such as L-lysine and its effects on preventing heart disease.

What Is L-Lysine?

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L-lysine, or simply lysine, is an essential amino acid, a building block of protein. A diet that includes red meat, poultry and cheese provides adequate amounts of this nutrient. Vegans, athletes and burn victims may require supplementation to meet the body's daily needs of 12mg/kg. L-lysine plays several roles in the body. It is essential for growth and for providing the necessary raw materials for energy production and calcium absorption. Calcium helps ensure proper blood clotting as well as normal muscle and nerve activity.


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Medical uses for lysine have centered around its use in treating herpes and cold sores. However, it also has shown practical applications for cardiovascular conditions. A 1991 case report by Nobel Prize-winning chemist Dr. Linus Pauling found that administration of 5g of lysine daily lessened symptoms of angina pectoris, or spasms of chest pain due to reduced oxygen to the heart, after three months of treatment in a 71-year-old man with severe coronary artery disease. Dr. Pauling reported two additional cases in 1993. He attributed the effects to the lysine's ability to relax blood vessels. This effect may also help lower blood pressure.


Scientific research has found compelling evidence that lysine may help treat atherosclerosis, or hardening of the arteries. A diet high in saturated fats contributes to the formation of plaque on the inner lining of blood vessels. The risks are twofold. First, the narrowing increases pressure within the arteries. This effect can become more deadly when plaque deposits break off, potentially blocking blood flow. A 2007 study by the Dr. Rath Research Institute in California found that lysine inhibited the biological response of muscle cells lining the arteries to form plaque in laboratory studies. Researchers recommended further investigation in live subjects.

Guidelines for Use

Despite lysine's potential benefits, exercise caution before taking a lysine supplement for cardiovascular health, especially if you are currently being treated for a cardiovascular condition. Drugs.com warns that lysine may cause gastrointestinal distress. Individuals with liver or kidney disease should avoid taking lysine. WholeHealthMD.com also cautions about possible increases in the toxicity levels of some antibiotics. Because of its impact on cardiovascular function, consult your doctor before taking a supplement because of possible interactions with medications or other dietary supplements.