Lysine is an essential amino acid, which means it is not manufactured by the body. It is necessary to the body's ability to build proteins and may help support the immune system against outbreaks of the herpes simplex virus. There is insufficient evidence, however, for its use as general immune system support.
Lysine
As an amino acid, lysine, or L-lysine, is an essential building block of protein. It is also important to bone, skin and muscle health. It is necessary to produce carnitine, a nutrient that helps the body convert fatty acids into energy. It may also assist in calcium absorption for strong bones, and collagen production. Collagen is a crucial component of bones, tendons, cartilage and skin. Lysine deficiency can result in fatigue, anemia, poor appetite, dizziness and fatigue. It also creates the conditions necessary to outbreaks of the herpes simplex virus.
Herpes Simplex Virus
Herpes simplex virus Type 1 can cause cold sores, while Type 2 causes genital herpes. Both forms of the virus appear to need high levels of the amino acid arginine, or L-arginine, to replicate. Lysine helps block arginine production. This may help reduce the frequency and severity of cold sore and herpes outbreaks in those infected with the herpes virus. The Langone Medical Center at New York University references a number of double-blind, placebo-controlled studies in which lysine was effectively used to prevent outbreaks. It seems to work only as a preventative, however, not as a treatment for outbreaks once they occur.
Dietary Lysine
Red meat, pork and poultry are the best dietary sources of lysine. Protein-rich fish such as cod and sardines also have high lysine levels. Vegetarians and vegans should be particularly careful to get enough dietary lysine from sources such as Parmesan cheese, nuts, soy, eggs, spirulina, beans, peas and lentils. Brewer's yeast also offers lysine, and can be sprinkled on or added to many foods.
Dose and Warnings
The University of Maryland Medical Center recommends that adults consume about 5 mg of lysine per pound of body weight per day. To support the immune system against herpes outbreaks, try 1,000 mg in supplement form three times a day. Only your doctor can diagnose and recommend treatment for herpes, however. High doses of dietary and supplemental lysine have caused high cholesterol and gallstones in animals. If you are prone to these conditions, have kidney or liver disease or are pregnant, speak with your doctor before taking lysine supplements.
