Recommended Dose For Lysine

Amino acids are nitrogen-containing molecules that serve as building blocks for proteins, which are the basis for a vast array of enzymes, hormones, antibodies and structural elements in your body. Amino acids also function as substrates or precursors for many non-protein molecules such as neurotransmitters. Only 20 amino acids are needed to fulfill all of these roles. Ten of these -- the "essential" amino acids -- cannot be synthesized in your body and must be obtained from your diet. Lysine is an essential amino acid.

Lysine Functions

One of lysine's primary functions is in the synthesis of collagen. Collagen is the most abundant protein in your body, comprising the structural underpinnings of your bones, muscles, cartilage, skin, eyes and soft organs. Lysine is also needed to produce carnitine, a compound that is crucial for efficient fatty acid metabolism. An August 1988 article in "The American Journal of Clinical Nutrition" cites lysine's role in intestinal calcium absorption and, thus, its contribution to bone health. Lysine is instrumental in immune function, as evidenced by its utility in combating some viral illnesses.

Herpes

According to scientists at Southern California University of Health Sciences, lysine inhibits Herpes simplex virus, making it useful for treating this chronic and recurrent viral infection. Nutritionist Elson Haas, M.D., recommends a lysine dosage of 1,500 mg daily -- 500 mg taken 3 times daily -- during a herpes outbreak and 500 mg daily as a preventive between outbreaks. Not all herpes sufferers benefit from lysine supplementation; lysine appears to be more beneficial for facial herpes than genital herpes.

Athletic Performance

Since lysine is needed for the production of carnitine and carnitine is required for the metabolism of fatty acids, lysine is used by body builders, athletes and people trying to lose weight to help boost carnitine synthesis. For improving muscular metabolism, Haas recommends 500 mg of lysine 2 to 3 times daily or a single bedtime dose of 1,000 to 1,500 mg. Notably, at a March 2004 National Institutes of Health conference in Bethesda, Maryland, Dr. Eric Brass from the U.C.L.A. School of Medicine reported that carnitine supplementation did not confer measurable benefits in energy metabolism or athletic performance. Lysine's usefulness for this purpose is similarly unproven.

Daily Needs

Lysine is an essential amino acid, so it must be acquired from dietary sources or supplements. Daily requirements are estimated to be 750 to 1,000 mg daily. Foods that are rich in lysine include fish, red meats, poultry, eggs and dairy products. Wheat germ, tofu and legumes are also relatively good sources of lysine. Some uses of supplemental lysine are not supported by scientific evidence. A well-balanced diet is the best means of obtaining sufficient amounts of this important amino acid.