Lysine is an essential amino acid needed for growth and to help maintain nitrogen balance in the body. Essential amino acids cannot be made in the body and must be supplied by the diet or supplements.
Lysine appears to help the body absorb and conserve calcium .
1 Linus Pauling believed that lysine helps maintain healthy blood vessels, an idea based on biochemistry and results from three people with angina pectoris who responded to lysine supplementation. Lysine interferes with replication of herpes viruses and is therefore often prescribed by nutritionally oriented doctors to people with cold sores or genital herpes. A review of the research trials investigating the effects of lysine on people with cold sores shows that most though not all trials support the use of lysine. Brewer's yeast, legumes, dairy, wheat germ, fish, and meat all contain significant amounts of lysine. Athletes involved in frequent vigorous exercise have increased need for essential amino acids, although most diets meet these increased needs.