L-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 helps the body absorb and conserve calcium. Lysine has many functions in the body because it is incorporated into many proteins, each of which is used by the body for a variety of purposes. Lysine interferes with replication of herpes viruses and is therefore often prescribed by nutritionally oriented doctors to people with cold sores, fever blisters or genital herpes. Beta Glucan is an insoluble fiber that has been isolated from the cell wall of baker's yeast. Solaray Beta Glucan is a quality, polybranched material that consists of beta 1,3 and 1,6 linkages.