Lysine supplements are touted as a natural remedy for a number of health problems, including cold sores, genital herpes, and shingles. Also known as “L-lysine,” lysine is an essential amino acid thought to help the body produce infection-fighting antibodies, enzymes, hormones, and body tissues. Proponents claim that lysine supplements can also boost the immune system, as well as aid in muscle repair. Some lysine supplements contain a combination of lysine and L-arginine, another essential amino acid.

The Science Behind Lysine Supplements

Although research on the use of lysine supplements is limited, some studies suggest that lysine supplements hold promise as a treatment for certain health conditions. Here’s a look at a few key study findings:

1) Cold Sores

Studies show that lysine supplements and lysine-based ointment may shorten the duration of cold sore outbreaks by keeping the herpes simplex virus from replicating. In a 2005 study of 30 patients, for instance, scientists found that cold sores cleared up in 40 percent of participants after three days of using a lysine-based ointment. By the sixth day of treatment, cold sore symptoms were resolved in 87 percent of patients. (When left untreated, cold sores may last up to 21 days.)

2) Anxiety

For a report published in 2010, researchers looked at 24 studies on the use of dietary supplements in treatment of anxiety. Along with kava and passionflower, a combination of L-lysine and L-arginine was found to be one of the most effective supplements for anxiety relief. Earlier research shows that supplements containing a combination of L-lysine and L-arginine may help alleviate anxiety by normalizing certain hormones involved in the stress response.

3) Osteoporosis

Preliminary research in animals suggests that lysine supplements may increase the body’s absorption of calcium and, in turn, protect against bone loss. However, scientists have yet to determine if lysine supplements can help prevent osteoporosis in humans.

Should You Take Lysine Supplements for Health Purposes?

Most people can get their fill of lysine by following a balanced diet containing high-protein foods (such as nuts, beans, eggs, and soy). If you’re interested in using lysine supplements to treat or prevent a specific health problem, make sure to consult your physician before starting your supplement regimen.