What is L-lysine? What is L-lysine found in?

L-Lysine is an essential amino acid required for protein biosynthesis and is abundant in lamb, pork, eggs, red meat, fish oil, cheese, beans, peas, and soy. Amino acids are the building blocks of protein and work together for a variety of important biochemical reactions.

What are the benefits of L-lysine?

Cold sore reduction

One of the most common supplement uses of L-Lysine is to inhibit the normal replication of Herpes simplex virus (HSV) in particular relation to the onset of cold sores, shortening the normal course and duration of the outbreak[1]. However, for additional benefit, this supplement regime should also be followed with a low arginine diet[2].

A study found that when used topically with zinc and a herbal-based product, L-lysine significantly reduced the duration of cold sore outbreaks. By the third day, 40% of participants experienced full resolution, and by the sixth day, 87% experienced full resolution. Another study showed that oral supplementation with lysine prevented recurrence or reduced the frequency of herpes infection in 84% of participants, with improved symptom severity and faster healing time compared to those not taking lysine.

Mental health

In addition to the above, L-lysine has also shown benefits for those struggling with mental health conditions such as anxiety. A study in Japan showed treatment with L-lysine significantly reduced both trait anxiety and state anxiety induced by cognitive stress. In addition, they found that treatment with L-lysine along with L-arginine decreased the basal levels of salivary cortisol (our stress hormone) too[5].

Please note

When taking L-lysine in supplement form, it is recommended to take this away from foods to ensure best results.