Lysine: what benefits for the body and recovery?

What is lysine?

Lysine is an essential amino acid.

This means that the body cannot synthesise it itself, even though it needs it. It must therefore be obtained from the diet.

Lysine is found in foods rich in animal proteins (meat, fish, eggs, dairy products, etc.), in certain foods rich in plant proteins (lentils, kidney beans, quinoa, etc.) and in nutritional supplements (capsules, tablets, powder) that are particularly popular with sportspeople.

Lysine is known to be a component of structural proteins such as collagen.

The various benefits of lysine

Support for muscle recovery

One of the best-known actions of lysine in the human body is its role in muscle recovery.

Amino acids are the basic building blocks of protein and, as an essential amino acid, lysine is involved in the synthesis of the proteins that make up muscles. 

As such, it is thought to promote the repair of damaged muscle fibres after intense physical effort. It therefore supports recovery after training, a competition or a demanding physical activity.

In addition, studies show that it also helps to reduce muscle catabolism, i.e. the breakdown of muscles subjected to major effort (2), particularly in situations of stress or overtraining.

These properties explain why lysine consumption is so popular in sport.

Role in collagen production

In the human body, lysine is directly involved in the formation of collagen. This protein is essential for the formation and structure of connective tissue (skin, tendons, ligaments, cartilage, bones).

Lysine acts as a cofactor in reactions involving the enzymes that stabilise collagen fibres and guarantee their strength and elasticity (3).

This process is particularly important for promoting wound healing, joint health and skin tone.

In the event of lysine deficiency or increased needs (ageing, injuries, surgery), supplementation is therefore recommended to promote better tissue regeneration.

Contributes to calcium absorption

From a biological point of view, it has long been known that lysine plays a role in bone metabolism by facilitating calcium absorption in the intestines (4).

A good intake of calcium helps to maintain normal bones and teeth, particularly in growing children.

In combination with vitamin D, it also helps to reduce bone demineralisation in post-menopausal women at risk of osteoporotic fractures (due to osteoporosis).

In fact, research has shown that the combination of lysine and calcium could improve calcium absorption in the bones, while limiting its loss (5).

Support for the immune system

Lysine is also involved in various immune processes.

In particular, it is thought to play a part in the proper functioning of lymphocytes and in the body's defence against microbes, viruses and allergens.

According to some studies, in association with arginine, it could also reduce the production of cortisol (6), a hormone produced in the event of stress and anxiety, which has an immunosuppressive effect (in other words, it reduces the immune defences).

Potential benefits of lysine against herpes

Lysine is also being studied for its potential properties in the fight against the herpes simplex virus (HSV), which is responsible in particular for cold sores (7).

In our bodies, lysine competes with arginine, an amino acid that the virus needs to replicate. So, by increasing lysine intake and reducing arginine intake, we could theoretically limit outbreaks of herpes.

Several studies have suggested that lysine supplementation at a dose of 1 to 3 g/day can reduce the frequency, duration and severity of herpes outbreaks (8).

Targeted supplementation of lysine intake

Although lysine is present in many foods rich in animal or plant proteins, some people may have inadequate intakes or increased needs.

This may, for example, be the case for people following a vegetarian or vegan diet, if they do not pay sufficient attention to their nutritional balance. It is also the case if the diet is unbalanced.

Individuals undergoing periods of intense fatigue, high stress, convalescence or high levels of physical activity may also have higher lysine requirements.

In these situations, lysine supplementation can be a useful addition to the diet, to support the body's specific needs.

Using a quality lysine supplement ensures a targeted intake of this nutrient, with a clearly defined daily dose. As such, it offers more precise intakes than food alone.

• Discover L-Lysine food supplement in vegetarian capsules, containing the amino acid in its natural form.