Lysine is an essential amino acid which, among other things, has antiviral properties and is a building block of collagen. A deficiency of lysine leads to growth disorders and reduced immune function.

What are the functions of lysine?

The antiviral function in the body
Lysine has antiviral properties. It counteracts the amino acid arginine, which is needed for the division of the herpes virus. Also, lysine is involved in the formation of antibodies.

Involvement of lysine in carnitine synthesis
Lysine is involved in the endogenous synthesis of carnitine. Carnitine plays an important role in energy metabolism during the transport of fatty acids.

Important component in bone metabolism
On the one hand, lysine appears to improve calcium absorption and, on the other, to optimize the activity of the bone-building cells known as osteoblasts.

An amino acid with a building block function
The most important function of lysine is to act as a protein building block and as a component of collagen (together with L-glycine and L-proline).

Lack of sufficient lysine intake in a vegan diet.

People living vegan should pay attention to an adequate intake of lysine, since lysine is found in lower amounts in plant sources than in animal sources.

Dosages during pregnancy

The administration of therapeutic doses of lysine should be avoided in pregnant women due to insufficient data and thus also for safety reasons.

Lysine in food

100 g contain:

Parmesan     3,0 mg            tuna   2,2 mg 
pork   2,2 mg   soybeans     1,9 mg
oatmeal   0,5 mg       


Good to know about lysine

  • The daily requirement of lysine is 38 mg per kilogram of body weight
  • A person weighing 70 kg requires 2.7 g/day
  • Plant proteins have lower levels of lysine than animal proteins
  • Lysine can help with fever blisters

When is lysine used?

Herpes labialis: Lysine supplements are used to reduce the recurrence of herpes labialis infections and the resulting cold sores. It is believed that lysine can inhibit the reproduction of the virus. Dosage: 3 g of lysine per day is recommended for acute herpes infection, and 1.5 g for prophylaxis.

Deficiency symptoms

  • Fever blisters (herpes simplex labialis)
  • susceptibility to infections
  • low carnitine blood levels

Why does L-lysine help with cold sores?

Lysine plays an important role in cell division and growth. As early as 1952, it was found that a high lysine concentration reduces the growth of the herpes simplex virus. Subsequent studies describe that lysine can reduce or shorten a repeated occurrence. The counterpart arginine, however, promotes the growth of herpes simplex viruses. By taking L-lysine - independently of meals - symptoms of cold sores can be reduced, or the outbreak can even be avoided.

Products with Lysine...

L-Lysine 500 mg

The insider tip for every season.

L-lysine is an essential amino acid, which means that it cannot be produced by the body itself and must therefore be supplied with food. L-lysine is the counterpart of the amino acid…

L-Lysine 500 mg