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Lysine

Lysine was isolated from the milk protein casein in 1889 and its structure was clarified in 1902. The amino acid lysine is essential for humans. As lysine cannot be produced by the body itself, this amino acid must be ingested in sufficient quantities in the diet. Lysine is a part of many proteins and accordingly has many functions in the body. It contributes to growth, tissue repair, the formation of enzymes, hormones and antibodies as well as collagen synthesis and bone health. Lysine may help to absorb and store calcium. Lysine further maintains nitrogen balance in the body, and it plays an important role in the immune system, with known antiviral capabilities. Lysine may also contribute to the health of the cardiovascular system. As a building block of collagen, lysine is an important component of the blood vessel walls and can thus strengthen the arterial walls.

The main sources of lysine

Lysine is abundant in animal foods, milk and dairy products, eggs and fish. Vegetables, on the other hand, contain little lysine, with the exception of pulses (beans, peas, lentils). With a few exceptions (e.g. buckwheat, rice), nuts and cereals also tend to be low in lysine. Compared to other amino acids, lysine reacts much more sensitively to processing, especially to heating with dry heat (e.g. toasting, roasting).

Typical groups for an increased requirement of lysine

If the immune system is weak, for example in the case of frequently recurring herpes infections, the need for lysine may be increased. Through its involvement in calcium metabolism, lysine can prevent osteoporosis and contribute to its treatment. As lysine is part of collagen and can thus strengthen the vascular walls, orthomolecular physicians also recommend lysine supplements as an accompanying therapy for cardiovascular diseases. There is also evidence that lysine can help to reduce triglycerides and improve recovery after injuries and operations.

However, further studies on the effects of lysine are required.

  • People with herpes infections
  • possibly with osteoporosis
  • possibly for cardiovascular diseases
  • possibly athletes

When lysine is lacking in the body

A lysine deficiency can disrupt all lysine-dependent functions in the body. This affects, for example, growth, nitrogen balance and immune functions. Such deficiencies are mainly known in countries where the diet consists mainly of cereals low in lysine, such as maize.

Can lysine be overdosed or are there side effects?

There are no reports of toxic effects in healthy adults when taking lysine up to a dose of 4 grams per day. At very high doses (15 to 40 g daily), intestinal cramps and diarrhea may occur. In the case of food allergies to milk, wheat or eggs, some experts recommend avoiding lysine.

The daily requirement of lysine

The daily requirement of lysine for healthy adults is 15 mg/kg (milligrams per kilogram) of body weight.

Precautions and warnings

  • Pregnancy and lactation: Not enough is known about the safety of lysine during pregnancy and lactation. For this reason, pregnant and breastfeeding women should avoid lysine to be on the safe side.
  • Kidney disease: There is one report of kidney disease associated with taking lysine supplements. If you suffer from kidney disease, you should consult your doctor before taking lysine.
  • Osteoporosis: The use of lysine in combination with calcium supplements could increase calcium absorption.
  • Lysinuric protein intolerance: Lysine supplementation can cause diarrhea and stomach cramps in children suffering from lysinuric protein intolerance.

Interactions

Care should be taken when combining lysine with the following medications:

Calcium supplements

Lysine can increase the amount of calcium absorbed by the body. Taking calcium in combination with lysine can increase calcium levels in the body. For this reason, you should not take large amounts of calcium at the same time as lysine.