Other name(s):

a,e-diamino-n-caproic acid

General Information

Lysine is an essential amino acid necessary for the synthesis of protein as well as the metabolism of carbohydrates and fatty acids. 

Unsubstantiated claims

Please note that this section reports on claims that have NOT yet been substantiated through scientific studies.

Lysine has been said to slow or stop the growth of viruses and may protect against sexual transmission of herpes virus. It may prevent the recurrence of herpes lesions (cold sores) when taken together with vitamin C and bioflavonoids.

In addition, lysine is believed to improve calcium utilization and aid in bone growth and healing.

It is reported to prevent fatigue and increase stress tolerance.

Recommended intake

Amino acids (AAs) are available as individual AAs or in proprietary AA combinations, as well as part of multi-vitamin formulas, proteins, and food supplements. The forms include tablets, fluids, and powders. However, adequate protein in the diet should provide a sufficient source of all amino acids.

There are no conditions that increase the nutritional requirements for lysine.

Side effects, toxicity, and interactions

The use of a single amino acid supplement may lead to a negative nitrogen balance, decreasing the metabolic efficiency and increasing the workload in the kidneys. In children, taking single amino acid supplements may also harmfully affect growth parameters.

Always avoid taking individual amino acids in high dosage for prolonged periods.

Consult your doctor before taking lysine if you have diabetes or are using blood sugar lowering agents, as well as if you have osteoporosis or are using calcium supplements, as lysine may reduce the absorption of supplemental calcium and decrease urine loss. 

Women who are pregnant or breastfeeding should not use lysine supplements.

Additional information

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