Nutrient - Lysine - essential amino acid

By Jenny Bodenham BA(Hons) DipION MBANT

What is Lysine?

Lysine is one of the essential amino acids that the body needs for building protein in the body. The term “essential”, when talking about amino acids, means that the body cannot create it and it must, therefore, be obtained from the diet or supplements. 

Functions

Immune Support

Lysine  assists in  the production of antibodies, hormones and enzymes in the body. Studies have shown that lysine is an important amino acid in the health maintenance of people who suffer from shingles, cold sores and genital herpes.

Cardiovascular Support

Lysine is involved in the production of carnitine, which is an important heart nutrient that transports fatty acids to the cells for conversion into energy and helps maintain healthy cholesterol and triglyceride levels. Lysine is also important for the integrity of tissue in the artery walls and binds to the lipoprotein A, which has a negative effect on arteries. 

Skeletal Health

Lysine plays a role in the absorption of calcium, helping to improve calcium absorption in the gut and preventing loss of calcium in the urine. Lysine deficiency is associated with increased excretion of calcium, which can result in low bone density. Lysine also assists the formation of collagen, an important component of connective tissue and bones.

Detoxification

Lysine bonds to the heavy metal lead, aiding its removal from the body.

Depletion

Vegetarians and vegans can be at risk from lysine deficiency. Deficiency signs may include low energy, loss of appetite, hair loss, delayed growth and anaemia.

Lysine levels can be depleted by:

• Excess arginine in the diet (found in foods including beans, nuts and seeds, chocolate, beef, pork, turkey and mackerel) may lower levels of lysine.
• A diet high in cereals and baked goods, which contain simple sugars. This is because lysine and sugar bind together in caramelisation of sugars at high temperatures.

Food sources

Protein-rich foods are good sources of lysine. These include:

• Meat (specifically red meat, lamb, pork and poultry).
• Cheese (particularly Parmesan) and milk.
• Fish (such as cod and sardines).
• Eggs.
• Beans, peas and lentils.
• Brewer’s yeast.
• Potatoes.

Note: Lysine supplements should not be taken indefinitely while reducing arginine-high foods, as this may cause an arginine imbalance. 

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