Lysine is one of the nine essential amino acids. Amino acids are the building blocks of protein and in total, there are 20 different types. Most of these are manufactured by the body - but nine cannot be and therefore must be consumed in the diet. These nine are called ‘essential’ amino acids and include lysine.
The body requires lysine for the production of proteins, hormones and enzymes. It also plays a role in calcium absorption, the healthy functioning of the immune system and energy production.
Foods that contain all nine essential amino acids are called complete protein foods. These include all animal-based foods such as meat, fish, eggs and dairy products. Plant-based complete protein foods include the grains quinoa and buckwheat, the algae spirulina and soya and soya products such as tofu.