Hair growth is determined by a number of factors: genetics, nutrition, hair care and general health among others. Enzymes are proteins needed to maintain various bodily functions. Certain essential enzymes are known to stimulate hair growth.

Cysteine is the most common amino acid in hair, according to Haircare information. Cysteine contains sulfur molecules, which can create chemical bonds to strengthen hair.

An important enzyme found in fish, meat and vegetables, Coenzyme Q10 improves scalp circulation and increases tissue oxygenation. Both these functions help to stimulate hair growth.

Bromelain is a popular plant enzyme found in many hair care products. It is derived from the common pineapple plant and is commonly used to promote hair growth.

According to PubMed, Substance P can induce significant hair growth from the telogen (resting stage of hair cycle) to the anagen (active growth) phase. Substance P is a protein found in the brain and spinal cord.

Biotin is a coenzyme necessary for the metabolism of fats and amino acids and it also promotes cell growth. It is often used for strengthening hair and promoting hair growth.

Always consult your physician before using supplements containing hair-growth enzymes.