Acetyl L-Carnitine is an altered form of the amino acid, L-Carnitine, and is one of the most researched forms of carnitine. Furthermore, evidence suggests that the absorption from the small intestine of the acetyl form of this particular amino acid is enhanced.

Carnitine is an important amino acid made in the body from lysine, in the presence of vitamin C, and is mainly found in animal based foods. It is best known for its role in supporting mitochondrial health since it is responsible for transporting fatty acid chains to the mitochondria within cells, where they are oxidised to produce energy. Carnitine is also in charge of removing waste products from the mitochondria. L-Carnitine and in particular, Acetyl L-Carnitine, is widely recommended by practitioners.