Acetyl-L-Carnitine is a source of carnitine, a naturally occurring amino acid. In the body it is responsible for the transport of fatty acids into the mitochondria (the cell's powerhouses) where they are used to produce the energy rich chemicals that fuel the body. Although carnitine is actively taken up to into cells, different tissues appear to prefer different forms, for example the Myocardium (heart Muscle) prefers propionyl-L-carnitine. Acetyl-L-Carnitine occurs naturally in the human brain. The Acetyl part of the molecule is linked with acetylcholine (a chemical messenger required to transmit nerve impulses) which improves the brains ability to function & communicate with other organs. Acetyl-L-Carnitine appears to be the best form to take for brain health.