Acetyl-L-carnitine, an amino acid derivative, promotes youthful cellular energy metabolism and supports mood and nervous system well-being. But levels of the compound it is made from, L-carnitine, decline with age. Acetyl-L-carnitine encourages the movement of fatty acids into mitochondria, where they can be burned as fuel to produce energy. Thus, acetyl-L-carnitine supports mitochondrial energy requirements, helping to provide whole-body energy. Supplementation with acetyl-L-carnitine has been shown to support energy-intensive body systems such as the nervous system and cardiovascular system. It also helps support against the age-related increase in oxidative stress and the decrease in mitochondrial efficiency that occurs with advancing years. Acetyl-L-carnitine has wide-ranging benefits for nervous system wellness, including the central and peripheral nervous systems and cognitive health, as well as promoting positive mood. It has been shown to promote peripheral nervous system comfort and to support healthy mood, energy and overall well-being.