Acetyl L Carnitine VS L Carnitine: Which One Is Better? Acetyl L carnitine, ALC, ALCAR molecule. Dietary supplement acetylcarnitine. Molecular model. 3D rendering. Illustration Stock Photo Alamy What Is L Carnitine? L Carnitine Benefits, Dosage & When To take? MYPROTEIN Acetyl L carnitine, ALCAR or ALC, is an acetylated form of L carnitine. It is naturally produced by the human body, and it is available as a dietary s Stock Photo Alamy