Acetyl L carnitine, also known as ALC, is a molecule made up of acetic acid and L carnitine bound together. Acetyl L carnitine is a molecule that occurs naturally in the human brain, kidney, and liver and is also marketed today as a dietary supplement. Ongoing research has shown that the acetyl component of L carntine plays a key role in the production of a major neurotransmitter, acetylcholine, which is responsible for proper brain and nerve cell function, the part that includes memory.