Acetyl-L-Carnitine is possibly the most effective form of carnitine, a quaternary ammonium compound involved in metabolism, in the body as related to the brain. It is an amino acid, a protein-building block, that may help prevent age-related mental decline and improve markers of learning. It could possibly help reverse the decline in brain function associated with Alzheimer’s disease and may possess benefits for general brain function in older adults who do not have Alzheimer’s or other brain conditions.