Actyl L Carnitine Therascience L Carnitine Benefits for Fat Burning and How to Use ICONFIT Acetyl L Carnitine is a modified form of carnitine that has the dual benefit of supporting mental fatigue, improving mood levels and alertness as it crosses the blood brain barrier with ease while supporting Did you know L carnitine, a vital amino acid, is naturally produced by your body and found in various foods? While acetyl L carnitine (ALCAR) can be a beneficial supplement for some, most people get