Acetyl L-Carnitine is the much more efficiently absorbed form of L-Carnitine, a natural amino acid found in meats and dairy products that plays a vital role in the metabolism of fats to energy. ALC is great for replenishing energy stores post workout. Studies have shown a positive impact on immune function, testosterone regulation, mood enhancement and mental alertness. Anti-aging studies have shown a significant increase in myocellular energy production and healthy cardiovascular function.