Healthvit Acetyl L Carnitine (ALCAR) Capsules L carnitine is a naturally occurring amino acid structure that is made in the human brain, liver, and kidneys. L carnitine plays a critical role in energy production, as it converts fat into energy. Comparison of short term and long term effects of peroral L carnitine intake: clinical implications of elevated TMAO levels in cardiovascular complications L Carnitine: Benefits, side effects, and dosage The Role of l Carnitine in Mitochondria, Prevention of Metabolic Inflexibility and Disease Initiation