Carnitine plays crucial role in energy production esp for the heart, fueling mitochondria (cell furnaces). Highest food source? Only animal food, especially red meat; lamb and beef are best. (Redder the L Carnitine Liquid 3300 mg Converts Fat to Clean Energy for Workouts Carbamide Forte Foods High in L Carnitine for Energy and Health Marnys Is L carnitine completely useless? No, while oral l carnitine has minimal effect, acetyle L carnitine form is generally more bioavailable, it may not be show a drastic change, but it does help