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. Unlock Peak Performance & Fertility with L Carnitine! Did you know that injectable L Carnitine is a game changer compared to oral supplements? While oral L Carnitine has low bioavailability (only ~14 18% L Carnitine Liquid 16 fl oz Meet L Carnitine a naturally occurring amino acid that plays a key role in helping the body convert fat into usable energy. It works by transporting fatty acids into your cells to L Carnitine Force Factor