Carnitine is synthesized in the body from the essential
amino acid lysine. The conversion of lysine to carnitine in all cells of the
body is dependent upon adequate vitamin C levels. It has been estimated that
about 0.1 percent of the dietary lysine is converted to carnitine in the body.
Carnitine is not found in a vegetable-based diet; it is only found in animal
products. Therefore, vegetarians who may consume a lysine-deprived diet may
have insufficient amounts of carnitine. Animals fed a wheat gluten diet low in
lysine and carnitine have significantly lower levels of carnitine in their
hearts and skeletal muscles.
Recently, medical studies in Japan and Europe have
indicated that carnitine supplementation can help lower triglycerides in
individuals with elevated blood fats. Doses used are between 400 and 2,000 mg
per day of L-carnitine.
D,L-carnitine (the synthetic derivative) has also been
found useful in lowering triglycerides, but may have a more significant problem
with liver toxicity associated its excessive use.
Preliminary reports indicate that carnitine may be useful
for extending endurance in athletes who are engaged in long-term exercise.
Carnitine has also been used to treat acid buildup in the blood of diabetics