Also indexed as: Propionyl-L-Carnitine
L-carnitine is made in the body from the amino
acids lysine and methionine, and is needed to release energy from fat. It transports fatty acids into mitochondria,
the powerhouses of cells. In infancy, and in situations of high energy needs, such as pregnancy and breast-feeding, the need for L-carnitine
can exceed production by the body. Therefore, L-carnitine is considered a "conditionally
essential" nutrient.1
Where is it found?
Dairy and red meat contain the greatest amounts of carnitine.
Therefore, people who have a limited intake of meat and dairy products tend to have lower
L-carnitine intakes.
L-carnitine has been used
in connection with the following conditions (refer to the individual
health concern for complete information):
Who is likely to be deficient?
Carnitine deficiencies are rare, even in strict vegetarians, because the body produces carnitine
relatively easily.
Rare genetic diseases can cause a carnitine deficiency. Also, deficiencies are occasionally
associated with other diseases, such as
diabetes and cirrhosis.2
3 Among people with diabetes, carnitine deficiency is more likely to be found in persons
experiencing complications of diabetes (such as
retinopathy, hyperlipidemia, or neuropathy), suggesting that carnitine deficiency may play
a role in the development of these complications.4 A carnitine deficiency can also
result from oxygen deprivation which can occur in some heart conditions. In Italy, L-carnitine is prescribed
for heart failure, heart arrhythmias, angina, and lack of oxygen to the
heart.5
How much is usually taken?
Most people do not need carnitine supplements. For therapeutic use, typical amounts are
1–3 grams per day.
It remains unclear whether the propionyl-L-carnitine form of carnitine used in congestive heart failure research has greater benefits
than the L-carnitine form, since limited research in both animals and humans with the more
common L-carnitine has also shown very promising effects.6
Are there any side effects or interactions?
L-carnitine has not been consistently linked with any toxicity.
The body needs lysine, methionine, vitamin C, iron,
niacin, and vitamin B6 to produce
carnitine.
Are there any drug
interactions?
Certain medicines may interact with L-carnitine. Refer to drug interactions for a list of those medicines.
References:1. Giovannini M, Agostoni C, Salari PC. Is carnitine essential in
children? J Int Med Res 1991;19:88-102.
2. Dipalma JR. Carnitine deficiency. Am Fam Physician
1988;38:243–51.
3. Kendler BS. Carnitine: an overview of its role in preventive medicine.
Prev Med 1986;15:373–90.
4. Tamamogullari N, Silig Y, Icagasioglu S, Atalay A. Carnitine
deficiency in diabetes mellitus complications. J Diabetes Complications
1999;13:251–3.
5. Del Favero A. Carnitine and gangliosides. Lancet 1988;2:337
[letter].
6. Kobayashi A, Masumura Y, Yamazaki N. L-carnitine treatment for
congestive heart failure—experimental and clinical study. Jpn Circ J
1992;56:86–94.