Supplement Monograph

L-Carnitine

An amino-acid derivative that ferries fatty acids into mitochondria to be burned for energy.


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Where Does It Come From?

L-carnitine is made in the body from the amino acids lysine and methionine, and is obtained from the diet mainly through red meat and dairy.

Indications

L-carnitine is used to support energy and fatigue and exercise recovery, while the acetyl form (ALCAR) is favoured for cognitive support.

Contraindications

L-carnitine is generally safe, but high doses can cause digestive upset and a fishy body odour from TMAO production.

Chemical Description:

L-carnitine is an amino-acid derivative. It exists in several forms, including plain L-carnitine, acetyl-L-carnitine (ALCAR), which is more brain-penetrant, and L-carnitine L-tartrate, which is often used for exercise.

Extractions/Synthesis:

L-carnitine is synthesised within the body from lysine and methionine and is also obtained from animal-source foods such as red meat and dairy.

Pharmacology & Medical Research

L-carnitine has been studied for its role in fatty-acid metabolism and energy production, with additional research into exercise recovery and, for the acetyl form, cognitive support.

Pharmacodynamics:

L-carnitine’s core function is transporting long-chain fatty acids across the mitochondrial membrane for beta-oxidation, the process that turns fat into usable energy.

Synergy:

L-carnitine is often paired with exercise and other energy-supporting nutrients, and ALCAR is sometimes combined with cognitive supplements.