L-Carnitine
Metabolic Supplement / supply Human trials
Also called Levocarnitine
Not a peptide — a small molecule the body makes from lysine and methionine. It is the shuttle that carries long-chain fatty acids into mitochondria to be burned, which is why it turns up in every fat-loss and endurance discussion.
Why people take it
What studies report
- Essential carrier in the carnitine shuttle, well established biochemistry
- Clear benefit in genuine carnitine deficiency
- Small or inconsistent effects on fat loss and performance in people who are not deficient
In practice Unapproved use
- Injected in bodybuilding circles during fat loss phases
- Taken orally by endurance athletes
Reported real-world use, not evidence and not a recommendation.
Worth knowing: Supplementing when you are not deficient has repeatedly shown little effect. Oral carnitine is also converted by gut bacteria into TMAO, a metabolite linked in observational work to cardiovascular risk.
Status: Approved as a prescription medicine (Carnitor) for carnitine deficiency; otherwise a supplement.
- Route
- Oral, or injected in off-label use
- Formula
- C7H15NO3
- Molecular weight
- 161.20 g/mol
- CAS
- 541-15-1
- Available as
- 600 mg/mL
Educational information only. Nothing here is medical advice, a dosing protocol, or a recommendation to use any compound. Most entries describe substances not approved for human use. Talk to a licensed clinician before acting on anything you read here. How to read these entries.