About L-Carnitine

Mechanism of Action: A naturally occurring amino acid derivative that transports long-chain fatty acids into mitochondria for β-oxidation, supporting cellular energy production.

Indications & Off-Label Uses: FDA-approved as a prescription for primary and secondary carnitine deficiency. Off-label uses include enhancing exercise performance, fat metabolism, cardiovascular support, longevity and energy optimization. Evidence for these uses is mixed.

FDA Status: Approved for carnitine deficiency; other uses are off-label.

Clinical Evidence: Studies show modest improvements in exercise endurance, fatigue reduction and some cardiometabolic benefits. Effects in healthy adults for performance or anti-aging are less robust.

Safety & Monitoring: Generally well tolerated; adverse effects may include nausea, diarrhea, and mild “fishy” odor. High doses may rarely increase seizure risk in susceptible individuals.