L-carnitine
What it is
Transports long-chain fatty acids into mitochondria for oxidation; theorized to support fat metabolism.
What the evidence says
A 2020 dose-response meta-analysis (Talenezhad et al., 37 RCTs, 2,292 participants) found L-carnitine modestly reduced body weight (-1.21 kg), BMI (-0.24) and fat mass (-2.08 kg), with no significant effect on waist circumference or body-fat percentage. Effects were largely confined to people with overweight/obesity and to studies combined with diet/exercise; restricting to high-quality trials weakened results to body weight only. Overall a small, supportive effect rather than a stand-alone weight-loss agent.
Around 2,000 mg/day, where dose-response modeling suggested the maximal effect in adults.
Educational summary of doses studied — not a recommendation. Talk to a clinician before starting any supplement.
Sources (1)
Educational summary of published research, checked against primary sources and linked inline. Not medical advice; supplements are not FDA-evaluated to treat disease. See our editorial policy.