L-Carnitine
- Effective dose
- 1–3 g
- Evidence
- 3/5· Moderate
Last updated June 1, 2026
What it is
L-carnitine is an amino-acid-derived compound that shuttles long-chain fatty acids into the mitochondria, where they are burned for energy. The body makes it and obtains it from meat, so deficiency is rare in healthy people eating a mixed diet.
Benefits
Supplementation produces a modest reduction in body weight, BMI, and fat mass, with a dose-response analysis suggesting about 2 g/day gives the maximum effect, and trials generally using 1-3 g/day. Effects are most apparent in people with overweight or obesity and alongside diet and exercise.
When to take it
Often taken with a carbohydrate-containing meal to aid uptake; daily consistency over several weeks is needed for measurable effects.
Side effects
Generally well tolerated; higher doses may cause nausea, stomach upset, or a fishy body odor. Long-term high intake has been linked in some research to raised TMAO, a cardiovascular-risk marker.
Sources
Products containing L-Carnitine
No products in our database contain this ingredient yet.