Amino Acid
L-Carnitine Fumarate
Also known as: L-carnitine, LCAF, carnitine fumarate, levocarnitine fumarate
L-carnitine is a compound synthesized from amino acids that facilitates the transport of long-chain fatty acids into mitochondria for energy production. L-carnitine fumarate is a salt form that may have improved bioavailability compared to base L-carnitine.
Daily target & upper limit
1000 mg / dayL-Carnitine Fumarate has an established daily reference intake. See best forms, label synonyms, upper-limit warnings, and top-scoring supplements:
L-Carnitine Fumarate dosage reference →Primary uses
- Energy metabolism and endurance performance
- Fatty acid oxidation support
- Exercise recovery
- Cardiovascular health
How it works
- Transports long-chain fatty acids across the inner mitochondrial membrane (CPT I system) for β-oxidation
- Enhances cellular energy production from fat metabolism
- May improve exercise capacity and reduce fatigue
Dosage
- Typical range
- 2,000–4,000 mg daily
- Timing
- Split into 2–3 doses; pre-workout timing may be beneficial for performance studies
- With food
- Can be taken with or without food; may improve absorption with carbohydrates and protein
- Duration
- Studies typically assess benefits after 2–4 weeks of consistent use; effects may increase with longer duration
- Special populations
- Vegetarians and vegans may benefit most as carnitine is primarily dietary in origin. Dose adjustments may be needed in renal disease; consult healthcare provider.
Forms
- Powder· 70/100
- Capsule· 70/100
- Liquid· 70/100
- Tablet· 70/100
Safety
Common side effects
- Fishy body odor (due to TMAO production)
- Nausea
- Abdominal discomfort
- Diarrhea
Contraindications
- Seizure disorders (historical concern; current evidence is inconclusive)
- Advanced kidney disease (risk of carnitine accumulation)
- Hypersensitivity to carnitine or fumaric acid components
Products containing L-Carnitine Fumarate
Top-scoring supplements in our catalog that list L-Carnitine Fumarate on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.
Evidence notes
L-carnitine has moderate-to-good evidence for improving endurance performance and fatty acid oxidation in trained athletes and certain clinical populations. The fumarate form offers no additional advantage over standard L-carnitine based on current evidence, but the salt may improve absorption.
Grade B: Some human trials support key claims; further confirmation needed.
Cited research for L-Carnitine Fumarate
Clinical studies referenced across Formulate guides that mention l-carnitine fumarate. Each links to the full study page with PubMed source + the guides that cite it.
- Sima AA, Calvani M, Mehra M, Amato A (2005)Diabetes Care
Acetyl-L-carnitine for the treatment of diabetic peripheral neuropathy: a long-term, randomised, double-blind, placebo-controlled study
- Montgomery SA, Thal LJ, Amrein R (2003)International Clinical Psychopharmacology
Acetyl-L-carnitine for the treatment of mild cognitive impairment and mild Alzheimer's disease: a meta-analysis of clinical trials
Related in Amino Acid
Check a full stack
Formulate's free interaction checker lets you paste in any combination of supplements and medications at once — every pairing flags severity, timing, and cited evidence.
Open the checkerMedical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.