L-Carnitine
Shuttles fat into cells for burning
- Fat Loss
- Energy/Athletic Performance
- Recovery
- Mitochondrial Function
- Cardiovascular Health
Individuals with seizure disorders should use with caution and medical supervision Long-term supplementation may increase TMAO levels - cardiovascular implications still being studied May interfere with thyroid hormone action - monitor if on thyroid replacement therapy Use caution in patients with kidney disease - requires dose adjustment and monitoring
Mechanism of Action
L-Carnitine is an endogenous amino acid derivative that transports long-chain fatty acids across the inner mitochondrial membrane via the carnitine palmitoyltransferase (CPT) system, enabling beta-oxidation for ATP production. It facilitates the conversion of fatty acyl-CoA to fatty acylcarnitine, which can traverse the mitochondrial membrane, then reconverts to fatty acyl-CoA in the matrix for oxidation. This transport function is essential because long-chain fatty acids cannot passively cross the inner mitochondrial membrane without carnitine shuttling. Key Pathways: Carnitine shuttle system (CPT-1, CACT, CPT-2), Mitochondrial fatty acid beta-oxidation, Cellular energy metabolism and ATP production, OCTN2-mediated cellular carnitine uptake By facilitating fatty acid transport into mitochondria, L-carnitine supports the use of fat as fuel during exercise and at rest, which underlies its applications in fat loss and athletic performance. Enhanced mitochondrial fatty acid oxidation improves cardiac energy metabolism, as demonstrated in myocarditis models where levocarnitine increased ATP production and reduced oxidative stress. The compound also helps buffer acyl-CoA accumulation, supporting cellular energy homeostasis during metabolic stress.
Common Dose Reference Ranges
Educational reference ranges only — discuss actual dosing with a qualified healthcare provider.
Full L-Carnitine protocols — frequency, timing, cycle length, reconstitution & research
- Gastrointestinal disturbances (nausea, vomiting, diarrhea, abdominal cramps)
- Fishy body odor
- TMAO production (trimethylamine N-oxide)
- Mild headache
- Insomnia or restlessness
- Seizures in susceptible individuals
- Muscle weakness in uremic patients
- Drug interactions with thyroid hormones