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L-Carnitine

amino acids

L-Carnitine is a naturally occurring amino acid derivative that plays a crucial role in transporting long-chain fatty acids into mitochondria for energy production. It is synthesised in the body from lysine and methionine, and is also found in animal products, making deficiency rare in those consuming adequate protein.

Benefits

Enhanced fat oxidation and energy production
Improved exercise performance and endurance
Reduced muscle fatigue and recovery time
Support for cardiovascular health
Cognitive function and mental clarity

Dosage

Typical Dose

2-4 grams per day

Upper Limit

6 grams per day

Timing

With meals, or pre-workout for performance benefits

Forms & Bioavailability

L-Carnitine L-Tartrate

High absorption, rapidly absorbed, preferred for acute performance benefits

Acetyl-L-Carnitine (ALCAR)

Highly bioavailable, crosses blood-brain barrier, better for cognitive support

Propionyl-L-Carnitine

Good absorption, supports vascular function

Side Effects

Fishy body odour (due to trimethylamine metabolism)
Mild nausea or stomach upset
Muscle weakness in susceptible individuals
Insomnia or restlessness with high doses

Interactions

May enhance effects of anticoagulants
Possible interaction with thyroid medications
Caution with diabetic medications affecting glucose metabolism

Research Summary

Research demonstrates that L-Carnitine supplementation can improve aerobic exercise performance and fat oxidation, particularly in those with low baseline levels. Studies on cognitive function, particularly with ALCAR, show promise for age-related cognitive decline and neurological health. However, evidence for fat loss is mixed and most effective when combined with exercise and caloric restriction.

Where to Buy L-Carnitine

We recommend buying from reputable retailers. Check reviews and third-party testing.

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Disclaimer: This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement, especially if you have existing health conditions or take medication.