Cognitive / Nootropics
Acetyl-L-Carnitine (ALCAR)
Also known as: ALCAR · Acetylcarnitine
The acetylated form of L-carnitine that crosses the blood-brain barrier. Donates acetyl groups for acetylcholine synthesis, supports mitochondrial function in neurons, and has established evidence for diabetic neuropathy.
Effective Dose
500–2000mg / day
per clinical evidence
Evidence Level
Moderate
Cognitive / Nootropics
Mechanism
Acetyl group donation for ACh synthesis, mitochondrial fuel transport, neuroprotection
primary action
Best For
Cognitive energy
Neuropathy, Depression, Anti-ageing
This profile is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications.
What Is Acetyl-L-Carnitine (ALCAR)?
Acetyl-L-carnitine is a form of carnitine where an acetyl group is attached. Unlike standard L-carnitine, ALCAR readily crosses the blood-brain barrier. The acetyl group can be donated to CoA to form acetyl-CoA (mitochondrial fuel) or to choline to form acetylcholine. This dual role — neuronal energy and neurotransmitter synthesis — underlies its cognitive benefits.
How It Works: The Science
In neurons, ALCAR donates its acetyl group to acetyl-CoA in the mitochondrial matrix, supporting the TCA cycle and ATP synthesis in high-demand neural tissue. The acetyl group also donates to choline acetyltransferase (ChAT), increasing ACh synthesis. ALCAR reduces oxidative stress in mitochondria and supports NGF expression, providing a degree of neuroprotection.
Primary Mechanism
Acetyl group donation for ACh synthesis, mitochondrial fuel transport, neuroprotection
Evidence-Based Benefits
Dosage Guide
Effective Dose
500–2000mg / day
500–2000mg/day in divided doses. For neuropathy: 1500–3000mg/day (clinical trials). For cognitive use: 500–1000mg twice daily. Take in the morning — stimulating effect may disrupt sleep.
Safety Profile & Side Effects
Generally safe. Mild fishy body odour at high doses (TMAO metabolism). Avoid in thyroid conditions (may increase thyroid hormone sensitivity). Not the same as L-carnitine for exercise fat oxidation.
Who Should (and Shouldn't) Take It
Cognitively focused individuals, those with diabetic neuropathy, older adults with age-related cognitive decline, and those experiencing depression or brain fog.
Frequently Asked Questions
Related Ingredients
Medical Disclaimer
Ingredient profiles are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications. Full disclaimer →