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    L-Carnitine

    With meals

    L-Carnitine is a naturally occurring amino acid derivative synthesized from lysine and methionine, with the highest dietary concentrations found in red meat and dairy products. It plays a central role in cellular energy metabolism by shuttling long-chain fatty acids into the mitochondria where they are oxidized for fuel. It is available in several supplemental forms, with acetyl-L-carnitine (ALCAR) being the most bioavailable and widely studied.

    Andrew Huberman
    Andrew HubermanTakes it
    Research Evidence
    Supports cognitive function and neuroprotection via acetyl-L-carnitine form
    Limited
    May improve cardiovascular risk markers including CRP and cholesterol ratios
    Moderate
    Improves sperm motility, count, and overall male fertility markers
    Moderate
    Enhances exercise recovery and reduces markers of muscle damage
    Moderate
    Supports mitochondrial fatty acid oxidation and cellular energy production
    Strong
    Source: Examine.com

    Expert Evidence

    22 references from 4 experts

    “I'm a fan of L-acetyl-L-carnitine lately. I've been kind of experimenting with that a little bit, and I take it every day.”

    Psychedelics for Treating Mental Disorders | Dr. Matthew Johnson

    1:46:04
    Safety & Cautions

    Side Effects

    • Fishy body odor at higher doses
    • Nausea or stomach discomfort
    • Diarrhea
    • Restlessness or difficulty sleeping if taken late in the day
    L-Carnitine is generally well-tolerated at doses up to 2,000 mg per day. Individuals with thyroid conditions should consult a physician, as carnitine may interfere with thyroid hormone action, and those with a history of seizures should exercise caution with high doses.
    Pairs Well With
    Alpha-GPCCoQ10Omega-3 Fatty Acids (EPA)Alpha Lipoic Acid