StackTerminal.Health

BETA

L-Carnitine / Acetyl-L-Carnitine (ALCAR)

L-Carnitine is a fatty acid transporter essential for mitochondrial energy production; its acetylated form ALCAR additionally crosses the blood-brain barrier, acting as an acetylcholine precursor with evidence supporting cognitive function in aging & cardiovascular-metabolic risk reduction.

cognitivemetaboliclongevitycardiovascularmitochondrial
Evidence last reviewed: 04 Apr 2026
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Biomarkers studied
Outcomes directly measured across the evidence records below
Cardiovascular
Blood PressureHDL CholesterolTriglycerides
Metabolic
Blood Glucose
Cognitive
Cognitive Function
Evidence
3 records
Depressive symptoms
Adults with depressive disorders, including older adultssystematic review and meta-analysis of RCTs
PUBMEDModerate

Systematic review & meta-analysis found ALCAR significantly reduced depressive symptoms versus placebo or active comparators, with particularly pronounced effects in older adults; effect comparable to antidepressants but with a superior tolerability profile.

Dose: 2000 mgDuration: 8–24 weeks
Cognitive function in mild cognitive impairment & Alzheimer's disease
Adults with mild cognitive impairment or mild Alzheimer's diseasemeta-analysis of RCTs
PUBMEDModerate

Meta-analysis of 21 RCTs (n=1,204 evaluable) found a significant advantage for ALCAR versus placebo on both clinical scales & psychometric tests (ES=0.201, 95% CI 0.107–0.295 for integrated summary effect), with benefits emerging at 3 months & increasing over time at doses of 1.5–3.0 g/day.

Dose: 2000 mgDuration: 3–12 months
Metabolic syndrome biomarkers (waist circumference, blood pressure, lipids, glycemia)
Adults with metabolic syndrome or cardiovascular risk factorssystematic review and meta-analysis of RCTs
PUBMEDModerate

Meta-analysis of 9 RCTs found L-carnitine (0.75–3 g/day, 8–24 weeks) significantly reduced waist circumference & systolic blood pressure; at doses >1 g/day, fasting blood sugar, triglycerides, & HDL-cholesterol were also significantly improved.

Dose: 1500 mgDuration: 8–24 weeks
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Stacks containing L-Carnitine / Acetyl-L-Carnitine (ALCAR)

Public community stacks that include this ingredient.

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mens-healthfertilitytestosterone

Male factor infertility accounts for ~50% of cases & is largely driven by oxidative stress, micronutrient deficiency, & suboptimal testosterone. Ashwagandha has RCT evidence for significantly improving sperm concentration, motility, & testosterone. L-carnitine is the most evidence-backed intervention for sperm motility. CoQ10 & selenium reduce seminal oxidative damage, while zinc is essential for spermatogenesis & androgen synthesis.

Ashwagandha
600mg
L-Carnitine / Acetyl-L-Carnitine (ALCAR)
2000mg
Coenzyme Q10
300mg
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