Alpha-GPC
L-Alpha glycerylphosphorylcholine
TL;DR
Alpha-GPC is a choline source that crosses into the brain, used at 300–600 mg for acetylcholine support, and at 600 mg pre-workout for power output.
Ideal For
- Older adults with cognitive complaints
- Strength and power athletes
- People on low-choline diets, particularly those eating little egg or liver
Avoid If
- You have established cardiovascular disease and are concerned about TMAO
- You are pregnant or breastfeeding
- You have bipolar disorder — cholinergic agents may worsen depressive phases
Frequently Asked Questions
Overview
Alpha-glycerylphosphorylcholine delivers about 40% choline by weight in a form that crosses the blood-brain barrier efficiently, where it feeds acetylcholine synthesis. It is a prescription cognitive drug in parts of Europe and a supplement elsewhere, which is why the clinical literature is larger than for most nootropics.
The strongest cognitive evidence is in vascular dementia and post-stroke cognitive impairment, where 1200 mg/day produced measurable improvements in trials, most notably the ASCOMALVA study alongside donepezil. In healthy adults the picture is thinner: small crossover studies report faster reaction times and better attention, but sample sizes are small and replication is limited.
The sports finding is more interesting than most people expect. Doses of 600 mg taken 30-60 minutes before training have repeatedly improved isometric strength, vertical jump power and growth hormone response in small trials. The mechanism is plausible — acetylcholine drives neuromuscular transmission — and the effect sizes are modest but consistent. One caution: choline is converted by gut bacteria to TMAO, and a 2021 analysis raised questions about alpha-GPC and cardiovascular risk in observational data.
How It Works
- Delivers bioavailable choline across the blood-brain barrier for acetylcholine synthesis
- Supports neuromuscular transmission at the motor endplate
- Provides choline for phosphatidylcholine, a structural membrane phospholipid
- Transiently increases growth hormone release after dosing
- Supports cholinergic signalling implicated in attention and memory encoding
Quick Facts
- Highly bioavailable choline source
- Enhances acetylcholine synthesis
- Supports cognitive performance
- May increase growth hormone
- Athletic performance benefits
Benefits & Outcomes
Acetylcholine Enhancement
Alpha-GPC is one of the more reliable oral choline sources for raising brain acetylcholine availability.
Cognitive Function
Most positive cognitive data comes from older European trials in dementia and stroke patients rather than healthy adults.
Power Output Enhancement
Small trials suggest an acute boost in force output, but sample sizes are tiny and replication is inconsistent.
Enhanced Memory Formation
Memory benefits in healthy people are not established despite plausible cholinergic mechanisms.
Health Concerns Addressed
No linked health concerns yet.
Supporting Research9 studies
Activity of Choline Alphoscerate on Adult-Onset Cognitive Dysfunctions: A Systematic Review and Meta-Analysis
Sagaro GG, Traini E, Amenta F
We found significant effects of α-GPC in combination with donepezil on cognition [4 RCTs, mean difference (MD):1.72, 95% confidence interval (CI): 0.20 to 3.25].
Cognitive improvement in mild to moderate Alzheimer's dementia after treatment with the acetylcholine precursor choline alfoscerate: a multicenter, double-blind, randomized, placebo-controlled trial
De Jesus Moreno Moreno M
Cognitive improvement in mild to moderate Alzheimer's dementia after treatment with the acetylcholine precursor choline alfoscerate.
Choline-Containing Phospholipids in Stroke Treatment: A Systematic Review and Meta-Analysis
Sagaro GG, Amenta F
Citicoline did not improve the neurological or functional outcomes in acute stroke patients. In contrast, choline alphoscerate improved neurological function and functional recovery and reduced dependency in stroke patients.
The effect of 6 days of alpha glycerylphosphorylcholine on isometric strength
Bellar D, LeBlanc NR, Campbell B
The effect of 6 days of alpha glycerylphosphorylcholine on isometric strength.
Acute Alpha-Glycerylphosphorylcholine Supplementation Enhances Cognitive Performance in Healthy Men
Kerksick CM
No significant differences between groups were found for the Flanker and N-Back assessments... No group differences were realized for visual analog scales, physical performance, or growth hormone.
Evaluation of the effects of two doses of alpha glycerylphosphorylcholine on physical and psychomotor performance
Marcus L, Soileau J, Judge LW +1 more
Evaluation of the effects of two doses of alpha glycerylphosphorylcholine on physical and psychomotor performance.
Comparative study of choline alfoscerate as a combination therapy with donepezil: A mixed double-blind randomized controlled and open-label observation trial
Lee W, Kim M
Choline alfoscerate exhibits additional cognitive improvement in both cognitive and noncognitive domains, supporting the findings of the ASCOMALVA trial.
Volume Analysis of Brain Cognitive Areas in Alzheimer's Disease: Interim 3-Year Results from the ASCOMALVA Trial
Traini E, Carotenuto A, Fasanaro AM +1 more
In the D + CA group (n = 29) the gray matter atrophy was less pronounced compared to the D + P group in frontal and temporal lobes, hippocampus, and amygdala.
Effects of branched chain amino acids, l-citrulline, and alpha-glycerylphosphorylcholine supplementation on exercise performance in trained cyclists: a randomized crossover trial
Harrington RN
There was a significant increase (p = .003) in peak power in the 20 km TT... There was no significant improvement in time to completion, average power, OMNI rating of perceived exertion, or VAS responses on perceived exertion in the TT test.
Safety Information
Potential Side Effects
Headache is the most common complaint, followed by nausea, heartburn and insomnia if taken late. Some report a feeling of mental pressure at higher doses, which usually resolves on dose reduction.
Contraindications
Caution in bipolar depression, where increased cholinergic tone may aggravate symptoms. Discuss with a clinician if you have significant cardiovascular disease, given the TMAO conversion pathway.
Drug Interactions
- Anticholinergic medications — opposing pharmacology
- Cholinesterase inhibitors such as donepezil — additive cholinergic effect, studied deliberately in trials
- Scopolamine — alpha-GPC has been used to counter its cognitive effects
Pregnancy & Breastfeeding
Pregnancy: insufficient_data
Breastfeeding: insufficient_data
Dosage Guidelines
Dosage Used in Studies
300-600 mg
Best Time to Take
Morning for cognitive use; 30-60 minutes pre-training for performance use
Best Form
Encapsulated alpha-GPC, because the raw powder absorbs moisture from the air within minutes
Bioavailability
Highly bioavailable choline source. Crosses blood-brain barrier effectively. Increases acetylcholine synthesis. More bioavailable than choline bitartrate.
Forms Compared
Alpha-GPC 50% powder
Alpha-GPC capsules
Citicoline (CDP-choline)
Food & Timing
With or without food
Medical Disclaimer
The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.
Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.