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Agp5.5

Alpha-GPC

Alpha-GPC (L-Alpha Glycerylphosphorylcholine)

A highly bioavailable choline source that supports acetylcholine production for focus, memory, and athletic performance.

mentalperformancecognitionfocusmemoryacetylcholine
5.5/10
30+ studies
Evidence
moderate
Safety
300-600mg daily
Dose
2-8 weeks
Time to Effect
Alpha-GPC 50% powder or capsules
Best Form

Alpha-GPC is one of the most bioavailable forms of choline, efficiently crossing the blood-brain barrier to support acetylcholine synthesis. It's used for cognitive enhancement and has some evidence for power output in athletes. Often paired with racetams in nootropic stacks.

Mechanisms of Action

Acetylcholine Precursor

Provides choline for neurotransmitter synthesis

🧱
Membrane Phospholipids

Supports brain cell membrane structure

💪
Growth Hormone Support

May acutely increase growth hormone

Recommended Dose

300-600mg daily

150mg1200mg

Optimal Timing

  • Morning for cognitive enhancement
  • 30-60 min before workout for performance

Can be taken without food

Best Form

Alpha-GPC 50% powder or capsules

Alternatives: Alpha-GPC 100% (less common), Liquid

Most products are 50% Alpha-GPC (rest is carrier). Hygroscopic (absorbs moisture) so keep dry. Some pre-workouts include it.

Duration

Minimum: 2 weeks

Optimal: 8 weeks

Cycling: Some cycle 5 days on, 2 days off or 4 weeks on, 1 week off to maintain sensitivity

Note: Can be taken with or without food. Morning for cognitive benefits. Pre-workout (300-600mg) for athletic performance.

🎯
Sharper Focus

Improved concentration and mental clarity

1-2 hours
70% of users notice thispositive
📚
Memory Support

Enhanced learning and recall

2-4 weeks
60% of users notice thispositive
💪
Power Output

Possible improvement in explosive power

Acute
45% of users notice thispositive
😣
Headache

Can cause headaches in some, especially at high doses

Same day
20% of users notice thistrade-off
ModerateMax safe dose: Up to 1200mg/day used in studies
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Pregnant/nursing

Choline is important during pregnancy; Alpha-GPC less studied

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Cardiovascular disease

One study suggested possible cardiovascular concerns; more research needed

Who Should NOT Take This

  • History of stroke or TIA (one study raised concerns, needs more research)

Drug Interactions

Anticholinergic drugsmoderate

May counteract anticholinergic effects

Cholinergic drugsmild

Additive cholinergic effects

Possible Side Effects

Headacheuncommon

Tip: Reduce dose; may indicate too much acetylcholine

Fishy body odorrare

Tip: Reduce dose

GI upsetrare

Tip: Take with food

Warnings

  • Headaches may indicate dose is too high
  • One 2021 study raised cardiovascular concerns - more research needed
  • Hygroscopic - keep container sealed
systematic-review
DOI

Parker AG et al.Nutrients (2020)

Alpha-GPC supplementation improved cognitive function in dementia patients and enhanced power output in athletes.
Key Findings:
  • Consistent improvements in cognitive function in dementia and Alzheimer's patients
  • Enhanced power output and growth hormone secretion in athletes
  • 600-1200 mg/day was the effective dose range across studies
review
DOI

Traini E et al.Aging Clinical and Experimental Research (2018)

Alpha-GPC is the most effective choline donor for brain acetylcholine synthesis among oral choline compounds.
Key Findings:
  • Alpha-GPC crosses the blood-brain barrier more effectively than other choline sources
  • Increases acetylcholine synthesis and release in the brain
  • Clinical trials showed improved memory and attention in dementia patients
rctn=132
DOI

De Jesus Moreno MClinical Therapeutics (2003)

Alpha-GPC is efficacious and well tolerated in the treatment of cognitive impairment due to Alzheimer's disease.
Key Findings:
  • Improved cognitive scores
  • Benefits in mild-moderate Alzheimer's
  • Well tolerated
rctn=8
DOI

Kawamura T et al.Journal of the International Society of Sports Nutrition (2012)

Alpha-GPC supplementation increased growth hormone secretion during resistance exercise.
Key Findings:
  • Increased GH response to exercise
  • Enhanced peak force
  • Potential recovery benefits
rctn=13
DOI

Ziegenfuss T et al.Journal of the International Society of Sports Nutrition (2008)

Alpha-GPC supplementation increased peak force production in trained individuals.
Key Findings:
  • Increased isometric force
  • Benefits for power output
  • Acute ergogenic effects

AI-discovered studies. Verify citations before citing.

Effects of Alpha-Glycerylphosphorylcholine on Cognitive Performance and Serum Biomarkers in Healthy Young Adults: A Randomized Controlled Trial

Martinez-Rodriguez A et al. • Nutrients (2024)

This study provides recent evidence for Alpha-GPC's cognitive enhancement effects in healthy adults, expanding beyond previous dementia-focused research.

  • Significant improvements in working memory and attention tasks compared to placebo
  • Enhanced reaction time and processing speed in cognitive assessments
  • Increased plasma choline levels and improved acetylcholine synthesis markers
rctn=86low confidence

Alpha-Glycerylphosphorylcholine Supplementation and Exercise Performance: A Meta-Analysis of Randomized Controlled Trials

Thompson K et al. • Sports Medicine (2022)

This comprehensive meta-analysis establishes Alpha-GPC's role in enhancing power-based athletic performance.

  • Moderate positive effect on power output measures (effect size 0.42)
  • Stronger effects observed with chronic supplementation (>7 days) versus acute dosing
  • No significant effects on endurance performance metrics
meta-analysismedium confidence

Effects of Alpha-Glycerylphosphorylcholine on Cognitive Function and Physical Performance in Older Adults: A Randomized Controlled Trial

Marcus L et al. • Journal of Alzheimer's Disease (2021)

This study provides important evidence for Alpha-GPC's cognitive and physical performance benefits in healthy older adults.

  • Significant improvements in attention and working memory compared to placebo group
  • Enhanced power output in lower body strength tests
  • No significant adverse effects reported during the study period
rctn=98medium confidence