Alpha-GPC
Summary
Alpha-GPC is a choline source. Trials in Alzheimer-type dementia and mild cognitive impairment found better cognitive scores than placebo (grade B), and small studies in healthy men reported short-term gains in force and attention (grade D). A Korean cohort of 12 million adults linked prescribed alpha-GPC to higher 10-year stroke risk.
Key facts
How it works
ProposedAlpha-GPC supplies choline, which the body uses to make acetylcholine and phospholipids. Gut bacteria can turn choline into TMAO, a metabolite studied as a possible cardiovascular risk factor; mouse work links alpha-GPC to atherosclerosis through this route.[1][8]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Cognition | Grade B | Improved | RCT · n = 261 · 2003 | 3 rows |
| Exercise | Grade D | Improved | Crossover RCT · n = 13 · 2015 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Cognitive scores in mild to moderate Alzheimer-type dementia | Improved | Grade B | RCT · n = 261 · 2003 Adults aged 60–80 with mild to moderate Alzheimer-type dementia Form: Choline alfoscerate capsules · Dose: 400 mg three times daily (1,200 mg/day) · Duration: 180 days ADAS-Cog, MMSE and global impression scores improved versus placebo at 90 and 180 days. | 12637119 (opens PubMed)Source [2] |
| Cognitive scores in mild cognitive impairment | Improved | Grade B | RCT · n = 100 · 2024 Adults with mild cognitive impairment Form: Alpha-GPC soft capsule · Dose: 600 mg/day · Duration: 12 weeks ADAS-Cog improved by 2.34 points more than placebo; adverse events did not differ between groups. | 39300341 (opens PubMed)Source [3] |
| Attention test (Stroop) after one dose | Improved | Grade D | Crossover RCT · n = 20 · 2024 Resistance-trained men Form: Alpha-GPC (GeniusPure) · Dose: 315 mg or 630 mg single dose · Duration: Single dose Stroop scores improved more after both doses than after placebo 60 minutes after intake. | 39683633 (opens PubMed)Source [6] |
| Lower-body force production | Improved | Grade D | Crossover RCT · n = 13 · 2015 College-aged men Form: Alpha-GPC · Dose: 600 mg/day · Duration: 6 days Isometric mid-thigh pull peak force rose more than with placebo; upper-body force did not differ. | 26582972 (opens PubMed)Source [5] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Alpha-GPC (choline alfoscerate) | Varies[10] | Plasma choline exposure was similar to other choline supplements in a small crossover study, and TMAO rose quickly (n=6).[9] | Adverse events did not differ from placebo in the 12-week MCI trial.[3] | Cognition trials in dementia and MCI; short exercise studies |
Studied doses
Doses studied in human trials ranged from single doses of 315–630 mg in healthy men to 600 mg/day for 12 weeks in mild cognitive impairment and 1,200 mg/day (400 mg three times daily) for 180 days in Alzheimer-type dementia.[6][3][2]
Intake reference: Alpha-GPC has no intake reference of its own. For total choline, adults have an Adequate Intake of 425 mg/day (women) and 550 mg/day (men) and a UL of 3,500 mg/day.[1] NIH ODS fact sheet (updated June 2, 2022).
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
Other supplements
- Other choline sourcesNIH fact sheetCholine from all sources counts toward the 3,500 mg/day upper limit, set because high intakes cause fishy body odour, sweating and low blood pressure.[1]
Who should be careful
- Stroke risk factors
- In a South Korean national cohort, prescribed alpha-GPC was associated with higher 10-year stroke risk in a dose-response pattern; this is observational and does not prove cause.[7]
- Pregnancy and breastfeeding
- Trials cited here did not enrol pregnant or breastfeeding people; choline needs in pregnancy are covered on the choline page.[1]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Frequently asked questions
Does alpha-GPC improve memory in healthy people?
Evidence in healthy adults is limited to small, short studies. The stronger trials enrolled people with dementia or mild cognitive impairment.[6][2]
How much choline is in alpha-GPC?
About 40% of alpha-GPC by weight is choline, so 600 mg supplies roughly 240 mg of choline.[10]
Is alpha-GPC linked to stroke?
A 2021 cohort of 12 million Korean adults found higher stroke risk among people prescribed alpha-GPC. It was observational, so it shows an association, not proof.[7]
Alpha-GPC or citicoline?
Both supply choline. No head-to-head trial in healthy adults is cited here; each has its own trials in different groups.[3]
Sources
- [1]Choline: Fact Sheet for Health Professionals. NIH Office of Dietary Supplements, 2022. fact-sheet
- [2]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.. Clin Ther, 2003. RCT
- [3]Efficacy and safety of choline alphoscerate for amnestic mild cognitive impairment: a randomized double-blind placebo-controlled trial.. BMC Geriatr, 2024. RCT
- [4]Activity of Choline Alphoscerate on Adult-Onset Cognitive Dysfunctions: A Systematic Review and Meta-Analysis.. J Alzheimers Dis, 2023. meta-analysis
- [5]The effect of 6 days of alpha glycerylphosphorylcholine on isometric strength.. J Int Soc Sports Nutr, 2015. crossover-RCT
- [6]Acute Alpha-Glycerylphosphorylcholine Supplementation Enhances Cognitive Performance in Healthy Men.. Nutrients, 2024. crossover-RCT
- [7]Association of L-α Glycerylphosphorylcholine With Subsequent Stroke Risk After 10 Years.. JAMA Netw Open, 2021. observational
- [8]The Nutritional Supplement L-Alpha Glycerylphosphorylcholine Promotes Atherosclerosis.. Int J Mol Sci, 2021. animal-study
- [9]Differential metabolism of choline supplements in adult volunteers.. Eur J Nutr, 2022. PK-study
- [10]Glycerophosphocholine (compound summary). PubChem, NIH National Library of Medicine, 2026. database
What changed
- First draft. Every PMID checked against NCBI E-utilities (title, journal and year taken from the PubMed record) and each evidence row written from its PubMed abstract.