BulkSupplements · Alpha-GPC · Capsules
Is BulkSupplements Alpha GPC 300 mg Capsules underdosed?
1 serving = 2 capsulesDirections: 1 serving a dayLabel as of 24 Apr 2025 · NIH DSLD
Verdict
300 mg a dayas the label directs · studies use 250–600 mg/day of alpha-gpc
Effective doseTaken as the label directs (1 serving a day, 300 mg each), it gives 300 mg a day; studies use 250–600 mg/day.
One capsule gives 150 mg, so reaching the low end of what studies use (250 mg) takes 1.7 capsules a day; it ranks 5th of 9 alpha-GPC supplements here by dose.
2 capsules a day reach 250 mg.
What the label says
- Alpha-GPC per serving
- 300 mg in 2 capsules
- Servings a day
- 1 serving a day
- Alpha-GPC a day, as directed
- 300 mg
- Research dose
- 250–600 mg/day Evidence: Weak
Suggested use: As a dietary supplement, take 2 capsules once daily, or as directed by a physician.
Also on the label
| Ingredient | Per serving | Verdict |
|---|---|---|
| Calcium | 60 mg | Not graded |
| Phosphorus | 47 mg | Not graded |
More about alpha-gpc: forms, timing and the studies behind the dose.
Same category, compared
All 9 alpha-GPC supplements we checked, ranked by dose (commission never changes the order). Studies use 250–600 mg/day of alpha-gpc; servings counted to 250 mg.
| Product | Per serving | Servings to reach it | Form |
|---|---|---|---|
| Double Wood Alpha-GPC 300 mg | 600 mg | 1 or less | Capsules |
| NOW Alpha GPC 300 mg | 600 mg | 1 or less | Capsules |
| Nutricost Alpha GPC 600 mg | 600 mg | 1 or less | Capsules |
| Pure Encapsulations Alpha-GPC | 400 mg | 1 or less | Capsules |
| BulkSupplements Alpha GPC 300 mg Capsules (this product) | 300 mg | 1 or less | Capsules |
| Jarrow Formulas Alpha GPC 300 mg | 300 mg | 1 or less | Capsules |
| NutraBio Alpha GPC | 300 mg | 1 or less | Capsules |
| Swanson Alpha-GPC 300 mg | 300 mg | 1 or less | Capsules |
| Nootropics Depot Alpha GPC 150 mg Capsules | 150 mg | 1.7 | Capsules |
Where the reference doses come from
- Alpha-GPC, 250–600 mg/day: Bellar et al., 2015; Marcus et al., 2017.
- Label data: National Institutes of Health, Office of Dietary Supplements. Dietary Supplement Label Database, 2026. https://dsld.od.nih.gov/. Label 329912, including its servings a day.
For a supplement taken every day we judge the most the label's directions give in a day, and show the least. Read the full methodology or the corrections log.