Comparison
Alpha-GPC vs Nicotinamide Riboside
Side-by-side of Alpha-GPC and Nicotinamide Riboside. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Alpha-GPC
Alpha GPC supplement profile: 300 to 600 mg dosage, acetylcholine synthesis, attention and reaction-time evidence, side effects, and choline donor comparisons.
Nicotinamide Riboside
Nicotinamide riboside (NR) is the most-studied NAD+ precursor in humans. Sold as Niagen by Chromadex; raises plasma NAD+ 30-60% at 250-1,000 mg/day.
Effects at a glance
Alpha-GPC
- •Choline donor supplement, roughly 40% choline by weight; crosses blood-brain barrier efficiently
- •Replicated small gains in attention and reaction time at 300 to 600 mg in healthy adults
- •Standard prescription cognitive medication in much of Europe (Gliatilin) at 1,200 mg/day for vascular cognitive impairment
- •ASCOMALVA trial (n=210) showed cognitive preservation when added to donepezil over 24 months
- •Increases acute power output (~14%, single trial) and transient growth hormone secretion at 600 mg
- •TMAO production raises a contested cardiovascular concern at chronic high doses
Nicotinamide Riboside
- •Most-studied NAD+ precursor in human trials; the original Niagen formulation by Chromadex
- •Plasma NAD+ rises 30-60% at 250-1,000 mg/day across multiple human PK trials
- •Martens 2018 reported reduced BP and arterial stiffness at 500 mg/day for 6 weeks
- •Dollerup 2018 found no insulin sensitivity change despite plasma NAD+ rise
- •Tissue NAD+ rise inconsistent; hard clinical endpoints not yet measured
- •Larger human safety database than NMN; comparable mechanistic effects
Side-by-side
| Attribute | Alpha-GPC | Nicotinamide Riboside |
|---|---|---|
| Category | supplement | supplement |
| Also known as | L-Alpha glycerylphosphorylcholine, choline alfoscerate, GPC, alpha-glyceryl phosphorylcholine | NR, Niagen, nicotinamide riboside chloride |
| Half-life (hr) ↗ | 4 | 8 |
| Typical dose (mg) ↗ | 600 | 500 |
| Dosing frequency | 1 to 3 times daily | daily, typically morning |
| Routes | oral | oral |
| Onset (hr) | 1 | 1 |
| Peak (hr) | 2 | 4 |
| Molecular weight | 257.22 | 255.25 |
| Molecular formula | C8H20NO6P | C11H15N2O5 |
| Mechanism | Hydrolyzed to free choline and glycerophosphate after absorption; choline supports acetylcholine and phosphatidylcholine synthesis in CNS. | NAD+ precursor via salvage pathway. Phosphorylated to NMN by nicotinamide riboside kinase (NRK), then converted to NAD+. Substrate for sirtuins, PARPs, and CD38. |
| Legal status | Dietary supplement (US); prescription medication in much of Europe | OTC dietary supplement |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement | OTC supplement |
| Pregnancy | Insufficient data; choline generally recommended in pregnancy | Insufficient data at supplement doses |
| CAS | 28319-77-9 | 1341-23-7 |
| PubChem CID | 71920 | 439924 |
| Wikidata | Q411478 | Q3343054 |
Safety profile
Alpha-GPC
Common side effects
- mild GI upset
- headache
- dizziness
- occasional insomnia with evening dosing
Contraindications
- established cardiovascular disease (TMAO concern)
- concurrent strong anticholinergic therapy
Interactions
- anticholinergic medications: partial mutual antagonism(minor)
- cholinesterase inhibitors (donepezil): additive cholinergic effect, basis for ASCOMALVA protocol(minor)
- scopolamine: partial counteraction of anticholinergic effect(minor)
Nicotinamide Riboside
Common side effects
- mild GI upset (rare)
- headache (rare)
Contraindications
- pregnancy / lactation (insufficient data)
- active cancer (theoretical, no contraindicating data)
Interactions
- pterostilbene: complementary sirtuin pathway (Basis combination)(minor)
- TMG (trimethylglycine): methylation support during high NAD+ precursor dosing(minor)
Which Should You Take?
Nicotinamide Riboside comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-A outcome catalogued. Alpha-GPC is the right call when one of the conditionals below applies.
- → If your priority is focus or working memory, pick Alpha-GPC.
- → If your priority is athletic performance, pick Alpha-GPC.
- → If your priority is healthspan extension, pick Nicotinamide Riboside.
- → If your priority is energy and stamina, pick Nicotinamide Riboside.
Default choice: Nicotinamide Riboside. Lower friction to source, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Alpha-GPC only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Alpha-GPC and Nicotinamide Riboside?
Alpha-GPC and Nicotinamide Riboside differ in category (supplement vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Alpha-GPC or Nicotinamide Riboside?
Alpha-GPC half-life is 4 hours; Nicotinamide Riboside half-life is 8 hours.
Can you stack Alpha-GPC with Nicotinamide Riboside?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper