Comparison
Magnesium Glycinate vs N-Acetyl Cysteine
Side-by-side of Magnesium Glycinate and N-Acetyl Cysteine. 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.
Magnesium Glycinate
Magnesium glycinate supplement guide: chelated bisglycinate form, 200 to 400 mg dosage, sleep architecture benefits, low GI side effects, glycine co-effect.
N-Acetyl Cysteine
NAC supplement benefits cover glutathione synthesis, liver and antioxidant support, and hangover recovery. Evidence strongest at 1200-2400 mg/day.
Effects at a glance
Magnesium Glycinate
- •Shortens sleep onset latency in older adults and in deficient populations supplementing 200 to 400 mg elemental Mg
- •Improves subjective sleep quality scores (PSQI, ISI) modestly versus placebo over 4 to 8 weeks
- •Reduces nocturnal leg cramps and exercise-induced muscle cramping in some controlled trials
- •Lowers self-reported anxiety in mild-to-moderate cases, with smaller effect than first-line pharmacotherapy
- •Glycinate form delivers fewer GI side effects than oxide or citrate at equivalent elemental doses
- •Insufficient as a stand-alone hypertension treatment; small adjunctive blood-pressure reductions only
N-Acetyl Cysteine
- •Replenishes intracellular glutathione by supplying cysteine, the rate-limiting amino acid for synthesis
- •First-line antidote for acetaminophen toxicity, restoring hepatic glutathione before fulminant injury occurs
- •Reduces sputum viscosity in chronic bronchitis and COPD at 600 to 1200 mg/day over months
- •Modest symptom reductions in OCD and trichotillomania at 1200 to 2400 mg/day across small RCTs
- •Mixed evidence for psychiatric adjunct use in bipolar depression and schizophrenia negative symptoms
- •Inhaled forms can trigger bronchospasm in active asthma; oral use is the standard biohacker route
Side-by-side
| Attribute | Magnesium Glycinate | N-Acetyl Cysteine |
|---|---|---|
| Category | supplement | supplement |
| Also known as | magnesium bisglycinate | NAC |
| Half-life (hr) ↗ | 5 | 5.6 |
| Typical dose (mg) ↗ | 300 | 1200 |
| Dosing frequency | daily (often evening) | 1 to 3 times daily, split dosing preferred |
| Routes | oral | oral, iv |
| Onset (hr) | 1 | 1 |
| Peak (hr) | - | 2 |
| Molecular weight | - | 163.19 |
| Molecular formula | - | C5H9NO3S |
| Mechanism | Magnesium acts as a cofactor for 300+ enzymes and as a voltage-dependent antagonist at NMDA receptors; glycine serves as an inhibitory neurotransmitter and co-agonist at glycine receptors. | Deacetylated to cysteine, the rate-limiting precursor for glutathione synthesis; also directly scavenges reactive oxygen species and modulates glutamate signaling. |
| Legal status | Dietary supplement | OTC in most jurisdictions; restricted periods in US history (FDA reclassified 2022) |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement | OTC supplement (US, post-2022); Rx indications also exist (acetaminophen overdose, mucolytic) |
| Pregnancy | Generally considered acceptable at RDA doses; consult clinician | Used clinically in pregnancy for specific indications; consult clinician |
| CAS | 14783-68-7 | 616-91-1 |
| PubChem CID | 84645 | 12035 |
| Wikidata | - | Q413299 |
Safety profile
Magnesium Glycinate
Common side effects
- mild GI upset at high doses
- loose stools (dose-dependent, less than with oxide/citrate forms)
Contraindications
- severe renal impairment
- myasthenia gravis
- heart block
Interactions
- tetracycline and fluoroquinolone antibiotics: magnesium chelates antibiotic, reducing absorption; separate by 2+ hours(moderate)
- bisphosphonates: reduced absorption of bisphosphonate(moderate)
- potassium-sparing diuretics: possible hypermagnesemia in renal impairment(moderate)
N-Acetyl Cysteine
Common side effects
- sulfur-like taste or odor
- nausea
- flatulence
- diarrhea
Contraindications
- active asthma attack (inhaled form can trigger bronchospasm)
- known NAC hypersensitivity
Interactions
- nitroglycerin: potentiates vasodilation, risk of hypotension and headache(moderate)
- activated charcoal: reduces NAC absorption when used for acetaminophen overdose(moderate)
- anticoagulants: theoretical additive antiplatelet effect at high doses(minor)
Which Should You Take?
Magnesium Glycinate 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. N-Acetyl Cysteine is the right call when one of the conditionals below applies.
- → If your priority is sleep onset or sleep quality, pick Magnesium Glycinate.
- → If your priority is stress and HPA-axis regulation, pick Magnesium Glycinate.
- → If your priority is healthspan extension, pick N-Acetyl Cysteine.
- → If your priority is liver function, pick N-Acetyl Cysteine.
Default choice: Magnesium Glycinate. Lower friction to source, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for N-Acetyl Cysteine 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 Magnesium Glycinate and N-Acetyl Cysteine?
Magnesium Glycinate and N-Acetyl Cysteine 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, Magnesium Glycinate or N-Acetyl Cysteine?
Magnesium Glycinate half-life is 5 hours; N-Acetyl Cysteine half-life is 5.6 hours.
Can you stack Magnesium Glycinate with N-Acetyl Cysteine?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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