Melatonin vs NAC (N-Acetyl Cysteine)
Sleep vs Immune · evidence-backed comparison
- • NAC (N-Acetyl Cysteine) has the broader effect profile across the 9 effect categories.
- • Melatonin is cheaper per serving ($0.05 vs $0.22).
Side-by-side traits
| Trait | Melatonin | NAC (N-Acetyl Cysteine) |
|---|---|---|
Category | Sleep | Immune |
Active compound | N-acetyl-5-methoxytryptamine | N-acetyl L-cysteine |
Form available | Capsule, Tablet, Liquid, Gummy | Capsule, Powder |
Source | synthetic | synthetic |
Typical dose | 0.3–3 mg | 600–1800 mg daily |
Dose range | 0.3–3 mg | 600–1800 mg |
Loading protocol | — | — |
Best taken with | 30–60 min before bed | empty stomach or with food |
Best time of day | evening | any |
Bioavailability How efficiently the body absorbs and utilizes the compound. | Moderate (3/5) | Moderate (3/5) |
Onset time | Acute: 30–60 min | Acute and cumulative |
Half-life | 20–50 min | ~6 hours |
Evidence level Quality and quantity of human research. | Strong (multiple RCTs / meta-analyses) | Strong (multiple RCTs / meta-analyses) |
Overall effect Subjective effect magnitude. | Moderate (3/5) | Moderate (3/5) |
Muscle / strength | Very Low (1/5) | Low (2/5) |
Physical energy | Very Low (1/5) | Low (2/5) |
Focus / cognition | Very Low (1/5) | Low (2/5) |
Mood / stress | Low (2/5) | Moderate (3/5) |
Sleep quality | Very High (5/5) | Very Low (1/5) |
Immunity | Low (2/5) | High (4/5) |
Recovery Post-exercise recovery support. | Moderate (3/5) | Moderate (3/5) |
Longevity / healthspan | Moderate (3/5) | High (4/5) |
Safety rating 5 = exceptionally well-tolerated; 1 = significant risk profile. | High (4/5) | High (4/5) |
Price per serving Approximate USD per typical daily dose. | $0.05 | $0.22 |
Vegan friendly | Yes | Yes |
Gluten free | Yes | Yes |
3rd-party tested | Yes | Yes |
About Melatonin
Pineal-gland hormone that signals 'night-time' to the body. Most useful for jet lag and shifted sleep schedules; lower doses (0.3 mg) often work better than 5–10 mg.
About NAC (N-Acetyl Cysteine)
Glutathione precursor used clinically for liver protection (acetaminophen overdose). Strong evidence for OCD, COPD, and PCOS.
Vetted brands, third-party testing, ships worldwide.
Vetted brands, third-party testing, ships worldwide.
Melatonin safety
Common side effects:
- • Vivid dreams
- • Morning grogginess (high doses)
- • Headache
Avoid if:
- • Autoimmune disease
- • Pregnancy
- • Driving for hours after
Drug interactions:
- • Birth control
- • Anticoagulants
- • Antidepressants
- • Diabetes meds
NAC (N-Acetyl Cysteine) safety
Common side effects:
- • Sulfur smell
- • GI upset
- • Headache
Avoid if:
- • Asthma (rare bronchospasm)
Drug interactions:
- • Nitroglycerin
- • Anticoagulants
- • Activated charcoal
Common uses
- • Jet lag
- • Shift work
- • Sleep onset
- • Circadian rhythm
Stacks well with: Magnesium Glycinate, Glycine
Common uses
- • Liver protection
- • Lung health
- • OCD / mental health
- • PCOS
Stacks well with: Vitamin C, Selenium (Selenomethionine)
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Medical disclaimer
SupplementDuel is for educational purposes only and is not medical advice. Consult a physician before starting, stopping, or combining supplements — especially if you are pregnant, breastfeeding, take prescription medication, or have a chronic condition.