NAC (N-Acetyl Cysteine) vs Quercetin
Immune vs Immune · evidence-backed comparison
- • NAC (N-Acetyl Cysteine) has the stronger evidence base (strong (multiple rcts / meta-analyses)).
- • NAC (N-Acetyl Cysteine) has the broader effect profile across the 9 effect categories.
- • NAC (N-Acetyl Cysteine) is cheaper per serving ($0.22 vs $0.35).
- • NAC (N-Acetyl Cysteine) has higher bioavailability (better absorption).
Side-by-side traits
| Trait | NAC (N-Acetyl Cysteine) | Quercetin |
|---|---|---|
Category | Immune | Immune |
Active compound | N-acetyl L-cysteine | Quercetin |
Form available | Capsule, Powder | Capsule, Tablet |
Source | synthetic | plant |
Typical dose | 600–1800 mg daily | 500–1000 mg daily |
Dose range | 600–1800 mg | 500–1000 mg |
Loading protocol | — | — |
Best taken with | empty stomach or with food | vitamin C (potentiates) |
Best time of day | any | any |
Bioavailability How efficiently the body absorbs and utilizes the compound. | Moderate (3/5) | Low (2/5) |
Onset time | Acute and cumulative | Cumulative: 2–6 weeks |
Half-life | ~6 hours | ~17 hours |
Evidence level Quality and quantity of human research. | Strong (multiple RCTs / meta-analyses) | Moderate (some RCTs) |
Overall effect Subjective effect magnitude. | Moderate (3/5) | Low (2/5) |
Muscle / strength | Low (2/5) | Very Low (1/5) |
Physical energy | Low (2/5) | Low (2/5) |
Focus / cognition | Low (2/5) | Very Low (1/5) |
Mood / stress | Moderate (3/5) | Very Low (1/5) |
Sleep quality | Very Low (1/5) | Very Low (1/5) |
Immunity | High (4/5) | High (4/5) |
Recovery Post-exercise recovery support. | Moderate (3/5) | Moderate (3/5) |
Longevity / healthspan | High (4/5) | 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. | $0.22 | $0.35 |
Vegan friendly | Yes | Yes |
Gluten free | Yes | Yes |
3rd-party tested | Yes | Yes |
About NAC (N-Acetyl Cysteine)
Glutathione precursor used clinically for liver protection (acetaminophen overdose). Strong evidence for OCD, COPD, and PCOS.
About Quercetin
Polyphenol with antihistamine and senolytic properties. Common in protocols for allergies and viral infections; pair with vitamin C.
Vetted brands, third-party testing, ships worldwide.
Vetted brands, third-party testing, ships worldwide.
NAC (N-Acetyl Cysteine) safety
Common side effects:
- • Sulfur smell
- • GI upset
- • Headache
Avoid if:
- • Asthma (rare bronchospasm)
Drug interactions:
- • Nitroglycerin
- • Anticoagulants
- • Activated charcoal
Quercetin safety
Common side effects:
- • Headache
- • Tingling extremities (high doses)
Avoid if:
- • Kidney disease
Drug interactions:
- • Cyclosporine
- • Quinolone antibiotics
- • Anticoagulants
Common uses
- • Liver protection
- • Lung health
- • OCD / mental health
- • PCOS
Stacks well with: Vitamin C, Selenium (Selenomethionine)
Common uses
- • Seasonal allergies
- • Immune support
- • Senescent cell clearance
Stacks well with: Vitamin C, Zinc
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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.