Loading…
We use essential cookies (authentication, your saved goals/stack) by default. With your permission we'll also enable privacy-respecting analytics (Vercel Web Analytics, anonymous load-time metrics) and error-replay diagnostics (Sentry — DOM snapshots only when an error fires) so we can fix bugs faster. Learn more about cookies
Head-to-head evidence comparison — which supplement is right for you?
CoQ10 wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
17 of 21 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
9 of 11 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both CoQ10 and NAC have evidence — compare verdict strength side-by-side.
100-300mg daily
With fatty meal
Ubiquinol (reduced form)
600-1800mg daily
Away from food, Split into 2-3 doses
NAC capsules or powder
4-12 weeks
8-12 weeks
4-8 weeks
2-8 weeks
4-8 weeks
2-4 weeks
1-2 weeks
Immediate
Efficacy and Safety of Coenzyme Q10 Supplementation in the Treatment of Polycystic Ovary Syndrome: a Systematic Review and Meta-analysis
Reproductive sciences (Thousand Oaks, Calif.) (2023) · Meta analysis · n=1021
Only one RCT reported adverse events, and they found that patients had no adverse effects or symptoms following supplementation.
Coenzyme Q10 for heart failure
The Cochrane database of systematic reviews (2021) · Meta analysis · n=1573
Coenzyme Q10 probably reduces the risk of all-cause mortality more than control (RR 0.58, 95% CI 0.35 to 0.95; 1 study, 420 participants; number needed to treat for an additional beneficial outcome (NNTB) 13.3; moderate-quality evidence).
Antioxidants for female subfertility
The Cochrane database of systematic reviews (2017) · Meta analysis · n=6510
This suggests that among subfertile women with an expected clinical pregnancy rate of 22%, the rate among women using antioxidants would be between 27% and 33%.
Efficacy of N-Acetylcysteine in Polycystic Ovary Syndrome: Systematic Review and Meta-Analysis
Nutrients (2025) · Meta analysis · n=2515
NAC was associated with a statistically significant increase in progesterone (SMD 0.95, 95% CI: 0.13-1.77, p = 0.02) and endometrial thickness (SMD 0.58, 95% CI: 0.10-1.06, p = 0.02) compared to the placebo and other drugs (SMD 0.71, 95% CI: 0.48-0.94, p < 0.0001).
Efficacy of N-acetylcysteine for patients with depression: An updated systematic review and meta-analysis
General hospital psychiatry (2024) · Meta analysis · n=904
Our findings indicate that adjunctive NAC can ameliorate depressive symptoms in patients with psychiatric problems, particularly bipolar disorder.
N-acetylcysteine as a treatment for substance use cravings: A meta-analysis
Addiction biology (2024) · Meta analysis · n=623
The most targeted substance in the clinical trials was alcohol (3/9; 33.3%), followed by tobacco (2/9; 22.2%) and multiple substances (2/9; 22.2%).
Based on heart failure meta-analysis (n=1573) showing mortality reduction. Effectiveness conservative due to single primary study (n=420). Take with food to reduce GI upset. Ubiquinol forms may have better absorption.
Meta-analysis showed efficacy particularly in bipolar disorder patients. Effect appears as adjunctive treatment. Individual response varies significantly.
AI-estimated from published studies. Interpret as directional guidance.
CoQ10 has a higher evidence score (8/10 vs 6/10) and wins in 2 of 3 categories.
For fertility support, CoQ10 has a higher relevance score (90 vs 82).
No known interactions between CoQ10 and NAC have been documented in our database. However, always consult a healthcare provider before combining supplements.