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
Head-to-head evidence comparison — which supplement is right for you?
Caffeine wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
22 of 25 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
3 of 4 studies with measurable effects showed benefit.
Top outcomes
100-200mg
Morning, 30-60 minutes before exercise
Pill/capsule for precise dosing
2-6g daily
Before exercise for fatigue reduction, Before bed for sleep support
L-Ornithine HCl
15-45 minutes
30-60 minutes
30-60 minutes
30-60 minutes
During prolonged exercise
Hours post-exercise
1-2 weeks
Immediate
Effect of Acute Caffeine Intake on the Fat Oxidation Rate during Exercise: A Systematic Review and Meta-Analysis
Nutrients (2020) · Meta analysis · n=2020
A subsequent meta-analysis was performed using the random effects model to calculate the standardized mean difference (SMD).
The effects of caffeine intake on weight loss: a systematic review and dos-response meta-analysis of randomized controlled trials
Critical reviews in food science and nutrition (2019) · Meta analysis · n=606
Thirteen RCTs with 606 participants were included in the meta-analyses.
Effect of Caffeine and Nitrates Combination on Exercise Performance, Heart Rate and Oxygen Uptake: A Systematic Review and Meta-Analysis
Nutrients (2024) · Meta analysis · n=95
The meta-analysis revealed that caffeine and nitrates supplementation (CAF+nitrates) did not enhance performance in time trials (TTs) over the CAF alone (g = -0.06; 95% CI = -0.46 to 0.35; p = 0.78) or nitrates alone (g = 0.29; 95% CI = -0.12 to 0.70; p = 0.17).
Comparative Efficacy of Treatment Options for Minimal Hepatic Encephalopathy: A Systematic Review and Network Meta-Analysis
Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association (2020) · Meta analysis · n=1563
In a meta-analysis of data from 25 trials, we found rifaximin and lactulose to be most effective for reversal of minimal HE in patients with cirrhosis.
Safety assessment of L-ornithine oral intake in healthy subjects: a systematic review
Amino acids (2025) · Systematic review
The main observed adverse events were gastrointestinal disorders.
Efficacy of L-ornithine L-aspartate for minimal hepatic encephalopathy in patients with cirrhosis: A meta-analysis of randomized controlled trials
Arab journal of gastroenterology : the official publication of the Pan-Arab Association of Gastroenterology (2024) · Meta analysis · n=292
LOLA has significant beneficial effects on reversal of MHE and prevention of OHE in patients with cirrhosis compared with placebo or no intervention.
Based on multiple meta-analyses showing 3-6mg/kg optimal dosing. Performance benefits plateau around 200-300mg with increased jitteriness at higher doses.
Evidence specific to L-ornithine L-aspartate form in cirrhosis patients. Meta-analysis of 292 patients showed significant benefit vs placebo. GI adverse events noted as main side effect. Limited applicability to healthy populations.
AI-estimated from published studies. Interpret as directional guidance.
Caffeine has a higher evidence score (9.5/10 vs 8.5/10) and wins in 2 of 3 categories.
For improve endurance, Caffeine has a higher relevance score (85 vs 65).
No known interactions between Caffeine and Ornithine have been documented in our database. However, always consult a healthcare provider before combining supplements.