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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
8 of 9 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both Caffeine and EAAs have evidence — compare verdict strength side-by-side.
100-200mg
Morning, 30-60 minutes before exercise
Pill/capsule for precise dosing
10-15g EAAs (containing 3-4g leucine)
Intra-workout, Post-workout, Between meals
Free-form EAA powder (instantized for mixing)
15-45 minutes
30-60 minutes
30-60 minutes
30-60 minutes
Acute (within hours)
24-72 hours
During caloric deficit
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).
Peri-operative protein or amino acid supplementation for total joint arthroplasty: a systematic review and meta-analysis
Journal of orthopaedic surgery and research (2025) · Meta analysis · n=903
Essential amino acids (EAA) significantly reduced muscle atrophy in quadriceps femoris muscle mass (SMD: 0.69; 95% CI: 0.44 to 0.95) and hamstring muscle mass (SMD: 1.04; 95% CI: 0.52 to 1.55).
The Association of the Essential Amino Acids Lysine, Methionine, and Threonine with Clinical Outcomes in Patients at Nutritional Risk: Secondary Analysis of a Randomized Clinical Trial
Nutrients (2024) · Rct · n=237
In a model adjusted for comorbidities, sex, nutritional risk, and trial intervention, low plasma methionine levels were associated with 30-day mortality (adjusted HR 1.98 [95% CI 1.16 to 3.36], p = 0.01) and with a decline in functional status (adjusted OR 2.06 [95% CI 1.06 to 4.01], p = 0.03).
Exercise Programs Combined with Diet Supplementation Improve Body Composition and Physical Function in Older Adults with Sarcopenia: A Systematic Review
Nutrients (2023) · Systematic review · n=16
A total of 16 studies met the inclusion criteria and were included in this systematic review.
Based on multiple meta-analyses showing 3-6mg/kg optimal dosing. Performance benefits plateau around 200-300mg with increased jitteriness at higher doses.
Based on studies showing EAA supplementation increases MPS rates. Effect magnitude conservative given limited dose-response data. Requires adequate leucine content (3-4g). Individual response varies significantly.
AI-estimated from published studies. Interpret as directional guidance.
Caffeine has a higher evidence score (9.5/10 vs 7.5/10) and wins in 2 of 3 categories.
For boost daily energy, Caffeine has a higher relevance score (98 vs 48).
No known interactions between Caffeine and EAAs have been documented in our database. However, always consult a healthcare provider before combining supplements.