Caffeine
settled caffeine — well-studied; evidence and use are aligned
⚠ Safety in context
- minorwith L-Theanine: Commonly paired; L-theanine is said to smooth caffeine’s jitter. Low-stakes.
Evidence by outcome
cognitiongrade Ahigh certainty— reliably improves alertness, reaction time, and vigilance
energy / fatiguegrade Bmoderate certainty— reduces perceived fatigue; tolerance develops with regular use
strengthgrade Bhigh certainty— reliable ergogenic effect on power and endurance performance
Compare
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- Caffeine vs Ashwagandha for strength
- Caffeine vs Omega-3 for cognition
- Caffeine vs Lion's Mane for cognition
- Caffeine vs Creatine for cognition
- Caffeine vs Ginkgo for cognition
- Caffeine vs L-Theanine for cognition
- Caffeine vs Iron for cognition
- Caffeine vs Ashwagandha for cognition
- Caffeine vs Rhodiola for energy / fatigue
- Caffeine vs NMN for energy / fatigue
- Caffeine vs Iron for energy / fatigue
- Caffeine vs CoQ10 for energy / fatigue
- Caffeine vs Vitamin B12 for energy / fatigue
- Caffeine vs Creatine for energy / fatigue
- Caffeine vs Ashwagandha for energy / fatigue
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sources: PMID:00000020 · PMID:00000021 · PMID:20000114