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Science8 min readApr 5, 2026
The 1:2 Ratio: The Caffeine + L-Theanine Stack Big Tech Doesn't Talk About
Why 100mg caffeine paired with 200mg L-Theanine produces measurable cognitive gains — and how to dose it correctly.
D
Dr. Eli Rhodes
Performance Neuroscience
Three peer-reviewed papers between 2008 and 2014 quietly settled an argument that the supplement industry had been having for two decades. Caffeine alone improves reaction time. L-Theanine alone improves attention. Together, in a 1:2 ratio, they produce a third effect that neither does alone — sustained, calm, alert focus measurable on EEG.
The key word is ratio. 100mg caffeine to 200mg L-Theanine. Not 50:50. Not 1:1. Two parts L-Theanine for every one part caffeine. Off by 30% and the effect collapses.
Energy + Focus is engineered to that ratio. Not because it sounds nice on the label — because the studies say it works.
About the author
D
Dr. Eli Rhodes
Performance Neuroscience
