Caffeine and L-Theanine: Interaction Overview
L-theanine (gamma-glutamylethylamide) promotes alpha-wave activity via GABA-A receptor modulation and dampens the anxiogenic effects of caffeine's adenosine antagonism.
Mechanism of Interaction
L-theanine (gamma-glutamylethylamide) promotes alpha-wave activity via GABA-A receptor modulation and dampens the anxiogenic effects of caffeine's adenosine antagonism. Together, they produce clean alertness without jitteriness. Multiple RCTs confirm improved attention, reaction time, and reduced side effects vs. caffeine alone. The 2:1 ratio (e.g. 200mg L-theanine + 100mg caffeine) is most studied.
Recommendation
Stack freely. Start with 100mg caffeine + 200mg L-theanine. Adjust ratio to preference — some users prefer 1:1, some 3:1 (theanine:caffeine).
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L-Theanine
Learn about L-Theanine's dosage, half-life, and other interactions.
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