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L-Theanine vs Caffeine

Evidence-based comparison from our database of 3,862 ingredients

TL;DR

L-Theanine is typically chosen for relaxation, while Caffeine is used for alertness. Neither outranks the other. The right pick depends on the goal, and the two are not interchangeable.

L-Theanine

The zen switch.

Research depthWell studied
Effective Dose100-200mg
Time to EffectEffects within minutes to hours

Commonly used for:

relaxationcalm focus at a desksmoothing out caffeine jitters

Caffeine

The world's favorite stimulant.

Research depthExtensively studied
Effective Dose100-400mg
Time to EffectEffects within minutes to hours

Commonly used for:

alertnessfocustraining output

Side-by-Side Comparison

FactorL-TheanineCaffeine
Research depthWell studiedExtensively studied
Effective Dose100-200mg100-400mg
Time to EffectEffects within minutes to hoursEffects within minutes to hours
Commonly used forrelaxation, calm focus at a deskalertness, focus

Which fits which goal

These two do different jobs, so the comparison ends at the goal, not at a ranking. Match the ingredient to what you are trying to change and check the dose against the amount on the label.

Reach for L-Theanine when:

  • • The goal is relaxation
  • • The goal is calm focus at a desk

Reach for Caffeine when:

  • • The goal is alertness
  • • The goal is focus

Frequently Asked Questions

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This comparison is for informational purposes only and should not replace professional medical advice. Always consult a healthcare provider before starting any supplement regimen, especially if you have existing health conditions or take medications.