Related Compounds
Compounds connected by the same goals, effects, or research topics.
Compound Profile
Caffeine L-Theanine
May support acute attention and mood outcomes in healthy participants.
Use extra caution — Safety evidence: the combination's risk is strongly influenced by caffeine dose and individual sensitivity. Details
Last reviewed: •2 sources citedReport a correctionProfile-wide ·B Moderate
At a glance
From this profile's structured data- Evidence
- Grade B
- Safety
- Safety evidence: the combination's risk is strongly influenced by caffeine dose and individual sensitivity.
- Profile context
- adenosine glutamate
Quick stats
- Evidence level
- Moderate evidence
- Typical onset
- Varies by prep
- Safety rating
- Use extra caution: Use caution
- Best for
- Adenosine Glutamate
Safety
Safety & Cautions
Elevated caution
Caution level: Elevated. One caution category applies — read it before use.
- Stimulant-Like ProfileStimulant-like or activating caution language is present.
- Safety evidence
- the combination's risk is strongly influenced by caffeine dose and individual sensitivity
- Who should avoid this?
- No specific evidence-backed contraindication is documented for this profile. This is not the same as established safety.
- Talk to a professional if
- you are pregnant or breastfeeding.
Sleep disruption, anxiety-like symptoms, cardiovascular effects, pregnancy intake limits, total caffeine exposure, and concurrent stimulants require attention; long-term combination-specific evidence remains limited.
Evidence Summary
Profile-wide ·B ModerateEvidence lens
Useful signal, but study design, dose, and population still matter.
ModerateModerate evidence
Human clinical evidence: Present in source signals
Mechanistic / preclinical: Mechanism mapped — Neurotransmitter Modulation · Vascular Function Support · Stress Response Modulation
Research maturity: Established research — main contexts: Adenosine Glutamate
Safety boundary: Safety note available — Safety evidence: the combination's risk is strongly influenced by caffeine dose and individual sensitivity.
This profile cites 2 human studies.
Evidence Strength
Confidence estimate based on the design quality and consistency of published clinical trials.
Caffeine L-Theanine has a moderate evidence rating.
AdaptogenFocusStress & Mood
Citation density
2.0
Sources
2
Effects
1
Research recency
Mixed recency
Evidence Grade
Grade B: Moderate Evidence
Evaluation of methodological rigor, population reach, and evidence alignment.
- Design Match
- Meta analysis
- Risk of Bias
- Low
- Consistency
- Consistent
Strongest recorded design is a meta analysis, drawn from 3 recorded studies, 3 in people. No disagreement is recorded across them.
How evidence grades work
Each grade reflects the strength and consistency of published human evidence — not marketing claims. Grades are based on study count, design quality, effect size, consistency, and recency.
- Strong
- Multiple RCTs, consistent direction, adequate effect size
- Moderate
- Some RCTs or consistent observational data in humans
- Preliminary / Mixed
- Animal or in-vitro only, or conflicting human data
- Traditional / Theoretical
- Traditional use only; no controlled human trials
Clinical Study Summaries (2)1 human evidence source · 1 human trial · ~27 participants across 1 human evidence source with reported N · Consistency not yet classifiable
Filter by study class
Showing 2 of 2 studies.
What the evidence actually shows
This table contains 2 structured sources, including 1 human evidence source; 1 is a human trial. Across 1 human evidence source with a reported sample size, the approximate participant total is 27; overlapping publications may include some of the same people.
| Study | Design | N | Dose | Duration | Population | Outcome | Result & magnitude | Source |
|---|---|---|---|---|---|---|---|---|
The combined effects of L-theanine and caffeine on cognitive performance and mood PubMed · Nutr Neurosci · 2008 Background | Randomized controlled trial Randomly assigns participants to interventions or controls, reducing many sources of bias when the trial is conducted well. | n=27 | — | — | — | — | — | PubMed → |
Payne et al. · Nutrition Reviews · 2025 Background | Other / unclear The study design is not yet classified clearly enough to infer its place in the evidence hierarchy. | — | — | — | — | — | — | Source → |
How Caffeine L-Theanine Works
Simplified mechanism pathway based on preclinical and pharmacological evidence. Does not confirm clinical efficacy.
Mechanism Pathway — How Caffeine L-Theanine Works
CompoundTarget / ReceptorMechanismEffect / Outcome
Dosing
- No standardized dose
- Theanine plus caffeine; tea/bioactive supplement context. Add timing/caffeine dose cautions; separate from standalone L theanine.
Mechanisms & biological pathways
Preclinical mechanism details from scientific profiles; these represent plausible pathways but do not guarantee clinical efficacy in humans.
- Neurotransmitter Modulation
- Vascular Function Support
- Stress Response Modulation
- Neuroprotective Activity
Guides that use Caffeine L-Theanine
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Compare & Sourcing
Compare side-by-side tradeoffs or verify active marker guidelines.
Review available sources for Caffeine L-Theanine
Independent database mapping — evaluated separately from safety and efficacy scores.
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Safety first · Harm reduction
This information is educational and not medical advice. Start low, avoid risky combinations, and consult a licensed clinician before making health decisions—especially if you use medications, have diagnosed conditions, or are pregnant/breastfeeding.
Learn how we evaluate confidence, safety, and intensity on the methodology page.
Editorial Review
Checked against primary sources, cited evidence, and contraindication language before publication. Evidence claims, safety language, and affiliate modules are reviewed independently. Not personal medical advice.
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