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L-Theanine

Blood pressure and vascular health

Some findings are held for review

Some papers have not cleared source or result review, so their findings are not summarized yet.

No confirmed result is available to summarize with study conditions.

Publications for this result: 1 (1 awaiting review included)

Other outcomes and study details

Distinct publications linked to this topic: 1

  • Those papers are not summarized until review is complete.

This result is held for interpretation. That does not mean research found no effect.

Outcome groups needing additional review (1)
  • blood-pressure increases · Distinct papers needing additional review: 1Evidence criteria check: 1

One paper can appear under multiple measured outcomes or review reasons, so these counts should not be added together.

Research topics to explore

Research topics to explore

Review findings reported in each research area.

Topics with more linked papers appear first.

  • Stress and mood

    Related papers 17 · human comparison papers 2

    View results
    • HDRS · Improvement reported · Some studies included patients or people with a deficiency
    • markers of stress · No clear difference between groups

    More outcome groups: 10

  • Sleep

    Related papers 15 · human comparison papers 3

    View results
    • Insomnia symptoms · No clear difference between groups
    • Sleep quality · No clear difference between groups · Some studies used more than one ingredient · Some studies included patients or people with a deficiency

    More outcome groups: 13

  • Cognition

    Related papers 7 · comparison findings need further review

    View results
    • Attention · Interpretation held
    • attention on a switch task · Interpretation held

    More outcome groups: 6

  • Glucose and metabolic health

    Related papers 2 · comparison findings need further review

    View results
    • Body weight · Interpretation held
    • muscle glycogen · Interpretation held
  • Blood lipids

    Related papers 1 · comparison findings need further review

    View results
    • serum levels of cholesterol · Interpretation held
    • triglycerides · Interpretation held
  • Blood pressure and vascular health

    Related papers 1 · comparison findings need further review

    View selected result
  • Digestion and gut health

    Related papers 1 · comparison findings need further review

    View results
    • intestinal inflammation · Interpretation held
  • Exercise performance

    Related papers 1 · comparison findings need further review

    View results
  • Fatigue and energy

    Related papers 1 · comparison findings need further review

    View results
    • self-reported tiredness · Interpretation held
  • Immune and respiratory health

    Related papers 1 · comparison findings need further review

    View results
    • splenic organ index · Interpretation held
  • Nutrient status

    Related papers 1 · comparison findings need further review

    View results
Data coverage and detailed study classifications

Paper counts are separated by research topic below. One paper may contribute to multiple findings.

Analysis status: Public-ready

Ingredient analysis date:

How the grade was determined: C

The 9.4 evidence score includes 3 independent human studies and 3 clinical studies in the representative benefit area. The C tier remains conservative because of limited repetition across independent human clinical studies.

The grade is based mainly on the research area with the most evidence. It does not mean the same result was found in other areas.

Papers linked to this ingredient overall: 97

Papers linked to this topic 1 · distinct papers 1 · comparison findings need further review · papers needing additional review 1

Ingredient-wide papers, topic-linked papers, and sources in outcome groups use different scopes. Adding source counts may count the same paper more than once.

  • blood-pressure increases: Sources represented in this measurement group: 1 · Distinct papers with human comparisons for this outcome: 0

Stress and mood

What the research found

markers of stress

No clear difference in this measurement was found between the compared groups.

Controlled study in people · Separable contribution · General population

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

HDRS

The study reported improvement in this measurement.

Controlled study in people · Separable contribution · Patient group

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

HAMD-21 score

A change was reported before and after use. Its cause cannot be isolated.

Other evidence · Separable contribution · Patient group

Within-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

anti-stress effects

The study needs further checking before its result can be interpreted.

Review · Ingredient combination · Unspecified population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

anxiolytic and calming effect

The study needs further checking before its result can be interpreted.

Review · Unknown intervention · General population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

DASS-42 stress score

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

depression

The study needs further checking before its result can be interpreted.

Review · Unknown intervention · Unspecified population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

depressive-like behaviors

The study needs further checking before its result can be interpreted.

Animal study · indirect · Single ingredient · Patient group

This finding comes from animal or cell research. It does not establish the same effect in people.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

overall mood

The study needs further checking before its result can be interpreted.

Meta-analysis · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

state anxiety

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

subjective stress response to a multitasking cognitive stressor

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Tension-Anxiety scores

The study needs further checking before its result can be interpreted.

Controlled study in people · Single ingredient · General population

Within-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Unspecified measured outcome

The study needs further checking before its result can be interpreted.

Review · Single ingredient · Unspecified population

The comparison could not be confirmed.

Analysis coverage and paper counts

2 papers · 2 measured outcomes

2 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Unspecified measured outcome

The study needs further checking before its result can be interpreted.

Review · Single ingredient · Unspecified population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Unspecified measured outcome

The study needs further checking before its result can be interpreted.

Other evidence · Unknown intervention · Unspecified population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Unspecified measured outcome

The study needs further checking before its result can be interpreted.

Other evidence · Unknown intervention · Unspecified population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Unspecified measured outcome

The study needs further checking before its result can be interpreted.

Review · Unknown intervention · Unspecified population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Sleep

What the research found

Insomnia Severity Index

No clear difference in this measurement was found between the compared groups.

Controlled study in people · Single ingredient · Unspecified population

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Mean PSQI

No clear difference in this measurement was found between the compared groups.

Controlled study in people · Ingredient combination · Patient group

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

sleep efficiency

The study reported improvement in this measurement.

Controlled study in people · Single ingredient · Patient group

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

total PSQI score

A change was reported before and after use. Its cause cannot be isolated.

Other evidence · Ingredient combination · Patient group

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Within-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

sleep-onset latency

A change was reported, but the comparison could not be confirmed.

Review · Unknown intervention · Patient group

Analysis coverage and paper counts

1 paper · 1 measured outcome

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

morning sleepiness

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

overall subjective sleep quality score

The study needs further checking before its result can be interpreted.

Meta-analysis · Unknown intervention · General population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

sleep duration

The study needs further checking before its result can be interpreted.

Animal study · indirect · Ingredient combination · Unspecified population

This finding comes from animal or cell research. It does not establish the same effect in people.

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

sleep duration

The study needs further checking before its result can be interpreted.

Animal study · indirect · Separable contribution · General population

This finding comes from animal or cell research. It does not establish the same effect in people.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

sleep efficiency

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

sleep latency

The study needs further checking before its result can be interpreted.

Controlled study in people · Single ingredient · General population

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

sleep onset latency

The study needs further checking before its result can be interpreted.

Animal study · indirect · Ingredient combination · General population

This finding comes from animal or cell research. It does not establish the same effect in people.

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

sleep onset latency

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

sleep problems

The study needs further checking before its result can be interpreted.

Controlled study in people · Single ingredient · General population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Sleep quality

The study needs further checking before its result can be interpreted.

Other evidence · Single ingredient · Patient group

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

subjective daytime dysfunction

The study needs further checking before its result can be interpreted.

Meta-analysis · Unknown intervention · General population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

subjective sleep onset latency

The study needs further checking before its result can be interpreted.

Meta-analysis · Unknown intervention · General population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

total sleep time

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Unspecified measured outcome

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · Unspecified population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Unspecified measured outcome

The study needs further checking before its result can be interpreted.

Other evidence · Unknown intervention · Unspecified population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Cognition

What the research found

Attention

The study needs further checking before its result can be interpreted.

Review · Single ingredient · Patient group

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

attention on a switch task

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

cognitive function

The study needs further checking before its result can be interpreted.

Review · Unknown intervention · General population

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Review overlap with primary papers is unknown; counts stay separate.

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

reaction time to attention tasks

The study needs further checking before its result can be interpreted.

Controlled study in people · Single ingredient · General population

Within-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Rey-Kim memory quotient

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · Patient group

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

speed and accuracy of performance of the attention-switching task

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

susceptibility to distracting information in the memory task

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

total cognition composite

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · Patient group

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

total cognition composite

The study needs further checking before its result can be interpreted.

Controlled study in people · Single ingredient · Patient group

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Glucose and metabolic health

What the research found

Body weight

The study needs further checking before its result can be interpreted.

Animal study · indirect · Single ingredient · Unspecified population

This finding comes from animal or cell research. It does not establish the same effect in people.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

muscle glycogen

The study needs further checking before its result can be interpreted.

Animal study · indirect · Single ingredient · Unspecified population

This finding comes from animal or cell research. It does not establish the same effect in people.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Blood lipids

What the research found

serum levels of cholesterol

The study needs further checking before its result can be interpreted.

Animal study · indirect · Single ingredient · General population

This finding comes from animal or cell research. It does not establish the same effect in people.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

triglycerides

The study needs further checking before its result can be interpreted.

Animal study · indirect · Single ingredient · General population

This finding comes from animal or cell research. It does not establish the same effect in people.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Blood pressure and vascular health

What the research found

blood-pressure increases

The study needs further checking before its result can be interpreted.

Controlled study in people · Single ingredient · General population

Within-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Digestion and gut health

What the research found

intestinal inflammation

The study needs further checking before its result can be interpreted.

Animal study · indirect · Single ingredient · General population

This finding comes from animal or cell research. It does not establish the same effect in people.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Exercise performance

What the research found

Unspecified measured outcome

The study needs further checking before its result can be interpreted.

Controlled study in people · Unknown intervention · Unspecified population

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Fatigue and energy

What the research found

self-reported tiredness

The study needs further checking before its result can be interpreted.

Controlled study in people · Ingredient combination · General population

Several ingredients were used together. This does not establish the effect of this ingredient alone or synergy.

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Immune and respiratory health

What the research found

splenic organ index

The study needs further checking before its result can be interpreted.

Animal study · indirect · Single ingredient · General population

This finding comes from animal or cell research. It does not establish the same effect in people.

The comparison could not be confirmed.

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

Nutrient status

What the research found

Unspecified measured outcome

The study needs further checking before its result can be interpreted.

Controlled study in people · Single ingredient · Unspecified population

Between-group comparison

Analysis coverage and paper counts

1 paper · 1 measured outcome

1 papers held from direction counts

Direction counts are distinct papers within each row. Outcome contributions count endpoint results, so one paper may contribute more than once.

How to read research findings

How should I read research findings?

Research guides

Side effects and combination findings

Findings from this ingredient alone are shown separately from those involving another supplement or medication.

Caution findings
0
Findings from individual and combined use, plus reviewed cautions
Key precautions
No combination cautions are available to show in the current data. This does not guarantee safety.
Review 1 combination findings and 0 findings that outperformed an ingredient alone.
These findings were reported in studies. They do not predict an individual's experience.

Reported improvements with combinations

Combination findings are grouped by how the study compared them. This is not a recommendation to combine ingredients.

Combinations with reported improvement

The combination showed improvement, but each ingredient's contribution is unclear.

CaffeineL-theanine combined with caffeine significantly reduced caffeine-induced tachycardia (17% vs 92%) and state anxiety compared to caffeine alone.