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Cognition/Performance/Mood

Guarana

Amazonian seed extract rich in caffeine that improves alertness and may reduce fatigue in adults seeking a plant-based stimulant.

Guarana
52
score
C
evidence
Caution
risk

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Use with caution

This supplement may interact with medications, medical conditions or sensitive populations. Review safety before use.

Quick Take

A natural caffeine source - works for alertness, but ordinary coffee is cheaper and better studied.

Guarana is a climbing Amazonian plant whose seeds are a concentrated source of caffeine, theobromine, tannins, and catechins. It works mainly by blocking adenosine receptors, which lowers perceived fatigue and increases vigilance; the tannin-rich seed matrix may slow caffeine release. It is commonly used in energy drinks and stimulant supplements. The best-supported benefits are improved alertness, reduced fatigue, and small gains in mood or mental performance. People needing short bouts of alertness or a plant-based caffeine source are most likely to notice it.

Potential benefits

01
Improves attention and alertness
02
May reduce fatigue
03
May improve mood
04
May improve memory and processing s

Protocol

Amount
200-800 mg standardized extract (≈30-160 mg caffeine)
Frequency
Once daily, or as needed for alertness
When
Morning or early afternoon; avoid within 8 hours of bedtime due to caffeine.

Onset Time

30-60 minutes; effects may feel smoother and longer than equivalent caffeine.

Who Should Consider

Healthy adults seeking a caffeine alternative
People who get stomach upset from coffee
Those wanting a plant-based stimulant
Shift workers or students needing short-term alertness

How It Works

Caffeine and other methylxanthines block adenosine receptors, reducing sleep pressure and increasing alertness, reaction speed, and perceived energy. The seed's tannins may slow gastric release and absorption, so effects can feel less abrupt than coffee or tablets.

Updated 5/19/2026

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