Guarana

Best for

Sharpen focus and mental stamina

Barely detectable · 125–1080 mg/day for 1 weeks · 3 studies , n=104

6 papers · 1 claim · 13 outcomes scored · 1 positive

Outcomes

What guarana actually does, by outcome

Each row is one outcome with effect size, evidence base, the dose that worked in trials, and time to first effect. Magnitude tiers come from native-unit MCID where available, Cohen's d otherwise.

Outcome Effect size Evidence Dose Weeks Rank

Sharpen focus and mental stamina Barely detectable

Concentrate longer, resist distraction, and stay mentally sharp through demanding tasks.

3 RCTs n=104 125–1080 mg 1 wk

23706111·36146946·38931247

trivial

3 RCTs n=104

125–1080 mg

1 wk

—

Outcome	Effect	Evidence	Dose	Weeks	Rank
Sharpen focus and mental stamina Barely detectable	trivial	3 RCTs n=104	125–1080 mg	1 wk	—

Buy well

Recommended Guarana products

Real products that dose Guarana where the research does, in a clean formulation, from brands we've audited. We only list ones we'd stand behind.

Chosen for adequate Guarana dosing vs. the studied range, a clean formulation (grade A–C), and independent brand-quality audits. Not sponsored.

Risk profile

Adverse events and known drug interactions

Safety events

gastrointestinal discomfort mild

nausea mild

increased stool frequency / abdominal cramps mild

cardiovascular_adverse_events

Drug interactions

other moderate increases effect

Sources

Generated August 14, 2026

Guarana

What guarana actually does, by outcome

Recommended Guarana products

Adverse events and known drug interactions

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