Acute Effects of Naturally Occurring Guayusa Tea and Nordic Lion’s Mane Extracts on Cognitive Performance

Authors:
La Monica MB, Raub B, Ziegenfuss EJ, Hartshorn S, Grdic J, Gustat A, Sandrock J, Ziegenfuss TN.

Journal:
Nutrients, 2023
DOI: 10.3390/nu15245018

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Study Design

Randomized, double-blind, placebo-controlled, three-arm crossover trial.

Participants

40 healthy men and women (ages 18–50) who habitually consumed ≤240 mg caffeine/day.

Intervention

Participants consumed on separate visits:

• 1,000 mg of organic Nordic Lion’s Mane extract (Hericium erinaceus) fruiting bodies (single dose)
• 650 mg of guayusa extract (AmaTea® Max; 130 mg caffeine + 30% chlorogenic acids)
• Placebo (maltodextrin)

Each participant received all three interventions in a Latin Square crossover design. Measurements were taken at baseline, 60 min, and 120 min post-ingestion.

Outcome Measures

• Neuropsychological tests (Go/No-go, N-Back, Serial 7s)
• Visual Analog Scales (mood, focus, clarity, productivity, stress tolerance)
• Subjective Happiness Scale
• Vital signs (blood pressure, heart rate)

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Summary

This study evaluated the acute cognitive effects of single doses of Lion’s Mane extract and guayusa in healthy adults. Both supplements improved certain aspects of cognitive performance:

• Lion’s Mane extract significantly improved reaction time in the Go/No-go task and N-Back working memory task at 120 minutes, along with increased perceived happiness.
• Guayusa extract led to broader improvements in cognitive performance (reaction time, working memory, concentration, productivity, focus, mood, and stress tolerance), but also slightly elevated systolic and diastolic blood pressure.
• No serious adverse effects were reported for either supplement.

Overall, Lion’s Mane demonstrated modest but measurable acute improvements in reaction time, working memory, and subjective well-being.