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158 herbs, nutrients, and compounds. What the science says, what tradition knew, and what to watch for. Founding members keep this running.

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FATIGUE & RECOVERY

Yerba Mate

Ilex paraguariensis

also known as maté

Moderate (energy, antioxidant)

Yerba Mate — Köhler 1887 botanical illustration

Leaves from a South American holly tree, traditionally drunk as a shared social beverage from a hollowed gourd through a metal straw across Argentina, Uruguay, Paraguay, and southern Brazil. Yerba mate contains caffeine alongside other gentler stimulants, giving it a different feel than coffee — energizing without quite the same jittery edge for most people.

Provides caffeine for energy and mental focus — typically 30 to 50 mg per cup, less than coffee
Contains theobromine (the same compound in chocolate) and theophylline, which add to the energizing effect more gently
Rich in antioxidants — particularly chlorogenic acids and saponins
May modestly support healthy cholesterol and blood sugar
Traditionally used to suppress appetite, with some modern evidence
Long traditional South American social use as a daily beverage shared from a single gourd in groups

Caffeine content can disrupt sleep, raise blood pressure, and worsen anxiety in sensitive people

Heavy long-term consumption of very hot mate (drunk near boiling temperature, as is traditional) is associated with increased risk of esophageal, mouth, and bladder cancers — likely due to thermal injury and the polycyclic aromatic hydrocarbons formed during traditional smoke-drying of the leaves

Consuming mate at moderate temperatures and choosing leaves dried without smoke reduces this concern significantly

Use caution with stimulant medications — additive effects

Use caution with MAOI antidepressants

Skip with severe anxiety, insomnia, or arrhythmias

Limit during pregnancy due to caffeine

Drink mate at moderate temperatures, not near-boiling, for daily safety

Memorial Sloan Kettering About Herbs · EMA Herbal Medicinal Product Monographs · American Botanical Council HerbMedPro · Memorial Sloan Kettering About Herbs · EMA Herbal Medicinal Product Monographs · American Botanical Council HerbMedPro

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