Graham Wise^{1, 2,}, Demetrio E. Santander³

Guayusa (Ilex guayusa Loes.) is a traditional herbal tea of western Amazon regions and an international commodity of increasing importance. Its consumption is rapidly growing in the USA and Canada, and the authorization of guayusa extract as a novel food in Europe signals further international market growth of this antioxidant and stimulant tea. However, little is known about the chemical composition of guayusa, despite much research on related Ilex species. There is an urgent need for a deeper understanding of the chemical composition of guayusa, to support assessments of its safety and its claimed nutritional value. This study follows the novel food assessment framework of the European Union Food Safety Authority, characterizing the proximate composition of guayusa and elucidating caffeine, amino acid and elemental components. It also evaluates potential microbial, mycotoxin and pesticide residue contaminants. The chemical composition of guayusa is analyzed in context with the related and well-characterized foods, yerba mate (Ilex paraguariensis A. St.-Hil.) and tea (Camellia sinensis L.). Guayusa’s moisture content, caffeine concentration, amino acid compliment and elemental profile, including heavy metals, present no greater risk to human health than the consumption of tea or yerba mate. It is also established that there is a low risk of mycotoxin, bacterial or pesticide residue contamination of guayusa. The chemical composition of guayusa presents no barrier to the authorization of guayusa as a novel food in accordance with European Union novel food guidelines.

guayusa, yerba mate, traditional food, novel food, antioxidant, stimulant, herbal tea