Guayusa is not related to the camellia sinensis (tea) plant. It is one of three caffeinated holly trees that exist in the world, and is a distant cousin of Yerba Maté. Guayusa leaves have a smooth ribbed edge, similar to the distinctive shape of a holly tree leaf (but without the spikes). Very large in size, guayusa leaves can reach over 15 cm in length.
In addition to caffeine, guayusa also contains theobromine, the stimulant found in chocolate, and L-theanine found in green tea that has been shown to reduce physical and mental stress. The caffeine content in guayusa is around 3% by dry weight, and guayusa contains all of the essential amino acids for humans and has a “high antioxidant activity,” with ORAC antioxidant values of 58μM per gram, compared to 28-29μM per gram for most green teas.