Guayusa tea is a caffeinated herbal beverage commonly consumed in South America, particularly in Ecuador. The herbal infusion is made from the leaf of a holly tree (Ilex guayusa) that is native to the Amazon rainforest.
Over the past few years, guayusa products have begun popping up in natural-foods stores and in cafés around the U.S. Often marketed as an alternative to coffee and energy drinks, caffeine-rich guayusa is said to provide a healthier energy lift.
At this point, however, we know very little about how drinking guayusa might influence our health. Studies investigating the health properties of guayasa are extremely limited and almost no studies have been performed on humans. So far, most of the claims for the drink’s health effects come from anecdotal evidence.
One small study published in Clinical and Translational Science was performed on 12 adult males. They compared the response of 12 adult men to caffeine from a green coffee extract, a guayusa leaf extract, and a synthetic caffeine. Researchers determined that the guayusa leaf extract may be less stimulating to the release of epinephrine (adrenaline) compared with the green coffee extract and synthetic caffeine.
Researchers speculate that these compounds may provide some level of protection against cancer, diabetes, obesity, heart disease, bacterial infection, and other illnesses, but more rigorous studies are needed to confirm these theories.
Possible Side Effects
Researchers who have investigated the chemical properties of guayusa have reported that it appears to present no greater risk to human health than existing teas such as green tea or yerba mate. However, they add that further investigation is needed.
Selection, Preparation, and Storage
Many tea companies sell guayusa, although technically it is not a "tea" because it does not come from the tea plant (Camellia sinensis) that produces green and black tea. However, the herbal infusion is popular enough to be sold in many tea shops and online.
To brew, experts suggest that you bring fresh, cold water to a boil. Then pour eight ounces of water over about two grams of leaves and steep for up to seven minutes depending on how dark you like your brew. Guayusa can also be used to make iced tea.
How is guayusa different than yerba mate?
Tea is made from the leaves of both plants and consumed as a coffee alternative. A key difference between guayusa and yerba mate is the flavor. Unlike yerba mate, which can bear a somewhat bitter taste, guayusa is regarded as smooth, earthy, and slightly sweet.
Frequently referred to as a “clean” source of caffeine, guayusa is said to offer “balanced energy. Proponents claim that compounds found in guayusa promote a slow, steady release of caffeine and—in turn—help prevent caffeine-related side effects.
The caffeine content in guayusa and in coffee can vary greatly according to the way it is manufactured and brewed. However, the caffeine in one cup of brewed guayusa is said to be comparable to the caffeine in a cup of coffee.
Does the farming and production of guayusa affect the health of the rain forest?
What are some other coffee alternatives that provide an energy boost?