What are the traditional, historical, and cultural uses of yerba mate?

Yerba mate has been consumed in South America for hundreds of years, and the Indigenous Guarani peoples of Paraguay are considered the original discoverers of yerba mate. The plant was chewed on or brewed to prepare decoctions that were used primarily for their stimulant effects. Other traditional uses included the treatment of liver disease, arthritis and other inflammatory conditions, digestive disorders, and heart disease and to slow aging and suppress appetite.^[1] In the 16th century, Jesuit missionaries came to South America and began to cultivate and trade yerba mate, which contributed to the expansion of yerba mate consumption in other regions.^[2]

In South American cultures, yerba mate is often prepared in a vessel called a gourd to which dried or roasted leaves and stems are added and hot (not boiling) or cold water is poured in to fill the vessel. The gourd may be refilled multiple times until the leaves are fully extracted, and filtered straws called bombilla are used to drink the yerba mate, helping to avoid drinking the plant material.^[3] How yerba mate is prepared can vary between cultures. Chimarrão is prepared using dried green leaves and hot water. Tererê is also prepared using dried green leaves but with cold water. Mate tea is usually prepared with roasted leaves and either hot or cold water.^[2][1]