Q & A Library

Yerba maté (also known simply as maté) is a tea made from the dried leaves of Ilex paraguariensis, an evergreen shrub in the holly family that grows in Central and South America. Maté (pronounced mah-tay) is most abundant in Paraguay, where it has been the centuries-old drink of the Guarani Indians as well as a traditional treatment for everything from fatigue to appetite control to a weakened immune system.

Maté contains xanthines, a class of chemical compounds that includes caffeine as well as theophylline and theobromine, the stimulants in tea and chocolate. Some scientists contend the primary type of xanthine in maté really is "mateine," a compound they say is chemically similar to caffeine but with a different molecular structure. Some South American researchers claim that mateine causes none of the ill effects of caffeine. For example, they say that unlike caffeine, yerba maté induces sleep and while it's a stimulant, it doesn't trigger the jitteriness that caffeine can cause. I find very little scientific support for this distinction, but you will certainly see health claims to that effect on packages of yerba maté and in advertisements for it. You may have seen maté marketed as a caffeine-free substitute for coffee and tea.

Some American scientists have found that yerba matédoes contain caffeine, but some people seem to tolerate it better than coffee or tea. Researchers at Florida International University in Miami are trying to determine why yerba maté bothers people less than other caffeine-containing beverages.

I consider yerba maté just another caffeine-containing tea. You can probably become dependent on it as you can on both coffee and tea. I drink yerba maté occasionally, but generally prefer green tea for its proven health benefits.

Andrew Weil, M.D.