Yerba Mate

Yerba mate is generally understood to contain caffeine, so we do not treat it as a "caffeine-free herbal tea". We did not find a source we could read with its caffeine content, so treat it as a caffeinated drink and check the label. It is covered here as a related drink. What we could source is the cancer-risk finding about temperature.

Overview and identity

Maté is an infusion made from dried leaves of Ilex paraguariensis. It is consumed mainly in South America and to a lesser extent in the Middle East, Europe and North America, and is traditionally drunk very hot (about 70 °C), though it may also be consumed warm or cold. [1]

What IARC concluded (2016)

A working group of the International Agency for Research on Cancer (part of the WHO) evaluated coffee, maté and very hot beverages.

• Very hot beverages (above 65 °C) were classified as probably carcinogenic to humans (Group 2A) for cancer of the esophagus, based on limited evidence from epidemiological studies and limited animal evidence. Studies in places where tea or maté is drunk very hot found that esophageal cancer risk rose with drink temperature. IARC said the temperature, rather than the drink itself, appeared responsible. [1]
• Maté at temperatures that are not very hot was not classifiable as to carcinogenicity (Group 3); there was inadequate evidence for cold or warm maté. [1]
• Coffee was also not classifiable. [1]

The proportion of esophageal cancers linked to very hot drinks is not known. [1] This applies to any drink above 65 °C, including hot tea, so let drinks cool.

What we could not find

Proper evidence not found (in sources we could read) for yerba mate's caffeine content per serving, health benefits, interactions or safety in pregnancy. We make no claims for them. Treat it as a caffeinated drink.