The following is a statement authored by the American Specialty Tea Alliance’s Board of Directors.
First, it is important to know that the cancer risk exists when consuming any hot beverage, such as coffee, soup, hot chocolate, etc., not just tea. And second, know that the key word here is “hot” — the increased risk of esophageal cancer in the most recent study was only seen when tea was consumed at above 140F.
A 2016 International Agency for Research on Cancer (IARC) working group of 23 scientists met and concluded that drinking “very hot beverages” is “probably carcinogenic to humans.” Very hot was classified as temperatures above 149 degrees Fahrenheit (65 degrees Celsius) by the group.
The most recent study that spurred a flurry of media activity last week followed 50,000 people in Iran, where tea is typically prepared in a samovar and consumed at very hot temperatures.
The study concluded that consuming tea warmer than 140 degrees Fahrenheit (60 degrees Celsius) and at volumes greater than 700 ml of tea per day had a 90% higher risk of esophageal cancer, when compared to those who drank less tea and at cooler temperatures.
In our experience, consumption patterns for specialty tea result in tea being consumed at temperatures less than 140 degrees Fahrenheit and therefore do not pose a cancer risk per the studies.
When preparing specialty teas, the tea is typically steeped at temperatures well under boiling in a steeping vessel. Once the steeping process is complete, the tea is decanted and then served. The transfer from vessel to vessel, the lower starting temperature, and the use of thinner cups (rather than a thick coffee mug) all contribute to temperature reduction before being served.
Furthermore, the subtle nuances of the finest teas are better perceived by the palate at slightly cooler temperatures, so ensuring safety may also enhance your tea enjoyment.
To be sure that you are consuming tea at a safe temperature, we advise you to monitor your tea practice and take a temperature reading before consuming tea (or any hot beverage).