For anyone who’s ever burned their tongue on a steaming cup of coffee, know this: A new review published by the World Health Organization (WHO) says drinking very hot drinks can increase your risk of developing cancer over time, CNN reports.

Specifically, the review, conducted by a panel of 23 experts at WHO’s International Agency for Research on Cancer found that drinking beverages above 149 degrees Fahrenheit—somewhere between how hot water is when it comes out of the tap and boiling water—is “probably carcinogenic to humans,” researchers said. The reason? Small scald burns in the esophagus can significantly increase cancer risk in the digestive tract in the long term.

For the study, scientists reviewed all available data on the carcinogenicity of a wide array of hot drinks, including coffee, tea, maté (a caffeinated leaf brew commonly consumed in South America) and other beverages. Researchers found no conclusive evidence for any cancer-causing effects when the drinks were served at warm or cool temperatures and suggested the drinks themselves were not carcinogenic.

But scientists did find significantly higher esophageal cancer rates in places where drinks are traditionally served at very high temperatures—such as China, Iran, Turkey and Brazil—when compared with places such as Europe and North America. Typically, in these areas of the world, people don’t serve their beverages so hot. What’s more, researchers noted that the increased cancer risk from exposure to scorching drinks in these areas was comparable to that from a number of known carcinogens, including lead, gasoline and exhaust fume exposure.

So how hot should you drink your coffee? Well, experts suggest that if your beverage is too hot to keep a finger in for five seconds, you shouldn’t drink it quite yet.


Did you know that the amount of heat used when barbecuing creates the formation of cancer-causing chemicals in the charred meat? Click here to learn how this happens.