During follow-up, 317 new cases of esophageal cancer were identified.
The IARC examined studies that mostly looked at mate, a type of tea that is traditionally drunk at very hot temperatures, mainly in South America, Asia, and Africa. However, according to this study, drinking very hot tea can increase the risk of oesophagal cancer.
Over a median of 10 years, the researchers studied more than 50,000 people between ages 40 and 75.
Oesophageal cancer is the 13th most common cancer in the United Kingdom, accounting for 3% of all new cancer cases (Cancer Research, 2015).
Drinking 700ml per day, which is roughly 2 or 3 cups, at the temperature of 60°C or higher was associated with a 90 percent higher risk of esophageal cancer. However, the next time you brew your daily cuppa or any other drink for that matter, you might want to give it some time to cool down, or it might increase your risk of cancer! However, they also recommend further studies on the reason behind the connection.
In 2016, the International Agency for Research on Cancer said that drinking any drink over 65 degrees Celsius makes it a carcinogen, or something likely to cause cancer.
The study said more research was needed on why exactly drinking very hot tea is associated with the higher risk of esophageal cancer. Stephen Evans, a professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine who was not involved with the research, believes the findings in the study have less to do with tea - or any other beverage or food for that matter - but with the heat.
"It is probably anything hot: microwaved jam has been known to cause oesophageal injury", he said.
Scientists then tested to see which of the tea drinkers developed esophageal cancer cells in their throat.
As of 2019, the American Cancer Society estimates a total of 17,650 new cases of esophageal cancer and 16,080 deaths from the disease.