New research links very hot tea and coffee with increased oesophageal cancer risk. Here is what the findings mean and how to drink beverages more safely.
People who regularly drink tea or coffee at very high temperatures may face an increased risk of a major type of oesophageal cancer, according to new research involving nearly one million adults.
The study examined beverage-temperature preferences and long-term health outcomes. It found that people who preferred very hot drinks had a higher risk of oesophageal squamous cell carcinoma than those who consumed warm or cooler beverages. Both temperature and frequency appeared important, although the research was observational and cannot prove that hot drinks directly caused cancer.
Scientists believe repeated heat exposure may damage cells lining the oesophagus. Over time, this irritation could make the tissue more vulnerable to harmful changes. The concern relates primarily to temperature rather than tea or coffee themselves.
The International Agency for Research on Cancer has previously classified drinking very hot beverages—generally above 65°C—as probably carcinogenic. Researchers therefore recommend allowing freshly prepared drinks to cool until they are comfortable rather than painfully hot.
Practical precautions include waiting several minutes after boiling, adding cooler milk or water where appropriate and avoiding repeated sips that burn the mouth or throat. A comfortable drinking temperature does not require abandoning tea or coffee.
The latest findings still have limitations. Participants reported their own temperature preferences, and researchers could not perfectly measure the temperature of every drink. Smoking, alcohol use and other factors also influence oesophageal-cancer risk.
Persistent swallowing difficulty, unexplained weight loss, chest discomfort or worsening indigestion should be assessed by a doctor. These symptoms can have many causes and do not automatically indicate cancer.
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