Drinking tea or coffee at very hot temperatures triples the risk of developing oesophageal squamous cell carcinoma, according to a study published on September 26, 2026, in the International Journal of Cancer. Led by Dr Keren Papier, a senior nutritional epidemiologist at the University of Oxford’s population health department, the research analyzed health and beverage habits of nearly one million adults in the United Kingdom.
Temperature and Frequency Drive Oesophageal Cancer Risk
The analysis combined data from two long-running health initiatives, the Million Women Study and the UK Biobank, tracking a total of 977,282 participants for over a decade. During an average follow-up period of 14.2 years for the Million Women Study cohort and 11.1 years for the UK Biobank group, researchers recorded 2,348 new cases of oesophageal cancer, which included 1,045 squamous cell carcinoma (SCC) cases and 1,303 adenocarcinoma (AC) cases.
Participants reported their preferred hot drink temperatures as warm, hot, or very hot. Individuals who selected very hot carried a pooled relative risk of 3.17—representing a 217% increase—for oesophageal squamous cell carcinoma compared to those who drank beverages at a warm temperature. Participants who preferred hot drinks rather than warm ones faced a 69% higher risk.
Frequency of consumption also played a significant role. Drinking six or more hot beverages daily was linked to a 71% higher SCC risk compared to consuming fewer than six cups, regardless of the preferred temperature. However, neither high temperature nor high frequency showed a material association with adenocarcinoma risk, where increases remained small and inconclusive.
Biological Mechanisms of Thermal Injury
Researchers attribute the elevated SCC risk to repeated thermal injury. Consuming liquids at high temperatures scalds the mucosal lining of the oesophagus continually over years, impairing the tissue’s ability to repair itself. Over time, this damage prompts cells to divide in ways that elevate carcinogenic potential.
These tumors typically develop in the upper two-thirds of the oesophagus, the segment that absorbs the initial contact of hot liquids. Animal studies cited by the researchers demonstrated that water heated to 70°C produced early lesions and tissue damage in test subjects, whereas lower temperatures did not trigger similar effects.
The International Agency for Research on Cancer classified hot drinks at or above 70°C as “probably carcinogenic to humans” in 2016. The latest UK findings align closely with prior studies conducted in Asia, Africa, South America, and the Middle East regarding mate and tea consumption at high temperatures.
Public Health Recommendations and Prevention
The research team adjusted their statistical models for smoking, alcohol use, physical activity, and body measurements to isolate the effects of temperature and frequency. The findings suggest that modifying beverage habits could prevent a substantial portion of cases.
“The fact that we observed a clear trend in risk across self-reported temperature categories suggests that further limiting the temperature at which individuals consume their drinks to something well below average for this population may well avoid an even greater proportion of SCC cases,” the study authors noted.
Fiona Osgun, head of health information at Cancer Research UK, which funded the work, advised consumers to let beverages cool naturally. “It’s difficult to put an exact time on how long a hot drink should be left to cool. But if you’re worried, we’d suggest just waiting until it’s comfortable to drink rather than drinking it while it’s still very hot,” Osgun stated.
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