Summary Oesophageal SCC is the most common form of oesophageal cancer worldwide. The oesophagus, or food pipe, is the muscular tube that carries food and drinks from the mouth to the stomach.
Drinking very hot tea and coffee could significantly increase the risk of oesophageal cancer, according to a large UK study involving nearly one million people.
The study, published in the International Journal of Cancer, found that people who preferred their hot drinks “very hot” had more than three times the risk of developing oesophageal squamous cell carcinoma (SCC), compared with those who preferred their drinks warm.
Oesophageal SCC is the most common form of oesophageal cancer worldwide. The oesophagus, or food pipe, is the muscular tube that carries food and drinks from the mouth to the stomach.
Researchers from the University of Oxford analysed health data from nearly 980,000 middle-aged adults who were part of the Million Women Study and UK Biobank. Participants reported whether they preferred their drinks warm, hot or very hot, as well as how many hot drinks they consumed each day.
During the study’s follow-up periods, 2,348 cases of oesophageal cancer were recorded.
The researchers found that cancer risk increased as the preferred temperature rose. Those who preferred hot drinks had almost twice the risk compared with people who chose warm drinks, while those who preferred very hot beverages faced more than three times the risk.
The amount consumed also appeared to matter. After accounting for temperature, people who drank six or more hot beverages a day had a 71% higher risk of oesophageal SCC than those who drank fewer than six.
The International Agency for Research on Cancer classified very hot beverages as “probably carcinogenic” in 2016, defining them as drinks consumed above 65 degrees Celsius (149 degrees Fahrenheit).
Lead author Keren Papier, a senior nutritional epidemiologist at Oxford Population Health, said the study provides evidence from typical drinking habits in the UK and suggests that how people consume hot drinks may matter.
However, researchers stressed that the findings do not prove that hot drinks directly cause cancer. Participants reported their perceived drink temperatures, and the study could not determine the exact temperatures of the beverages.
Professor Muy-Teck Teh of Queen Mary University of London said the results should therefore be viewed as “robust associations rather than causal proof”.
Experts say there is a plausible explanation for the association, as very hot liquids can damage cells lining the oesophagus and cause inflammation.
The overall risk of oesophageal cancer remains relatively low. Researchers suggest that people concerned about the findings can simply allow their drinks to cool before consuming them.
Smoking remains a major risk factor for oesophageal SCC, while alcohol consumption and other environmental factors may also contribute to the disease.
