A study conducted by researchers at the University of Oxford indicates that drinking tea and coffee at temperatures above 65 degrees Celsius may significantly increase the risk of developing oesophageal cancer. The study found that individuals who regularly consumed beverages at these high temperatures were three times more likely to develop the disease compared to those who drank them at cooler temperatures. Additionally, consuming more than six hot drinks daily was associated with a 71 percent higher risk of oesophageal cancer, regardless of the temperature of the drinks.
The research specifically identified a link between these beverages and oesophageal squamous cell carcinoma (SCC), a particularly aggressive form of cancer that accounts for over 3,000 new cases annually in the UK. Studies suggest that approximately 20 percent of patients diagnosed with oesophageal cancer survive five years after their diagnosis, partly due to late-stage detection.
The researchers estimated that around 14 percent of oesophageal cancer cases diagnosed in the UK each year could be prevented if individuals allowed their hot drinks to cool before consumption. Experts believe that the heat from these beverages may damage cells in the upper part of the esophagus, where the cancer typically occurs.
Fiona Osgun, head of health information at Cancer Research UK, which funded the study, stated, "While the risk of being diagnosed with this cancer remains relatively low in the UK, this research does add to the evidence that drinking very hot drinks could increase the risk of oesophageal squamous cell carcinoma. There is however a simple step people can take – let a cuppa cool down a little before taking a sip."
The study analyzed data from nearly 980,000 UK adults who were monitored for over a decade. Participants reported their preferred drink temperatures – 'warm', 'hot', or 'very hot' – and the number of drinks consumed daily. The researchers compared this data with cancer diagnoses while accounting for other risk factors, including smoking, alcohol consumption, and obesity.
During the study, 2,348 participants developed oesophageal cancer, including 1,045 cases of SCC. Those who preferred 'hot' drinks were 1.7 times more likely to develop SCC than those who preferred 'warm' drinks, while the risk was more than three times higher for those who preferred 'very hot' drinks. No increased risk was observed for adenocarcinoma, the other primary type of oesophageal cancer.
Although the scientists did not measure the actual temperatures of the participants' drinks, previous research has indicated that beverages around 70 degrees Celsius are considered very hot, and the International Agency for Research on Cancer classifies drinks above 65 degrees Celsius as 'probably carcinogenic'. The researchers suggested that allowing drinks to cool could help prevent some cases of oesophageal cancer.
Dr. Keren Papier, the lead researcher at Oxford Population Health, noted that further research is needed to determine the specific drink temperatures associated with increased risk. In the UK, approximately 9,500 individuals are diagnosed with oesophageal cancer each year, with 7,900 fatalities attributed to the disease. Early symptoms of oesophageal cancer can often be mistaken for other conditions, leading to late diagnoses. Smoking, obesity, and alcohol consumption are also significant risk factors for the disease. Osgun emphasized that the most effective ways to reduce risk are to avoid smoking and limit alcohol intake.
Professor Muy-Teck Teh, an expert in molecular oral oncology at Queen Mary University of London, who was not involved in the study, cautioned that while the study shows a link, it does not establish a direct causal relationship between hot drinks and cancer.