Oxford University researchers have found that drinking tea or coffee very hot could triple the risk of oesophageal cancer, while hot drinks raise the risk by around 1.7 times compared with warm drinks. The study analysed the drinking habits of 980,000 Brits who took part in the UK Biobank and the Million Women Study.
Study Findings on Drink Temperatures
People who said they enjoyed hot drinks had around a 1.7 times higher risk of oesophageal cancer of the food pipe. Those who said they drank them very hot had around a three times higher risk compared with those who said they have drinks warm.
Having tea or coffee black could increase the risk as well, as does drinking herbal teas that do not contain milk. Experts advise letting these drinks cool a bit before taking a sip.
Expert Commentary and Background
Lead researcher Dr Keren Papier, senior nutritional epidemiologist at Oxford Population Health, said: "This is now the largest study to look at that question in a UK population, where many people drink tea and coffee daily. It adds to existing evidence that drinking very hot drinks could increase the risk of oesophageal squamous cell carcinoma (SCC)."
There are about 9,500 cases of oesophageal cancer in the UK every year with acid reflux and smoking being risk factors. Researchers believe very hot drinks may damage the cells lining the oesophagus which could contribute to cancer developing.
Risk Factors and Recommendations
The study showed consuming six or more hot drinks per day also pushed up the risk compared to drinking fewer than six. It did not record the temperature of drinks but in 2016 the International Agency for Research on Cancer classified very hot beverages as anything above 65C and ruled they "probably" increase risk of cancer.
The new study said the temperature at which coffee and tea is drunk in Western populations is estimated to be around 60C. Fiona Osgun, head of health information at Cancer Research UK, which funded the study, said: "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. And the most important ways to reduce the risk of this cancer type are not smoking and cutting down on alcohol."
Types of Oesophageal Cancer
The two main types of oesophageal cancer are adenocarcinoma and squamous cell carcinoma (SCC). While drink temperature affected SCC risk in the study, there was no obvious impact on adenocarcinoma risk. People in the UK have around a 1% lifetime risk of being diagnosed with SCC.
