In British kitchens, a well-known ritual takes place most mornings. When the kettle boils and the tea bag is added, the mug is picked up almost instantly, hot and steaming, and carried to the table where the first sips are taken before common sense takes over. Perhaps 80 million times a day, this unremarkable scene is repeated nationwide. However, researchers at Oxford University now claim that this habit, which is quite common and very British, may carry a cancer risk that has not yet been widely recognized.
Data from almost a million UK adults who took part in the UK Biobank and the Million Women Study were used in the study, which was published in the International Journal of Cancer. The participants indicated whether they usually drank their hot beverages at “very hot,” “hot,” or “warm.” After that, researchers monitored their health outcomes for over 14 years. What surfaced was a pattern that is remarkable in its scope and clarity, even though it is not wholly unexpected to scientists who monitor worldwide oncology research. The risk of esophageal squamous cell carcinoma was about three times higher in those who drank their beverages extremely hot than in those who preferred them warm. Even those in the “hot” category, who sat in the middle, were almost twice as vulnerable.
Because those figures are easily misinterpreted in both directions, it’s worth taking a moment to consider them. The risk sounds concerning three times. And it is, in a way. However, the baseline risk of esophageal SCC, a relatively uncommon cancer, is approximately 1% over the course of a lifetime in the UK. Therefore, tripling a small number still results in a small number, and it’s crucial to preserve that context amid the clutter of a headline. In this regard, the researchers themselves exercise caution. Fiona Osgun, head of health information at Cancer Research UK, put it simply: reducing alcohol consumption and giving up smoking are the best ways for an individual to lower their risk of this cancer. Hot beverages play a role, but they coexist with much more significant ones.
However, since the association is not random, it is important to comprehend the mechanism underlying it. Repetitive passage of extremely hot liquid through the esophagus seems to harm the food pipe’s cellular lining. Something goes wrong after years and years of that heat stress—thousands of cups of tea, thousands of tiny insults to the same piece of tissue. Under stress, cells that continue to regenerate may eventually undergo mutation. Because it’s a slow, almost geological process, studies like this one must follow participants over a period of more than ten years in order to identify the signal.
Dr. Keren Papier, who oversaw the study at Oxford Population Health, has noted that earlier iterations of this conclusion originated from research conducted in South America and Asia, where the WHO’s International Agency for Research on Cancer had already identified the consumption of mate, a hot herbal beverage that is usually served well above 70°C, as a likely carcinogenic risk back in 2016. In Western Europe, where a cup of tea is hot but not quite mate-ceremony hot, the question of whether the same association persisted at somewhat lower temperatures remained unanswered. Although the precise temperature at which risk starts to increase has not yet been determined, this study indicates that the answer is in the affirmative. Although the line isn’t entirely clear, the IARC threshold of 65°C is a useful benchmark.
The research community believes that it will take some time for this finding to alter behavior, if at all. People have deeply ingrained, occasionally cultural, and sometimes emotional relationships with hot beverages. In the north of England, telling someone to let their tea cool for five minutes is advice that falls somewhere between minor annoyance and insult. However, this practical request is genuinely modest. It only takes a few minutes for a freshly poured cup of boiling tea to go from dangerous to comfortable, and adding milk helps, though it’s not a perfect solution. The researchers are not advocating for any kind of regulatory action or for coffee shops to alter their serving temperatures. Compared to that, the message is less complicated and disruptive.
With the support of the largest dataset yet gathered on the topic, this study brings a globally observed risk into a particularly British context, which may be its most lasting contribution. For more than ten years, almost a million people were followed. That isn’t a retrospective questionnaire distributed to a few hundred volunteers or a small pilot study. Even though it changes public behavior more slowly, this type of evidence base tends to change clinical recommendations. It’s difficult not to feel that the message has been quietly building for a while and that this study is just the loudest it has spoken thus far when you see how much research has been done in this area over the years. It’s unclear if people will pay attention or simply pick up their drinks and mugs.
FAQs
1. How much does drinking very hot beverages increase oesophageal cancer risk?
Very hot drinks are linked to roughly three times higher cancer risk than warm ones.
2. What temperature is considered dangerous for hot drinks?
The IARC flags beverages at or above 65°C as probably carcinogenic.
3. Which type of oesophageal cancer is linked to hot drinks?
Only squamous cell carcinoma shows the association, not adenocarcinoma.
4. How many people were included in the Oxford study?
Nearly 977,282 UK adults were tracked for over fourteen years.
5. What is the most effective way to reduce oesophageal cancer risk?
Not smoking and cutting down on alcohol matter far more than drink temperature.
