Regularly sipping beverages such as tea and coffee at temperatures exceeding 65°C (149°F) significantly elevates the risk of developing oesophageal cancer, according to groundbreaking research involving nearly a million participants. The findings, published in the International Journal of Cancer by Oxford University researchers, represent the largest study to date establishing this connection. While the overall likelihood of developing the disease remains low, the analysis reveals that individuals consuming “very hot” drinks face a threefold increased risk compared to those preferring lukewarm beverages. The discovery underscores the importance of moderating beverage temperatures as a potential preventative measure.
Study Details and Methodology
The research, conducted across multiple UK centres, analysed data from 977,282 adults aged 40–69, tracking their hot beverage consumption habits and subsequent health outcomes over time. Participants were categorised based on their reported drink temperatures, with “very hot” defined as liquids at or above 65°C. The study found a clear correlation between scalding temperatures and heightened oesophageal cancer risk, particularly for squamous cell carcinomas. Lead author Dr Keren Papier highlighted that similar associations had previously been observed in South America, where the traditional hot herbal infusion mate is widely consumed. “Our work builds on global evidence, but this is the first large-scale study to quantify the risk in a UK population,” she noted.
The researchers emphasised that the mechanism behind this link likely involves thermal injury to the oesophageal lining. Repeated exposure to extreme heat may cause chronic inflammation and cellular damage, creating conditions conducive to cancerous transformation over time.
Temperature Thresholds and Consumption Habits
The study’s findings are particularly relevant for daily consumers of freshly brewed tea or coffee. A freshly boiled kettle reaches 100°C (212°F), and when poured into a cup, the liquid often remains between 90°C and 95°C—well above the danger threshold. Even adding milk, which slightly reduces temperature, may not sufficiently mitigate risk if the drink is still uncomfortably hot. The research also identified that consuming six or more very hot beverages daily amplifies the risk further.
Interestingly, commercial coffee cups often serve drinks at temperatures between 49°C and 60°C (120°F–140°F), deemed safe by industry standards. However, establishments offering “extra hot” options can exceed 82°C (180°F), a practice that could inadvertently contribute to health risks. The study suggests that avoiding drinks immediately after brewing—or waiting 5–10 minutes for cooling—could significantly reduce exposure.
Expert Advice and Broader Context
While the results are compelling, Cancer Research UK cautions against overinterpreting the data. “The absolute risk remains small,” explained Fiona Osgun, the charity’s representative. “Only one or two oesophageal cancer cases per 100 might be preventable through this behaviour change.” The organisation stresses that traditional risk factors such as smoking, heavy alcohol consumption, and poor diet remain far more impactful. “The most important steps to lower your risk are quitting smoking and moderating alcohol intake,” Osgun added.
For those concerned about hot drink temperatures, Cancer Research UK advises waiting until beverages are comfortably drinkable before consuming them. “There’s no need to measure the temperature—just take the time to let it cool naturally,” the charity recommended. The organisation also notes that oesophageal cancer symptoms, such as persistent heartburn, chest pain, or unintended weight loss, warrant prompt medical attention.
Why it Matters
This study’s magnitude and clarity highlight the need for public health messaging around seemingly innocuous habits. While the link between hot drinks and cancer may feel counterintuitive, the evidence is now robust enough to warrant behavioural adjustments. For millions who enjoy a morning brew, simply slowing down to allow drinks to cool could become a simple yet powerful act of self-care. Yet the broader takeaway lies in balancing personal choices with established risk factors. As Dr Papier notes, further research is essential to pinpoint precise temperature thresholds and understand individual susceptibility. In the meantime, this work serves as a vital reminder: sometimes, the hottest trends require the coolest approach.
