⏱ 2 min read
The Short Version
Sipping "very hot" beverages can triple your risk of esophageal cancer by causing repeated thermal damage to your cells. While the absolute risk remains low, letting your brew cool could prevent hundreds of cancer cases every year.
Preferring your tea or coffee “very hot” may triple your risk of developing oesophageal squamous cell carcinoma (SCC), according to a massive study of nearly one million UK adults. This finding suggests the danger lies not in caffeine or tannins, but in the repeated thermal damage caused by liquid that is too hot.
Both findings point away from a particular ingredient and toward temperature itself.
Thermal Injury and Cellular Damage
The Oxford research team combined data from the Million Women Study and the UK Biobank, following 977,282 participants over an average of 12 years. While researchers relied on self-reported preferences rather than precise thermometer readings, the patterns were unmistakable: “hot” drinkers saw a 69% increase in SCC risk, while “very hot” drinkers faced a relative risk 3.17 times higher than those drinking warm beverages. Both findings point away from a particular ingredient and toward temperature itself.
This link has long been suspected through studies involving South American maté consumption and a prospective study in Iran where measured temperatures above 60°C were associated with a 41% higher SCC risk. The biological mechanism appears to be repeated thermal injury to the squamous cells lining the upper two-thirds of the esophagus. Animal models have already demonstrated that exposure to 70°C water damages this protective lining; in mice, this heat-induced damage accelerated the development of premalignant lesions when paired with chemical carcinogens.
Assessing the Absolute Risk
While these percentages sound alarming, researchers emphasize that the absolute risk remains relatively low. Cancer Research UK estimates the lifetime risk of SCC in Britain at roughly 1%, noting that smoking and alcohol are much larger established drivers of the disease. However, the scale of the potential impact is significant; Oxford researchers estimate that about 14% of UK SCC cases—roughly 440 annually—could be prevented if people simply lowered their preferred beverage temperature.
Dr. Keren Papier, the lead researcher, noted that more work is needed to pinpoint exact temperature thresholds. As a reminder, the International Agency for Research on Cancer has previously classified beverages consumed above 65°C as “probably carcinogenic.” The practical takeaway: if your brew feels scalding, let it sit for a few minutes.
Do you prefer your coffee at a temperature that forces you to sip slowly, or do you lean toward the scald?
Questions & Answers
How does drinking very hot beverages increase the risk of esophageal cancer?
Drinking very hot liquids increases cancer risk by causing repeated thermal injury to the squamous cells that line the upper two-thirds of the esophagus. This consistent heat exposure damages the protective lining of the esophagus over time. Research using animal models has shown that water at 70°C can damage these cells, which may accelerate the development of premalignant lesions. Rather than being caused by caffeine or tannins, the danger stems from the physical temperature of the liquid itself.
What is the connection between beverage temperature and esophageal squamous cell carcinoma?
There is a significant link between consuming beverages at high temperatures and a higher risk of developing esophageal squamous cell carcinoma (SCC). A massive study of nearly one million UK adults found that individuals who prefer very hot drinks face a relative risk 3.17 times higher than those who consume warm beverages. While the absolute lifetime risk remains relatively low at approximately 1%, researchers estimate that lowering beverage temperatures could prevent around 440 cases of SCC in the UK annually.
Why are certain beverage temperatures classified as potentially carcinogenic?
Certain beverage temperatures are classified as potentially carcinogenic because of the cellular damage caused by extreme heat. The International Agency for Research on Cancer has previously classified beverages consumed at temperatures above 65°C as probably carcinogenic to humans. This classification is based on the biological mechanism where high heat causes thermal injury to the esophageal lining. Studies in other regions have also shown that measured temperatures exceeding 60°C are associated with a significantly higher risk of developing esophageal cancer.
What factors contribute most to the development of esophageal cancer?
While high beverage temperatures are a significant risk factor, smoking and alcohol consumption are much larger established drivers of esophageal cancer. Although drinking very hot coffee or tea can triple the risk of squamous cell carcinoma, the absolute risk for an individual remains relatively low. Researchers suggest that most cases are linked to these lifestyle factors, but they note that reducing the temperature of hot drinks could still prevent a substantial number of annual cancer cases.
Originally reported by ZME Science.
