The short version
- A major study indicates that drinking beverages at 65 degrees Celsius or above triples the risk of esophageal cancer compared to consuming warm drinks.
- Researchers estimate that avoiding very hot liquids could prevent a small fraction of squamous cell esophageal cancer cases, although smoking and alcohol remain larger risk factors.
- Experts advise waiting for drinks to cool to a comfortable temperature before consumption, noting that even milky tea or coffee can retain dangerous heat levels.
New research from Oxford University indicates a significant association between the temperature of consumed beverages and the development of esophageal cancer. The study, which analyzed data from nearly one million middle-aged men and women, represents the largest investigation to date linking hot drinks to this specific type of cancer. Participants who regularly consumed tea or coffee at very high temperatures faced approximately three times the risk of developing cancer in the food pipe compared to those who drank their beverages warm.
The study defines 'very hot' as any liquid reaching 65 degrees Celsius or higher. This threshold is critical because steaming hot liquids can physically damage the cellular lining of the esophagus as they travel toward the stomach. The data revealed that consuming six or more of these high-temperature drinks per day further elevates the risk profile. While adding milk may slightly reduce the temperature, researchers caution that milky tea or coffee can still remain far too hot for safe consumption immediately after preparation.
Contextualizing the heat levels involved, tea brewed immediately after a kettle reaches a full boil sits near 100 degrees Celsius. Even after being poured into a cup, the temperature typically remains between 90 and 95 degrees Celsius, well above the identified risk threshold. For comparison, a separate study involving young adults tasting black coffee found that most participants only considered drinks too hot if they exceeded 70 degrees Celsius. This suggests a potential gap between consumer perception of 'hot' and the temperatures deemed safe by medical researchers.
The practical implications for daily habits are straightforward but require patience. Experts recommend waiting several minutes before drinking to allow beverages to cool to a safer temperature. Cancer Research UK, which funded the study, notes that it is difficult to specify an exact cooling time due to variables in cup material and ambient conditions. Instead, the charity advises consumers to wait until the drink feels comfortable on the lips rather than scalding.
Despite the clear statistical link, the absolute risk of developing esophageal cancer remains low for the general population. Squamous cell esophageal cancer is rare, affecting only a few thousand people annually in the UK, with a lifetime diagnosis risk of approximately 1 percent. Researchers estimate that if everyone stopped drinking very hot beverages, roughly one or two cases out of every ten could potentially be avoided. This highlights that while temperature is a modifiable risk factor, it accounts for a small portion of overall incidence.
It is important to place these findings within the broader context of esophageal cancer risks. Smoking and excessive alcohol consumption remain far more significant contributors to the disease than beverage temperature. Fiona Osgun from Cancer Research UK emphasized that the most effective strategies for reducing risk involve quitting smoking and limiting alcohol intake. The new data adds another layer to preventive health advice but does not diminish the importance of these established lifestyle factors.
The findings align with previous research conducted in South America, where the consumption of mate, a very hot herbal beverage, has been linked to similar cancer risks. Lead researcher Dr. Keren Papier noted that while the association is clear, more work is needed to pinpoint the exact temperature ranges that trigger cellular damage. The current study provides a broad benchmark but leaves room for future investigation into precise thermal thresholds.
For individuals concerned about their health, awareness of symptoms remains crucial. Signs of esophageal cancer can include persistent heartburn, indigestion, pain in the throat or chest, and unexplained weight loss. While the new research offers a clear warning against scalding hot drinks, it also reinforces the value of paying attention to bodily signals and maintaining overall healthy habits to mitigate cancer risk.
Sources behind this briefing
Go to the original reporting
- BBC News↗Very hot drinks may damage the food pipe and increase cancer risk
