Hot Coffee and Cancer Risk: What 65°C Means
A large Oxford study links very hot coffee and tea to a higher risk of oesophageal cancer, with 65 °C identified as a key threshold. Experts explain that the heat—not the beverage itself—causes tissue damage over time. Simple habits like waiting a few minutes for drinks to cool can reduce risk.
By Felo News Desk · Published
When the first sip of coffee or tea burns your tongue, you might think it’s just a fleeting discomfort. New research, however, suggests that the heat can have lasting consequences for your oesophagus, potentially raising the risk of cancer.
What the Oxford Study Found
Researchers at Oxford University followed almost one million middle‑aged adults in the UK. They discovered that people who routinely drank beverages at or above 65 °C (149 °F) had about three times the relative risk of oesophageal cancer compared with those who drank at lower temperatures. The study, published in the International Journal of Cancer, echoes similar findings from cultures where very hot drinks are everyday staples, such as the South American tradition of mate.
Why 65 °C Is the Critical Threshold
In the study, 65 °C was the cut‑off used to define a drink as “very hot.” Freshly boiled water can reach 100 °C, and tea poured immediately after boiling often stays between 90–95 °C. Coffee, depending on brewing method, can also exceed the 65 °C mark. A separate study of 118 young adults found that people usually did not perceive a drink as “too hot” until it reached about 70 °C, meaning a beverage could be dangerously hot without feeling intolerable.
Dr. Marwan Ibrahim, a specialist in family medicine at Medcare Medical Centre, explains that there is no single temperature at which a drink suddenly becomes harmful. Instead, 65 °C is the temperature at which evidence linking hot beverages to cancer becomes strong enough for the International Agency for Research on Cancer (IARC) to classify them as “probably carcinogenic to humans” (Group 2A).
How Heat Damages the Oesophagus
Each time a very hot drink passes through the oesophagus, it exposes the delicate lining to extreme heat. Over time, repeated thermal injury can lead to chronic inflammation, scarring, and cellular changes that may contribute to the development of oesophageal squamous cell carcinoma.
Dr. Jamila Khan, a gastroenterologist at Aster Cedars Hospital & Clinic, notes that the risk increases with the frequency of exposure. An occasional hot cup is not equivalent to a daily habit of drinking scalding beverages. She emphasizes that the condition remains relatively uncommon in many populations, but the risk factor is modifiable.
Practical Steps to Reduce Risk
Experts agree that the simplest way to lower exposure is to let hot drinks cool for a few minutes before drinking. Waiting until the temperature drops below 65 °C can significantly reduce thermal injury to the oesophagus. This small adjustment does not require giving up coffee or tea; it merely encourages a brief pause before consumption.
In addition to cooling drinks, individuals can:
- Use a thermometer to check beverage temperature if they are particularly concerned.
- Choose brewing methods that naturally produce cooler temperatures, such as cold brew for coffee.
- Limit the number of very hot drinks consumed per day, especially if they are part of a regular habit.
- Stay mindful of other risk factors like smoking, alcohol, and diet, which can compound the effect of hot beverage consumption.
What the Numbers Really Mean
The study’s “threefold increase” refers to relative risk, not absolute probability. Even with a higher relative risk, the overall chance of developing oesophageal cancer remains low for most people. Dr. Ibrahim stresses that the figure should not cause panic but rather highlight an avoidable risk factor that can be managed with simple habits.
Because oesophageal cancer is relatively rare in many regions, absolute risk remains modest. Nonetheless, the evidence is strong enough to advise caution, especially for those who regularly consume very hot beverages.
Next Steps and Ongoing Research
Researchers are continuing to investigate the biological mechanisms behind heat‑induced oesophageal damage. Future studies may refine the temperature threshold or identify additional factors that influence risk. In the meantime, health professionals recommend monitoring beverage temperatures and adopting cooling practices as a straightforward preventive measure.
For now, the takeaway is clear: if your first sip makes you wince, let it cool. A brief pause can help protect your oesophagus from the cumulative effects of heat over time.
Key facts
- Large Oxford study links very hot coffee/tea to higher oesophageal cancer risk.
- 65 °C is the threshold used to define “very hot” drinks.
- Heat—not the beverage itself—causes tissue damage over time.
- Cooling drinks for a few minutes can lower thermal exposure.
- The relative risk increase is modest; the condition remains uncommon.
- Simple habits can reduce a modifiable cancer risk factor.
Why it matters
Understanding the link between hot beverage temperature and cancer risk empowers individuals to make safer choices about everyday habits, potentially reducing a modifiable risk factor for oesophageal cancer.
Frequently asked questions
Is coffee itself carcinogenic?
No, the risk is associated with the temperature of the beverage, not the coffee itself.
How long should I wait for my coffee to cool?
Waiting 3–5 minutes usually brings the temperature below 65 °C, reducing risk.
Does this apply to tea as well?
Yes, the same temperature threshold and risk apply to both tea and coffee.
Sources
- [1] gulfnews.com — originally reported as “Hot coffee may raise oesophageal cancer risk: UAE doctors explain the 65°C threshold”
