A large study found that drinking very hot tea or coffee is linked to a higher risk of esophageal squamous cell carcinoma (SCC). Source: sciencealert.com.
Key Findings from the Study
Researchers analyzed data from 977,282 people in the Million Women Study and UK Biobank.
Participants reported how hot they liked their drinks—such as ‘very hot,’ ‘hot,’ or ‘warm’—and how many cups of tea or coffee they drank daily.
Those who preferred ‘very hot’ drinks had a 3.17-fold higher risk of esophageal SCC than those who drank drinks ‘warm’.
People who liked their drinks ‘hot’ had a higher SCC risk than those who preferred ‘warm’ drinks.
Drinking six or more hot drinks a day was associated with an increased SCC risk compared to those drinking fewer than six, after adjusting for temperature.
The risk was the same for tea and coffee drinkers. Adding milk did not change the temperature-related risk.
Why Temperature Matters
The study shows a link, not a cause. It does not prove hot drinks lead to cancer.
Still, reducing drink temperature—even slightly—could prevent many cases of esophageal SCC.
The researchers suggest that changing from ‘very hot’ to ‘hot’ could potentially prevent a substantial number of SCC cases.
What the Science Shows
Animal studies show that 70°C water causes esophageal tissue damage and premalignant lesions.
Lower temperatures do not show these effects, suggesting thermal injury is the likely cause.
Since the risk is consistent across drinks and unaffected by milk, temperature—not ingredients—is the main factor.
Study Limitations
Participants reported drink temperature preferences, not actual temperatures.
No one measured how hot their drinks actually were in degrees Celsius.
Future research could use smart cups or sensors to collect real-time data.
Background: IARC’s 2016 Classification
In 2016, IARC classified beverages above 65°C as ‘probably carcinogenic to humans’.
This was based on mate, a South American drink often consumed at 70°C, linked to higher esophageal cancer risk.
This study shows similar risks for tea and coffee in Western populations, even at lower temperatures.
What’s Next in Research
Future studies may measure actual drink temperatures during consumption.
Public health advice might one day recommend cooling hot drinks to a ‘hot’ rather than ‘very hot’ level.
For now, the message is clear: how hot your drink is matters more than you think.
The findings are published in the International Journal of Cancer.
ScienceAlert fact-checked the article by Fiona MacDonald and edited it for clarity and accuracy.
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