People Who Drink Their Tea or Coffee Very Hot May Face Triple the Risk of One Type of Cancer

A million-person study points to repeated heat injury in the oesophagus.

A study of nearly one million UK adults found that people who preferred their tea or coffee “very hot” had about three times the risk of oesophageal squamous cell carcinoma, compared with those who drank them warm. The same link did not appear for the other major type of oesophageal cancer.

It’s the latest piece of evidence that adds to a long-running suspicion that repeated heat damage to the oesophagus, rather than anything in tea or coffee itself, may help drive cancer risk.

The Hotter the Drink, the Stronger the Signal

The Oxford team combined data from 510,112 participants in the Million Women Study and 467,170 in UK Biobank. Participants reported whether they liked hot drinks warm, hot or very hot, and how many cups of tea and coffee they drank each day. Researchers linked those answers with cancer records over average follow-ups of 14.2 and 11.1 years.

Among the 977,282 participants, 1,045 developed oesophageal squamous cell carcinoma (SCC) and 1,303 developed adenocarcinoma. After accounting for how many hot drinks people consumed, those who preferred them “hot” had a 69% higher SCC risk than warm-drinkers.

For “very hot” drinkers, the relative risk was 3.17 times as high. Drinking six or more hot drinks a day was independently associated with a 71% increase in SCC risk. No comparable temperature pattern appeared for adenocarcinoma.

The association was also similar whether people primarily drank tea or coffee. Adding milk did not clearly change it. Both findings point away from a particular ingredient and toward temperature itself.

Scientists have suspected this for years. Much of the earlier evidence came from South America, where people traditionally consume maté very hot. In a pooled analysis of 1,400 SCC cases across Argentina, Brazil, Paraguay and Uruguay, researchers found that cancer risk rose with cumulative maté consumption. But the association was substantially stronger among people who drank it at hotter temperatures.

In 2016, the International Agency for Research on Cancer classified beverages consumed above 65°C as “probably carcinogenic to humans.” Tea and coffee in Britain and the United States are commonly consumed at roughly 60°C.

×

Get smarter every day...

Stay ahead with ZME Science and subscribe.

Daily Newsletter
The science you need to know, every weekday.

Weekly Newsletter
A week in science, all in one place. Sends every Sunday.
No spam, ever. Unsubscribe anytime. Review our Privacy Policy.

Thank you! One more thing...

Please check your inbox and confirm your subscription.

Crucially, this study did not measure the drinks’ actual temperatures. Participants self-reported their preferences, so it cannot tell us that crossing a particular temperature suddenly triples risk.

“More research is now needed to identify the exact drink temperatures linked to this increased risk,” lead researcher Dr. Keren Papier told the BBC.

RelatedPosts

Tired? Try looking at a cup of coffee — new research says that’s enough to perk you up
How sound frequencies affect taste – will music replace sugar in your coffee?
Arabica coffee extinct in the wild in 70 years
How much coffee is too much? A new study shows 3 cups is maximum

Why One and Not the Other?

SCC arises from squamous cells—flat cells that line surfaces inside the body—in the upper two-thirds of the oesophagus, which hot liquid encounters on its way to the stomach. The researchers argue that repeated thermal injury could damage this protective lining and promote cancer-forming processes. Animal experiments have likewise found oesophageal injury after repeated exposure to very hot water. In mice, 70°C water damaged the oesophageal lining and, when combined with a chemical carcinogen, accelerated the development of premalignant lesions.

Earlier human evidence points the same way. In a prospective study of more than 50,000 people in northeastern Iran, researchers actually measured tea temperature. Tea consumed at 60°C or hotter was associated with a 41% higher SCC risk than tea below 60°C; people who described their tea as “very hot” had more than twice the risk.

A 2025 UK Biobank analysis had already found a similar temperature-and-dose pattern. The new study incorporates this dataset but adds the much larger Million Women Study and substantially more SCC cases.

The absolute risk remains small. Cancer Research UK estimates the lifetime risk of SCC in Britain at around 1%, while smoking and alcohol remain much larger established risk factors.

Assuming the temperature relationship is causal, the Oxford researchers estimate that about 14% of UK SCC cases—roughly 440 a year—might be prevented if people who currently drink beverages “very hot” turned the temperature down a bit.

The practical advice is simple: if your coffee or tea feels scalding, give it a few minutes.

The study was published in the International Journal of Cancer.