Love Your Coffee Piping Hot? It May Raise Your Esophageal Cancer Risk

• Researchers have found a possible link between drinking very hot drinks and esophageal cancer.
• Drinking coffee or tea at too high a temperature was associated with a threefold risk.
• Experts advise allowing your hot beverage to cool before drinking.
• Avoiding other esophageal cancer risk factors like smoking and drinking heavily may matter more.

Do you need a cup of coffee to get your morning started? Or maybe you prefer to quietly sip your tea on the patio? Whatever hot beverage you enjoy, you may want to reconsider the temperature.

According to a new large study, drinking your tea or coffee too hot could increase your risk of a dangerous type of cancer.

Researchers looked at almost 1 million adults in the United Kingdom and found that those who preferred their drinks “very hot” were three times more likely to develop squamous cell carcinoma (SCC), a common form of esophageal cancer. 

The findings, published in the International Journal of Cancer on September 8, further suggest that drinking six or more hot beverages a day was associated with a higher risk of SCC.

However, it wasn’t all bad news. Simply lowering the temperature of your drinks might prevent many cases of this deadly cancer.

This research is the largest study to date on this topic and highlights a simple way to potentially reduce the risk of a serious, often fatal cancer. 

By choosing to drink hot beverages at lower temperatures and possibly reducing the number of hot drinks consumed daily, people may be able to protect themselves from developing this disease.

Effects of drink temperature on esophageal cancer risk

To understand how hot drinks affect cancer risk, scientists studied two large groups of UK adults: the Million Women Study and the UK Biobank. 

Together, these two studies included nearly 1 million people, ages ranging from 37 to 73.

Participants were asked how they liked their hot drinks — tea or coffee — by choosing from options like “warm,” “hot,” or “very hot.”

They also reported how many cups they drank daily, which the researchers divided into two groups: fewer than six cups and six or more cups per day.

The researchers then tracked these participants for over a decade, monitoring who developed esophageal cancer. 

This cancer has two main types: squamous cell carcinoma (SCC) and adenocarcinoma (AC). 

Using health records linked through the National Health Service (NHS), the team identified new cancer cases and analyzed the risk linked to drinking temperature and frequency.

Statistical methods called Cox proportional hazards models helped estimate the relative risk (RR) of developing cancer based on drink preferences, while adjusting for other factors like age, smoking, alcohol use, and body measurements. 

The results from both studies were combined to get a clearer picture of the risks across the U.K. population.

‘Hot’ and ‘very hot’ drinks linked to higher SCC risk

During an average follow-up of about 14 years in the Million Women Study and 11 years in the UK Biobank, there were 2,348 new esophageal cancer cases: 1,045 SCC and 1,303 AC.

The biggest finding was that people who drank their hot beverages at a “very hot” temperature had more than three times the risk of developing SCC compared to those who drank at a “warm” temperature. Specifically, the pooled relative risk was 3.17, meaning a 217% increase in risk. 

Those who preferred “hot” (but not very hot) drinks also had a higher risk, nearly double that of warm drinkers.

However, these temperature differences did not affect the risk of adenocarcinoma (AC), the other common type of esophageal cancer. The risk for AC remained about the same regardless of drink temperature.

The frequency of hot drink consumption also mattered. Participants who drank six or more hot drinks daily had a 71% higher risk of SCC compared to those who drank fewer than six, even after accounting for drink temperature. 

However, this pattern did not hold for AC, where the increase in risk was small (19%) and less clear.

The researchers also found that the increased cancer risk linked to very hot drinks was consistent across different groups of people, regardless of smoking status, alcohol intake, or whether milk was added to the drinks. This suggests that heat itself, rather than other factors, plays a key role in raising SCC risk.

The study also estimated that about 14% of SCC esophageal cancers in the UK could be prevented if people who currently drink their beverages “very hot” lowered their drink temperature to “hot.” This could translate into around 440 fewer cases of SCC each year in the UK alone.

These findings provide strong evidence that the temperature at which people drink tea and coffee significantly affects their health, particularly with respect to esophageal squamous cell carcinoma. 

According to the researchers, these results support the idea that long-term heat damage to the esophageal lining may lead to cancer.

Lowering drink temperature may help reduce risk

Sridhar Papaiah Susheela, MD, a radiation oncologist with ClinicSpots, emphasized that it’s not the coffee or tea itself that you need to worry about; it’s the excessive heat, which can trigger chronic inflammation in the esophagus. Sridhar wasn’t involved in the study.

“Unlike the mouth and tongue, which are highly sensitive to heat and will quickly warn you of a burn, the esophagus has fewer pain receptors,” he told Healthline. “People often swallow scalding liquids without realizing the tissue damage occurring on the way down.”

Over time, this chronic inflammation can create an environment that favors the development of cancer.

Sridhar further noted that the World Health Organization’s International Agency for Research on Cancer (IARC) has classified beverages above 65 degrees Celsius (149 degrees Fahrenheit) as “probably carcinogenic to humans.”

In practical terms, you’ll want to let your coffee or tea cool for at least three to five minutes before you drink it, so the temperature dips below IARC’s cut-off point.

“A simple clinical rule of thumb: if the beverage is hot enough to numb or burn the tip of your tongue, it is actively damaging your esophagus,” said Sridhar.

Sylvia Crowder, PhD, a nutrition researcher with the Moffitt Cancer Center, who wasn’t involved in this study, agreed with Sridhar’s recommendations.

However, she added that hot beverages are likely not the most important risk factor for most people.

“Established risk factors such as tobacco use, heavy alcohol consumption, obesity, particularly for esophageal adenocarcinoma, and chronic reflux also matter substantially,” she told Healthline.

Crowder advised focusing on these risk factors, especially smoking and heavy alcohol use.