Drinking beverages at very hot temperatures was linked to a higher risk of one type of esophageal cancer.
People drinking six or more hot drinks a day also had a higher risk of that cancer.
Simply allowing your coffee or tea to cool before drinking it could potentially reduce some of that risk.
For many people, coffee and tea are everyday staples. But new research suggests that how hot those drinks are when you consume them could matter when it comes to esophageal cancer.
The study, published in the International Journal of Cancer, looked specifically at two major types of esophageal cancer: squamous cell carcinoma (SCC) and adenocarcinoma (AC). Researchers wanted to better understand whether drink temperature and the number of hot drinks people consumed each day were associated with either type.
Previous research has connected very hot beverages — generally around 70°C (158°F) — with esophageal cancer. However, less was known about temperatures more typical of Western countries.
How researchers studied it
Researchers combined information from two large U.K. studies: the Million Women Study and the U.K. Biobank. Together, the analysis included 977,282 adults.
Participants reported how they preferred their hot drinks: warm, hot, or very hot. They also reported how many cups of tea and coffee they typically drank each day. Researchers grouped consumption into fewer than six drinks per day or six or more.
The participants were then followed for years using health records to identify new cancer diagnoses. The researchers ultimately identified 2,348 cases of esophageal cancer, including 1,045 cases of SCC and 1,303 cases of AC. The average follow-up lasted 14.2 years in the Million Women Study and 11.1 years in the U.K. Biobank.
What the results mean for consumers
The researchers found that people who preferred their drinks very hot had about three times the risk of developing esophageal SCC compared with those who preferred warm drinks. The researchers did not find the same relationship between drink temperature and adenocarcinoma.
Frequency mattered, too. After accounting for drink temperature, people who consumed six or more hot drinks per day had a 71% higher risk of SCC than those who drank fewer than six.
Based on their analysis, the researchers estimated that 14% of SCC cases could potentially be avoided if people who currently drink beverages at very hot temperatures instead drank them at temperatures described in the study as hot.
The findings don't mean that drinking coffee or tea automatically causes cancer. Instead, they point to drink temperature and frequency as potentially modifiable factors associated with SCC risk.
For consumers, one simple takeaway from the research is that giving your coffee or tea a little more time to cool may be worth considering.