Drinking very hot beverages increases the risk of developing oesophageal cancer, the largest study into the subject has found.
Financed by Cancer Research UK, researchers analysed data gathered from across the nation and established clear evidence connecting hot drinks to the disease, although the overall threat remains very minimal.
While prior studies have pointed to a similar correlation, this latest project provides the most thorough examination of the issue to date.
Participants who reported enjoying hot drinks faced roughly 1.7 times the cancer risk of those who preferred warm beverages.
That figure rose to approximately three times the risk for individuals who drank them very hot. Consuming six or more hot beverages daily also elevated the likelihood compared to drinking fewer than six per day.
Although exact temperatures went unrecorded in the study, the International Agency for Research on Cancer declared beverages above 65C as “probably carcinogenic” back in 2016.
Experts agree that adding cold milk or simply allowing drinks to cool before drinking can negate the risk.
The new study said the temperature at which coffee and tea is drunk in Western populations is estimated to be around 60C.
Fiona Osgun, head of health information at Cancer Research UK, said: “While the risk of being diagnosed with this cancer remains relatively low in the UK, this research does add to the evidence that drinking very hot drinks could increase the risk of oesophageal squamous cell carcinoma.
“There is however a simple step people can take – let a cuppa cool down a little before taking a sip.
“And the most important ways to reduce the risk of this cancer type are not smoking and cutting down on alcohol.”
Experts believe very hot drinks may damage the cells lining the oesophagus, which could increase the chance of cancer developing.
For the new study, experts from Oxford Population Health at the University of Oxford looked at data from around 980,000 adults by combining two large UK studies – UK Biobank and the Million Women Study.
The two main types of oesophageal cancer are adenocarcinoma and squamous cell carcinoma (SCC).
While drink temperature affected SCC risk in the study, there was no obvious impact on adenocarcinoma risk.HS
Overall, there are around 9,500 cases of oesophageal cancer in the UK every year.
People in the UK have around a 1% lifetime risk of being diagnosed with SCC.
Symptoms of oesophageal cancer
NHS
There are many possible symptoms of oesophageal cancer, but they might be hard to spot.
They can affect your digestion, such as:
- having problems swallowing (dysphagia)
- feeling or being sick
- heartburn or acid reflux
- symptoms of indigestion, such as burping a lot
Other symptoms include:
- a cough that is not getting better
- a hoarse voice
- loss of appetite or losing weight without trying to
- feeling tired or having no energy
- pain in your throat or the middle of your chest, especially when swallowing
- black poo or coughing up blood (although these are uncommon)
Dr Keren Papier, lead researcher and senior nutritional epidemiologist at Oxford Population Health, said: “International research has shown for some time that drinking beverages like mate at very high temperatures, as is typical in South America, is linked to increased risk of certain oesophageal cancers.
“What was less clear, was whether this also applied to the temperatures at which hot drinks are usually consumed in Western populations.
“This is now the largest study to look at that question in a UK population, where many people drink tea and coffee daily.
“It adds to existing evidence that drinking very hot drinks could increase the risk of oesophageal squamous cell carcinoma.
“More research is now needed to identify the exact drink temperatures linked to this increased risk.”
