Consistently consuming tea or coffee at high temperatures can elevate the risk of cancers impacting the esophagus, the passage that transports food from the throat to the stomach. Research using data from over 450,000 UK Biobank participants discovered that individuals consuming eight or more cups of very hot tea or coffee daily were nearly six times more likely to develop oesophageal squamous cell carcinoma (ESCC) within an average follow-up of 12 years, compared to those who avoided hot drinks.
Participants were asked about their preferred temperatures for hot beverages. Approximately 17% chose “very hot”, 66.5% opted for “hot”, and 15.3% said “warm”. Women more frequently than men selected “very hot”, defined by researchers as exceeding 65°C.
An increased risk was also seen for people who drank more than eight cups per day.
The risk increased by 2.52 times for individuals consuming four or more very hot drinks daily, 3.67 times for four to six cups, and 4.75 times for six to eight cups.
As stated in the British Journal of Cancer, researchers concluded that tea and coffee drinkers in the UK preferring their drinks hot or very hot had increased ESCC incidence compared to those opting for warm beverages or abstaining from hot drinks altogether.
The experts noted that the biological explanation for this link between very hot drinks and risk of oesophageal cancer was unclear.
They further noted: “One theory suggests regular exposure to very hot drinks can cause cellular harm that may lead to esophageal cancer development.
“An animal study demonstrated that consuming very hot water (70°C) promoted tumor development in oesophageal hyperproliferative premalignant lesions in rats.”
A similar study in 2019 of people living in Iran found that people who drank tea at or above 60C had an increased risk of oesophageal cancer.
Cancer Research UK noted at the time that 60C was likely to be “a lot hotter than most cups of tea”.
The charity’s analysis added: “If you’re leaving your tea to cool for a few minutes before drinking it, even while it’s brewing, or adding cold milk, it’s unlikely that you’re increasing your risk of oesophageal cancer.”
