A recent study from the University of Oxford has highlighted a significant health concern for tea enthusiasts: regularly consuming "very hot" tea may considerably increase the risk of developing oesophageal squamous cell carcinoma (SCC). The extensive research, which tracked nearly a million individuals in the UK over 14 years, suggests that this common habit could triple the risk compared to drinking warm beverages.
The study, led by Dr. Keren Papier, a senior nutritional epidemiologist at Oxford’s population health department, asked participants to report their preferred drink temperatures as "very hot," "hot," or "warm." Researchers found a threefold higher risk of SCC among those who consumed "very hot" drinks compared to those who preferred "warm" beverages. Furthermore, individuals who drank six or more hot drinks daily saw a 71% increased risk of SCC, even after accounting for temperature preferences.
Understanding the Risk and Mechanism
Oesophageal squamous cell carcinoma (SCC) is one of the two primary forms of oesophageal cancer. The study found no similar increase in risk for oesophageal adenocarcinoma (AC). The proposed mechanism behind this increased risk is thought to be heat damage to the cells lining the oesophagus, also known as the food pipe, which can lead to cellular changes over time.
These findings resonate with earlier international studies conducted across Asia, Africa, South America, and the Middle East. These prior investigations similarly linked the consumption of tea or mate at temperatures of 70°C or above to a higher incidence of oesophageal cancer. The International Agency for Research on Cancer (IARC) previously classified hot drinks in 2016 as "probably carcinogenic to humans," identifying them as a probable cause of oesophageal cancer.
Expert Advice and Study Limitations
Health authorities could play a role in encouraging people to adopt safer drinking habits, such as allowing beverages to cool before consumption. Researchers estimated that a substantial number of SCC cases in the UK—approximately one in seven—could potentially be prevented if individuals who drink "very hot" beverages switched to merely "hot" temperatures.
Fiona Osgun, head of health information at Cancer Research UK, advised that there is no precise cooling time, but emphasized waiting until a drink is comfortable to consume. However, Professor Muy-Teck Teh of Queen Mary University of London cautioned that a limitation of the study was its reliance on self-reported temperature preferences, which might introduce variability due to individual sensitivity to heat. It's also important to remember that smoking and alcohol consumption remain significant, well-established risk factors for oesophageal cancer.