Recent research has revealed a concerning link between the consumption of very hot drinks and an increased risk of certain cancers, particularly oesophageal cancer. A study involving nearly half a million adults in the United Kingdom confirmed that individuals who regularly consumed drinks at temperatures exceeding 65°C faced significantly higher cancer risks.
The International Agency for Research on Cancer (IARC) classified drinking very hot beverages as “probably carcinogenic to humans” in 2016. This classification places hot drinks in the same risk category as consuming large amounts of red meat and exposure to emissions from indoor wood smoke. The agency’s findings indicate that it is the temperature of the beverages, rather than the drinks themselves, that poses the health risk.
Research indicates that drinking beverages at very high temperatures, particularly traditional herbal drinks like maté, which is consumed around 70°C, has been associated with a higher incidence of oesophageal cancer in regions such as South America. Studies in the Middle East, Africa, and Asia have similarly supported these findings, establishing a global concern regarding the risks of very hot drinks.
The recent study from the UK found that individuals who consumed eight or more cups of very hot tea or coffee daily were nearly six times more likely to develop oesophageal cancer compared to those who did not regularly ingest hot beverages. This alarming statistic highlights the potential dangers that come with the comfort of a hot drink.
The mechanism behind this increased cancer risk primarily involves the damage inflicted on the cells lining the oesophagus. Over time, habitual consumption of very hot drinks can lead to cellular damage, raising the likelihood of cancerous developments. This association has been supported by animal studies, which have shown that mice given water at 70°C were more prone to developing precancerous growths compared to those given cooler water.
Additionally, researchers suggest that the manner of consumption may also play a role in the risk. Drinking large quantities of hot beverages in a single sitting may cause more significant heat injury to the oesophagus. A study measuring oesophageal temperatures found that taking larger sips could raise internal temperatures by as much as 12°C.
So, what is considered a safe drinking temperature? While brewing temperatures for coffee often approach boiling, the optimal temperature for drinking coffee, according to a US study, is around 57.8°C. This temperature balances the risk of heat injury with the preservation of flavor.
To enjoy hot drinks safely, experts recommend allowing time for beverages to cool. A drink’s temperature can drop by 10–15°C within five minutes, making it safer to consume. Additionally, taking smaller sips can help test the temperature and mitigate the risk of oesophageal damage.
Vincent Ho, an Associate Professor and Clinical Academic Gastroenterologist at Western Sydney University, emphasizes the importance of moderation and awareness regarding hot drinks. This research serves as a vital reminder to enjoy hot beverages thoughtfully, considering both their comforting qualities and potential health risks.
This article has been republished with permission from The Conversation under a Creative Commons license. For further details, please refer to the original article.
