If you drink your tea the moment it's poured, or take your coffee 'extra hot', you may be pushing your risk of one type of serious cancer up by three times, according to the largest UK study of its kind.

Researchers at Oxford Population Health tracked 977,282 middle-aged men and women and found that people who described their tea or coffee as 'very hot' were around three times more likely to develop oesophageal squamous cell cancer than those who preferred it warm. Even 'hot' drinkers carried 1.7 times the risk.

That matters because tea and coffee are two of the most-consumed drinks in Britain, and most people have never thought twice about how hot 'too hot' actually is. Freshly boiled water is 100°C, and tea poured straight after still sits at 90°C to 95°C.

The findings, published in the International Journal of Cancer, come from the largest study to examine this link among Britons. Previous evidence came mainly from South America, Asia and the Middle East, where scalding drinks are more common.

Steaming Drinks and Cancer Risk

'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,' said Dr Keren Papier, the study's lead researcher.

'What was less clear was whether this also applied to the temperatures at which hot drinks are usually consumed in Western populations,' she said. Her answer: it does.

'This is now the largest study to look at that question in a UK population, where many people drink tea and coffee daily,' she said. 'It adds to existing evidence that drinking very hot drinks could increase the risk of oesophageal squamous cell carcinoma.'

The mechanism is thought to be repeated scalding of the oesophagus lining, which can trigger the kind of cell changes that eventually turn cancerous. One earlier study found a single large sip of 65°C coffee raised the temperature inside the food pipe by up to 12°C.

Drinking six or more hot drinks a day pushed the risk up further still. Milk barely changes the equation, cooling a drink only slightly, so a milky tea poured too soon can still sit well above the danger threshold.

Small Risk, Bigger Factors

Even so, oesophageal cancer stays rare. It is the UK's 14th most common cancer, with around 9,500 new cases a year, and about one in a hundred people will face it in their lifetime.

Researchers estimate that one or two in every ten of those cases could be avoided if people simply let their drinks cool. There is also a limit to how much temperature explains.

Squamous cell carcinoma, the form linked to heat, is less common in Britain than adenocarcinoma, which is driven mainly by smoking, obesity and acid reflux. Cancer Research UK, which part-funded the study, is blunt about where the bigger levers are.

Giving up smoking and cutting back on alcohol will do far more for your risk than waiting for your tea to cool. Symptoms are still worth knowing either way.

Heartburn, indigestion, pain or difficulty swallowing, and unexplained weight loss are the key warning signs. Persistent versions of any of them are worth a GP visit, regardless of how you take your tea.

The advice from researchers is almost insultingly simple: give it a few minutes. It will not undo a lifetime of habits, but it might be one of the cheapest changes on offer.

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