Everything causes cancer: Hot tea edition

You know how at real Chinese restaurants all over town, the waiters always look at you funny when you ask for a glass of ice water because locals normally drink tea water about the temperature of the surface of the sun? Well you can laugh in their smug "Oh these foreigners and their addiction to cold drinks" faces - because now there's studies saying that hot tea, tea over the temperature of 70C, has been linked to oesophageal cancer!

The oesophagus is a muscular tube that carries food from the throat to the stomach. About 500,000 people worldwide die from oesophagus cancers, and of those oesophageal squamous cell carcinoma (OSCC) is the most common type.

While tobacco and alcohol have been linked to the development of this kind of cancer in Europe and America, scientists were previously baffled by why they were appearing in such large swaths of non-Western populations.

According to the BBC:

Golestan Province in northern Iran has one of the highest rates of OSCC in the world, but rates of smoking and alcohol consumption are low and women are as likely to have a diagnosis as men. Tea drinking, however, is widespread.

The University of Tehran researchers studied tea drinking habits among 300 people diagnosed with OSCC and compared them with a group of 570 people from the same area.

Nearly all participants drank black tea regularly, on average drinking over a litre a day.

Compared with drinking warm or lukewarm tea (65C or less), drinking hot tea (65-69C) was associated with twice the risk of oesophageal cancer, and drinking very hot tea (70C or more) was associated with an eight-fold increased risk.

The speed with which people drank their tea was also important.

Drinking a cup of tea in under two minutes straight after it was poured was associated with a five-fold higher risk of cancer compared with drinking tea four or more minutes after being poured.

Apparently, acts like pouring milk into your tea or waiting for it to cool helps lower the cancer risk. But next time your Chinese friend is about to down that scalding bowl of leaf water, stop him before it's too late!!!