Does hot tea cause esophageal cancer?

There is nothing like a hot drink to perk you up in the morning, especially during the cold regions and seasons. And depending on cultural practices, hot beverage can be tea, coffee, milk or hot chocolate. Tea is supposed the second most popular beverage after water and most of the time it is imbibed hot.

Researchers from Iran and the UK looked at how tea drinking habits of a population is linked to risk of esophageal cancer. The province of Golestan in northern Iran is an area with an abnormally high incidence of oesophageal squamous cell carcinoma. Esophageal squamous cell carcinoma is the most common form o esophageal cancer. It is closely linked with tobacco use and alcohol abuse. In the Golestan province, the low prevalnce of these risk factors cannot explain why this region has the world’s highest incidence of this type of cancer. A similar pattern has been observed in a region in China.

The researchers looked at 48 582 participants in a cohort study. From these, 300 participants had histological proven cases of esophageal cancer and 571 matched neighborhood control cases were followed and interviewed on their tea drinking habits.

The tea drinking habits of the people in this province can be summarized as:

People in the province, on the average, drink tea at higher temperatures compared to neighboring areas.
Tea is consumed in large amounts, similar to amounts of water.
Tea consumption starts early in life and lasts for life.
98% of all study participants drank black tea regularly, with a daily average volume of more than a liter.
39.0% of participants drank their tea at temperatures less than 60°C
38.9% drank their tea at 60-64°C
22.0% drank their tea at 65°C or higher.

Statistical analysis shows that drinking hot tea or very hot tea (60°C and above) is associated with an increased risk for developing esophageal cancer.

In addition, the time duration between pouring the tea and drinking it seems to be inversely associated with esophageal cancer risk.

“…compared with drinking tea four or more minutes after being poured, drinking tea two to three minutes after pouring or less than two minutes after pouring (5.41, 2.63 to 11.1) was associated with a significantly increased risk. A strong agreement was found between responses to the questions on temperature at which tea was drunk and interval from tea being poured to being drunk.”

The study results suggests that drinking hot tea, a habit common in Golestan province, was strongly associated with a higher risk of esophageal cancer. However, it isn’t clear whether the association is simply due to the temperature of the drink or the combination of temperature and type of drink. Would drinking hot coffee or other hot beverage have a similar effect? This would definitely be an interesting topic to look into.

So how hot do you want your drink?