How Hot is Too Hot for Tea?
(Ivanhoe Newswire) – Hot tea is suppose to be, well, hot. But can it be too hot?
Yes, report Iranian researchers. Their study links drinking very hot tea with a significant increase in the risk for esophageal cancer.
The investigation took place in Golestan Province in northern Iran, where both tea drinking and esophageal cancer are common. The tea drinking habits of 300 people with esophageal cancer were compared to those of 571 healthy people from the same province.
People who drank their tea at 65 to 69 degrees centigrade were twice as likely to develop the cancer as those who drank tea at lower temperatures. Those who drank their tea at 70 degrees or above were eight times more likely to have the disease.
In keeping with these findings, the study also showed letting tea cool for two minutes after being poured was linked to a five times greater risk of esophageal cancer when compared to letting it cool for four minutes.
How does hot tea lead to esophageal cancer? In an accompanying editorial David Whiteman from the Queensland Institute of Medical Research in Australia, notes thermal injury has been suggested as a cause of epithelial cancers, although he emphasizes more study is needed to draw a firm conclusion.
The good news in the Iranian study is tea drinking itself did not raise the risk of the cancer. People who drank more of the beverage were no more likely to have the disease than people who drank less. Researchers say the key is just to bring it down a notch when it comes to the temperature.
SOURCE: BMJ, published March 26, 2009