World Health Organization Says Very Hot Drinks May Cause Cancer

But drops coffee from list of possible carcinogens

The International Agency for Research on Cancer (IARC) has classified drinking very hot beverages as a probable carcinogen, something that probably causes cancer. IARC is the cancer agency of the World Health Organization. Very hot beverages refer to drinks hotter than 65 degrees Celsius, which translates to about 149 degrees Fahrenheit. In the US, coffee, tea, hot chocolate, and other hot beverages are usually drunk at temperatures lower than 149 degrees.

The studies that led IARC to classify drinking very hot beverages as a possible carcinogen mostly looked at maté, a type of tea that is traditionally drunk at very hot temperatures, mainly in South America, Asia, and Africa. The studies showed a link between the drink and esophageal cancer, but only when it was served at the traditional, very hot temperature.

In the US, major risk factors for esophageal cancer include use of tobacco products and drinking alcohol, especially when combined.

Coffee risk is downgraded

The same group of 23 scientists from 10 countries also evaluated available studies about coffee and cancer, and as a result, changed the way it classifies coffee. In 1991, IARC classified coffee as possibly causing cancer because of studies that linked coffee drinking to bladder cancer. Since then, however, new and better studies have become available. IARC now says it is no longer possible to determine whether drinking coffee causes bladder cancer.

In addition, IARC’s review of the studies has led it to conclude that coffee is unlikely to cause breast cancer, prostate cancer, or pancreatic cancer. Reduced risks were seen for liver cancer and endometrial cancer.

Many studies have been done to determine whether coffee can lower cancer risk because coffee beans contain antioxidants, which are thought to have a protective effect against cancer. But the overall results are not clear, and in many of the studies that showed a lowered risk, the benefit was found in people who drank 4 to 6 cups of coffee a day. Too much caffeine leads to health problems for some people, by interfering with sleep, triggering migraines, and causing digestive problems. And if cream and sugar is added, the extra fat and calories can contribute to weight gain – which increases the risk for many types of cancer.

Adding more fruits and vegetables to your diet is a healthier way to consume more antioxidants and may help lower your cancer risk.

IARC published its report online June 15, 2016 in The Lancet Oncology.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Carcinogenicity of drinking coffee, mate, and very hot beverages. Published online June 15, 2016 in The Lancet Oncology. First author Dana Loomis, International Agency for Research on Cancer Monograph Working Group, Lyon, France.

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