Hot beverages can be harmful: WHO

The habit of drinking hot beverages might be linked to oesophageal cancer, according to a report issued by the World Health Organization (WHO) on Wednesday.

"Drinking hot coffee could be dangerous to your health, but apparently it's not the coffee, it's the hot," UN spokesman Stephane Dujarric told reporters here.

"The report issued by an international group of 23 scientists convened by the WHO found no conclusive evidence for a carcinogenic effect of drinking coffee, or mate," Dujarric said at a daily news briefing here. "But the experts did find that drinking very hot beverages can cause cancer of the oesophagus."

It is the temperature, rather than the drinks themselves, that appears to be responsible, according to the report.

The report said a high rate of oesophageal cancers occur in parts of Asia, South America, and East Africa, where regularly drinking very hot beverages is common.

The report was based on limited evidence from epidemiological studies that showed positive associations between cancer of the oesophagus and drinking very hot beverages, WHO said in a press release.

Studies in places such as China, Iran, Turkey and South America, where tea or mate is traditionally drunk very hot (at about 70 degrees Celsius), found that the risk of oesophageal cancer increased with the temperature at which the beverage was drunk, it said. "In experiments involving animals, there was also limited evidence for the carcinogenicity of very hot water."

"Smoking and alcohol drinking are major causes of oesophageal cancer, particularly in many high-income countries," said Dr Christopher Wild, director of the International Agency for Research on Cancer (IARC).

"However, the majority of oesophageal cancers occur in parts of Asia, South America, and East Africa, where regularly drinking very hot beverages is common and where the reasons for the high incidence of this cancer are not as well understood," he said.

Oesophageal cancer is the eighth most common cause of cancer worldwide and one of the main causes of cancer death, with approximately 400,000 deaths recorded in 2012, which accounts for 5 percent of all cancer deaths.

"The proportion of oesophageal cancer cases that may be linked to drinking very hot beverages is not known," said the press release.

Cold mate did not have carcinogenic effects in experiments on animals or in epidemiological studies, it said. "Therefore, drinking mate at temperatures that are not very hot was not classifiable as to its carcinogenicity to humans."

This was based on inadequate evidence in humans for the carcinogenicity of drinking cold or warm mate and inadequate evidence in experimental animals for the carcinogenicity of cold mate as a drinking liquid, it added.