IARC's declassification of coffee 'does not happen often,' ISIC secretary general says

IARC, a subsidiary of the World Health Organization, aims to promote international collaboration in cancer research as a scientific entity, not a regulatory body, the organization said.

Supporting the finding was the Institute for Scientific Information on Coffee (ISIC), a not-for-profit organization focussed on the study and disclosure of science related to coffee and health. 

“IARC’s decision is supported by numerous studies and meta-analyses, which have shown no significant association between coffee consumption and total cancer mortality,” ​Roel Vaessen, secretary general of ISIC, told BeverageDaily.

“Their assessment identifies the strength of the scientific evidence. It’s up to organizations like the EFSA to take that, and then come to an overall health risk evaluation.”​

IARC reclassifies coffee​

IARC classifies substances on a scale ranging from Groups 1 through 4, with Group 1 meaning a substance is “carcinogenic to humans.”​  In this instance, coffee was declassified from Group 2B (“Possibly carcinogenic to humans”) to Group 3 (Not classifiable as to its carcinogenicity to humans).​

The review also discovered that, in some cases, drinking coffee may actually help reduce occurrence of certain cancers including liver and endometrial cancer.

“Coffee used to be in the 2B category which means possibly carcinogenic to the human being and has been reduced to category 3 or non-classifiable,”​ Vaessen said. “And that doesn’t happen often.”​

It is important to note that IARC’s classification system does not reflect a judgement or measure of the likely risk to public health in everyday life. To date, IARC has only classified one substance in Group 4.

Desirable effects from coffee consumption​

Overall, ISIC feels that the body of science indicates that moderate consumption of coffee – typically three to five cups per day based on the European Food Safety Authority’s review on caffeine safety – has been associated with a range of desirable physiological effects in the scientific literature.

“Coffee drinkers can be even more reassured that drinking coffee in moderation doesn’t pose any risk,” ​Vaessen said.

IARC says beware of very hot beverages ​

IARC has published a separate review into the scientific evidence related to very hot beverages and cancer, classifying drinks consumed at very high temperatures (above 65°C) in Group 2A: “probably carcinogenic to the human esophagus.”​ This new classification concerns very hot beverage consumption hotter than the temperature at which most people can comfortably drink a beverage without scalding their mouth and tongue.

IARC’s review looked at all beverages drunk at very hot temperatures, including mate and tea. Very little of the research examined by IARC looked at coffee specifically and since coffee is typically enjoyed at a temperature below 65°C, insufficient evidence of an association was found.