The International Agency for Research on Cancer (IARC), part of the World Health Organization, has published its review into the scientific evidence related to coffee and cancer, announcing that it has classified coffee in Group 3 for agents ‘not classifiable as to carcinogenicity to humans’. This means that the extensive scientific literature does not show an association between coffee consumption and cancer.
The review, published in Lancet Oncology, found no clear association between coffee intake and cancer at any body site and, in some cases, found evidence that coffee drinking may actually help reduce occurrence of certain cancers1, citing reduced risks for cancers of the liver and uterine endometrium.
Roel Vaessen, Secretary General of the Institute for Scientific Information on Coffee (ISIC), said: “ISIC welcomes and supports this announcement, which takes into account the large body of new scientific evidence published since IARC last evaluated coffee in 1991. In its latest review IARC judged that there is no negative relationship between coffee consumption and cancer. IARC concluded that coffee may actually be protective for some cancers, such as liver and endometrial cancer.”
He continued: “We also note IARC’s classification of very hot beverages consumed at very high temperatures over 65°C in Group 2A: “probably carcinogenic to the human oesophagus”. However, IARC did not find any conclusive evidence linking the consumption of coffee to oesophageal cancer.
“IARC’s findings suggest that temperature, rather than the type of drink, is linked to potential carcinogenicity. However, as any drink consumed at temperatures over 65°C is hot enough to scald the mouth and tongue, it is very unlikely that consumers would be able to drink their coffee at such very hot temperatures. Coffee is one of the most widely consumed beverages worldwide, drunk at an enjoyable temperature, which is typically below 60°C.”
It is important to note that this assessment relates to all beverages consumed at very high temperatures in general, not coffee in particular. In fact, very little of the research reviewed by IARC on this subject referred to coffee specifically.
IARC’s new classification concerning very hot beverage consumption concluded that very high temperature is defined as being significantly hotter than the temperature at which most people can comfortably drink coffee without scalding their mouth and tongue. Liquid temperatures higher than 65°C are above the normal human pain threshold.
ISIC noted that, overall, moderate consumption of coffee – typically 3-5 cups per day based on the European Food Safety Authority’s review of caffeine safety4 – has been associated with a range of desirable physiological effects in scientific literature and can fit within a healthy, balanced diet and active lifestyle.