Does Coffee Cause Cancer?

It feels like no matter what topic you pick these days, there’s “new research” that says it causes cancer, and there’s research that says it will help you live forever. Coffee is no exception to this, with articles and studies going both ways.

According to the International Agency for Research on Cancer (IARC), an agency for the World Health Organization (WHO), coffee is no longer classified as a carcinogen as of June 15, 2016. It was previously classified as a possible carcinogen back in a study from 1991. You can find the press release here.

A study released September 17, 2015 by the American Heart Association (AHA) observing over 200,000 people over a 30 year period concludes that coffee consumption (including caffeinated and decaffeinated) lowers risk of all-cause mortality, however, no affect on cancer-related mortality was observed. This effect was stronger as the number of cups per day increased – up to 5 cups per day.

So, the answer also to does decaf coffee cause cancer is no. The study doesn’t go into details about whether the coffee is decaffeinated by CO2, Swiss Water or other methods. However, it doesn’t decrease your risk either.


With the SCAA (Specialty Coffee Association of America) and CAC (Coffee Association of Canada) both reporting about 3.2 cups/day for the average coffee drinker, coffee could play a significant factor in keeping the overall population healthy. Approximately 34% of Americans and 65% of Canadians drink at least one cup per day.

Does Smoke from Roasting Coffee Cause Cancer?

Any sort of burnt particulate being inhaled has the potential to cause cancer, but no research has come to the firm conclusion that smoke from roasting coffee will cause cancer. There is evidence that roasting coffee releases chemicals known as Diacetyl and 2,3-pentanedione, which are linked to obliterative bronchitis – an irreversible scarring of the lung tissue.

These two compounds were previously known to be linked to the flavoring agents used in flavored coffee (as well as butter flavoring in popcorn facilities) that become airborne during the mixing and grinding process in coffee roasting facilities.