Is coffee a class 1 carcinogen?

Is Coffee a Carcinogen? The Science Says No

For years, a lingering question has hovered around morning coffee rituals: could that comforting cup be putting your health at risk? The simple answer is no—coffee is not a class 1 carcinogen, and current scientific evidence backs that up.

Back in 1991, the International Agency for Research on Cancer (IARC), part of the World Health Organization, listed coffee as “possibly carcinogenic” due to limited evidence, particularly related to the bladder. But science evolves—and so has our understanding of coffee’s effects.

In 2016, after reviewing over 1,000 studies involving humans and animals, the IARC updated its classification. Coffee was moved to Group 3, meaning “not classifiable as to its carcinogenicity to humans.” In plain terms: there’s no consistent evidence linking coffee consumption to cancer. In fact, more recent research suggests that moderate coffee drinking may be associated with a reduced risk of certain conditions, including liver and endometrial cancers.

It’s worth noting that the temperature of the drink matters more than the coffee itself. Very hot beverages (above 65°C or 149°F), regardless of type, are classified as Group 2A—possibly carcinogenic—due to potential damage to the esophagus over time. So sipping your coffee while it’s still scalding might be the real risk, not the beans.

For most people, enjoying one or two cups a day isn’t just safe—it might even come with benefits. Coffee is rich in antioxidants and has been linked to improved cognitive function and a lower risk of type 2 diabetes and Parkinson’s disease.

Of course, individual sensitivities vary. If you’re prone to acid reflux or anxiety, or if caffeine disrupts your sleep, it’s wise to adjust your intake. But when it comes to cancer, the verdict is clear: your morning brew isn’t something to fear. The real carcinogen? Unfounded myths.