Does drinking a cup of coffee during chemotherapy adversely affect cancer treatment?

Based on current research on coffee and cancer treatment, the answer is no. 

According to Professor Lim Joo-han, who specializes in hematology-oncology at Inha University Hospital, the effect of coffee consumption on cancer patients, particularly those undergoing chemotherapy, is not fully understood. In a video on the Korean Society of Medical Oncology's YouTube channel (KSMO TV), Professor Lim explained that there is currently no clear consensus on the matter.

Despite numerous studies conducted on the potential effects of coffee on cancer treatment, Lim said it is challenging to draw a definitive conclusion with clear evidence about whether coffee is "bad" or "good" for cancer patients undergoing treatment.

"There are some studies that have reported some good effects rather than bad effects," Lim said. "There is evidence that it is not bad in the context of things like insulin sensitivity, but it is hard to say how much you should drink and whether it is really good." 

So, is it okay for cancer patients to drink coffee during chemotherapy? The answer, according to cancer treatment experts, is yes. 

"What we know for sure is that drinking coffee does not adversely affect the treatment outcome of cancer patients, so it is possible to drink coffee,” Lim said.