Patients who drink four or more cups a day are 42 per cent less likely to see their cancer return, and are 33 per cent less likely to die from cancer, compared to people who never drink coffee. Those who drank three or fewer cups a day had some protection, but nowhere near as great, while drinking just one cup a day didn't make any difference.
Researchers from the Dana-Farber Cancer Institute reckon coffee's caffeine is solely responsible for the protective effect. They're not sure of the mechanism, but think it may be because caffeine increases the body's sensitivity to insulin, so less is produced, and this may also reduce inflammation in the body. It's already been shown that coffee reduces the risk of type 2 diabetes.
The finding is based on a survey of nearly 1,000 stage III colon cancer patients who had been treated with surgery or chemotherapy.
(Source: Journal of Clinical Oncology, 2015; doi: 10.1200/JCO.2015.61.5062)