Daily coffee could protect from colorectal cancer
In a study published in the April issue of Cancer Epidemiology, Biomarkers & Prevention, having regular coffee consumption is inversely correlated to colorectal cancer risk according to researchers from the Comprehensive Cancer Centre of Keck Medicine at the University of Southern California. The study, available in the online issue of Cancer Epidemiology, Biomarkers & Prevention, states that 2.5 servings of coffee daily decreased the risk by up to 50 percent.The more coffee consumed, the lower the risk, says senior author Stephen Gruber. The reduced risk was observed in all types of coffee. That goes for all kinds of the caffeinated and even decaffeinated ones. For their study, Dr. Gruber and colleagues analysed the data of 5,145 individuals who had been diagnosed with colorectal cancer, alongside 4,097 people who did not have the disease.All participants were part of the Molecular Epidemiology of Colorectal Cancer study, which is a population-based, case-control study conducted in northern Israel.As part of the study, subjects were required to complete a food frequency questionnaire, detailing their daily intake of espresso, instant, decaffeinated and filter coffee, as well as their daily consumption of other beverages.
The participants also completed a questionnaire that disclosed information on family history of cancer, diet, physical activity levels, smoking habits and other factors that may affect their risk of colorectal cancer.The researchers found that drinking one to two servings of coffee a day – defined as moderate coffee consumption reduced the risk of colorectal cancer by 26%, compared with participants who drank less coffee.Not only did these findings remain after accounting for known colorectal cancer risk factors, but the researchers also found that the reduced risk was seen across all coffee types even decaffeinated.”We were somewhat surprised to see that caffeine did not seem to matter,” says Dr. Gruber. “This indicates that caffeine alone is not responsible for coffee’s protective properties.”The researchers speculate that coffee has many components that explain this benefit and believes is a protective agent against colorectal cancer because several of its components affect the physiology of the colon.
These compounds include caffeine, melanoidins, diterpenes, and polyphenols. Protection may arise from changes to the microbiome, antioxidant effects, antimutagenic effects, reduction of bile acid secretion, and improved bowel functions such as motility and capacity. They cite that polyphenol and caffeine act as antioxidants that probably prevent the growth of colon cancer cells.The roasting process can also generate melanoidins, which could encourage colon mobility. Additionally, coffee’s diterpenes may also boost the defence against oxidative damage, preventing cancer.“The levels of beneficial compounds per serving of coffee vary depending on the bean, roast, and brewing method,” says first author Stephanie Schmit. “The good news is that our data presents a decreased risk of colorectal cancer regardless of what flavour or form of coffee you prefer.”“While the evidence certainly suggests this to be the case, we need additional research before advocating for coffee consumption as a preventive measure,” Gruber adds. “That being said, there are few health risks to coffee consumption, I would encourage coffee lovers to revel in the strong possibility that their daily mug may lower their risk of colorectal cancer.”