Bowel cancer claims the lives of 5,354 Australians every year. Risk factors include older age, family history of the disease, and eating lots of red meat – especially processed meats like salami and bacon.
Plant-based diets or plant-forward eating patterns focus on foods primarily from plants.
So how do people on plant-based diets measure up when it comes to their risk of developing bowel cancer?
In a recent study, researchers looked at more than 170,000 people in a US population cohort aiming to help answer questions about the development of disease. When they entered the cohort, people were quizzed on their typical diet and this was used to sort them into different groups based on how much of their diet was plant-based. This data was linked with the incidence of cancer in each group based on state surveillance of cancer cases and registry information.
High rates of plant food consumption were strongly inversely linked to risk of colorectal cancer – but only in men. That meant that for men who scored in the fifth and highest quintile of plant-based food consumption, there was a 24% lower risk of bowel cancer relative to those in the lowest quintile. Interestingly, the same pattern was not found for women – a plant-based diet was not significantly associated with bowel cancer risk.
It’s not clear why women were different in this study, though the authors speculated that it’s because women typically eat a higher proportion of plant-based foods overall, there may not be as much benefit beyond a certain ‘dose’ of such foods. It’s also known that men are at higher risk of bowel cancer, and the reduction in risk may be more significant for them.