Bread made from whole grains, canned beans, breakfast cereals, and yogurt may reduce the risk of colorectal cancer, despite being considered processed foods. This conclusion was reached by researchers at the U.S. National Cancer Institute after studying data from more than 461,000 people. The results were published in the journal PLOS Medicine.
The researchers followed participants for 18 years, during which 10,075 cases of colorectal cancer were diagnosed. Overall, people who consumed more processed foods did not show a significant increase in risk. However, results varied depending on the type of food.
Each additional daily serving of whole grain bread was associated with a 13% reduction in the risk of colorectal cancer. A stronger association was seen with fiber: each additional 10 grams per day of processed foods such as canned beans was linked to a 28% reduction in risk. Additional servings of certain dairy products, including sweetened yogurts and cottage cheese, were associated with a 25% reduced risk.
However, meat showed the opposite association. Each additional daily serving of processed meat, such as bacon, was linked to an 8% increase in risk. The researchers noted that consumption of unprocessed meat showed a 4% increase.
The authors suggest that some processed foods may be beneficial due to their content of fiber and other nutrients. Fiber supports normal bowel function and is associated with a lower risk of colorectal cancer.
The researchers emphasize that these results do not prove causality. The study included Americans aged 50 to 71, so the findings cannot be automatically generalized to younger people or the general population.
