Dietary Fiber and Colorectal Cancer Risk
Dietary Fiber and Colorectal Cancer Risk
A systematic review and meta-analysis by Arayici and colleagues, published in Nutrition and Cancer in 2022, examined the association between soluble and insoluble dietary fiber intake and colorectal cancer risk. The study focused on adults at average risk for colorectal cancer, pooling data from observational studies and cohort analyses to determine whether higher fiber consumption is linked to reduced incidence of this common cancer.
The interventions assessed were dietary intake of soluble fiber (found in foods like oats, legumes, and some fruits) and insoluble fiber (from whole grains, vegetables, and nuts). Comparisons were made between individuals with the highest versus lowest levels of fiber consumption, with outcomes focused on the development of colorectal cancer.
The meta-analysis found that higher intake of both soluble and insoluble fiber was associated with a lower risk of colorectal cancer. Specifically, individuals in the highest intake groups had a statistically significant reduction in risk compared to those in the lowest intake groups. The protective effect was observed across multiple study populations and geographic regions, highlighting the consistency of the relationship. Mechanistically, fiber may help reduce cancer risk by improving bowel transit time, promoting healthy gut microbiota, and producing beneficial metabolites like short-chain fatty acids.
For patients and the general population, these findings reinforce the importance of a fiber-rich diet in colorectal cancer prevention. Incorporating a variety of fiber sources, including vegetables, whole grains, legumes, and fruits, may support gut health and reduce cancer risk, complementing other lifestyle and medical strategies for colorectal cancer prevention.
Reference:
Arayici ME, Mert-Ozupek N, Yalcin F, Basbinar Y, Ellidokuz H. Soluble and Insoluble Dietary Fiber Consumption and Colorectal Cancer Risk: A Systematic Review and Meta-Analysis. Nutr Cancer. 2022;74(7):2412-2425. doi: 10.1080/01635581.2021.2008990. Epub 2021 Dec 2. PMID: 34854791.
