Narrative review: high-fiber breakfast cereals and wheat bran support digestive and cardiometabolic health

Ready-to-eat breakfast cereals are a major source of dietary fiber, and their intake is associated with better diet quality and reduced incidence of chronic disease. However, dietary fiber intake remains significantly lower than recommended levels, particularly in North America. This fiber gap is one of the most important issues facing public health nutrition and deserves continued attention. This extensive analysis summarizes the body of research from the last decade on whole grain/high-fiber breakfast cereals, cereal fibers, and/or selected fiber sources commonly found in, or added to, breakfast cereals (e.g., wheat bran, psyllium). The primary health outcomes of interest for this review are digestive function, gut microbial effects, satiety signaling, body weight management, cardiovascular disease and blood glucose control. The evidence indicates that the fiber amount, fiber type, processing techniques, and numerous associated nutrients and phytochemicals in ready-to-eat breakfast cereals are all critical factors impacting health outcomes. Therefore, in addition to dietary guidance on total daily intake levels, guidance targeting specific health outcomes should also emphasize the unique mechanisms of action (e.g., gel-forming, digestion slowing, fecal-bulking, laxative, toxin binding, prebiotic) for the predominant types of fibers in ready-to-eat cereals and other fiber-rich foods. In particular, a growing body of research indicates that wheat bran, the predominant source of fiber in the U.S. and Canada, contains a novel array of fibers and phytonutrients that support bowel function and influence gut microbiota composition, and may help lower the risk for cardiometabolic disease. Notably, the research shows that individuals with low-cereal fiber consumption are most likely to benefit from an increase in their daily intake. While there is still much to discover regarding the mechanistic effects of different types of cereal fibers, continued encouragement to increase daily consumption of wheat fiber-rich foods, including ready-to-eat cereals, could help to close the fiber gap and reduce the incidence of multiple diet-related chronic diseases.