Fiber from cereal grains reduces cardiovascular disease risk.

Cardiovascular disease is the second leading cause of death worldwide. However, much of the risk associated with cardiovascular disease is modifiable via lifestyle, such as exercising, eating a healthy diet, and not smoking. Findings from a recent study suggest that eating foods rich in dietary fiber, especially the fiber present in cereal grains, reduces the risk of cardiovascular disease.

Dietary fiber is a broad term that refers to the non-digestible components of plant-based foods. It is generally characterized by its solubility in water, viscosity (i.e., ability to form thick gels), and fermentability. Cereal grains contain a mixture of insoluble fibers that bulk stool, viscous fibers that slow digestion, and fermentable fibers that feed the gut microbiota. Gut microbes break down cereal fiber, releasing micronutrients trapped in the fiber matrix and producing beneficial metabolic byproducts, such as short-chain fatty acids. Compared to fruit and vegetable fibers, cereal grain fibers tend to reduce the glycemic effect of meals and improve blood lipids, while supporting a healthy and diverse microbiota.

The investigation involved more than 4,100 participants (aged 65 years and older) enrolled in the Cardiovascular Health Study. Participants provided detailed information about their demographics, dietary intake, and medical history, including cardiovascular events. Because evidence indicates that cereal fibers reduce markers of inflammation, including C-reactive protein, the investigators measured various inflammatory markers, including CRP, IL-6, CD14, CD163, IL-2 receptor α, IL-1RA, IL-18, and TNF receptor 1, in the participants' blood.

The investigators found that higher cereal grain fiber intake markedly reduced cardiovascular disease risk and lowered the inflammatory markers CRP, IL-6, and IL-1RA. However, statistical analysis revealed that this decrease in inflammation had a modest effect on reducing cardiovascular risk, mediating just one-sixth of the association between cardiovascular disease and cereal grain fiber intake.

These findings suggest that eating foods rich in cereal grain fibers reduces the risk of cardiovascular disease and lowers inflammation. Additional studies are needed to tease out all the mechanisms that drive the protective effects of cereal fiber on cardiovascular health.

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