Researchers at Columbia University’s Mailman School of Public Health and colleagues evaluated whether dietary fiber intake was associated with decreased inflammation in older adults and whether fiber was inversely related to cardiovascular disease. The results showed that total fiber, and more specifically fiber from cereals, but not fiber from fruits or vegetables, was consistently associated with lower inflammation and a lower incidence of CVD. Until now, there was limited data on the link between fiber and inflammation among older adults, who have higher levels of inflammation compared to younger adults. The study findings are published in Open JAMA Network.
The research includes data from a large, well-characterized prospective cohort of older people, with detailed data on dietary intake, inflammation, and CVD incidence. The research confirmed previously observed associations between dietary fiber and CVD and extended those investigations to include the source of the fiber, the relationship of fiber to multiple inflammatory markers, and to test whether inflammation mediated the relationship between dietary fiber and CVD. CVD.
Of 4125 adults enrolled in the Cardiovascular Health Study from 1989 to 1990, participants received a food frequency questionnaire that was administered to those without prevalent CVD at enrollment and were then followed by CVD development visits ( stroke, myocardial infarction, and atherosclerotic cardiovascular death) through June 2015. Blood samples were evaluated for markers of inflammation.
“Higher dietary fiber intake is associated with lower CVD risk. A common hypothesis has been that higher fiber intake reduces inflammation, which subsequently leads to lower CVD risk,” said Rupak Shivakoti, PhD, professor epidemiology assistant at Columbia Mailman School. “With the findings of this study, we are now learning that a particular type of dietary fiber, fiber from cereals, but not fiber from fruits or vegetables, was associated with lower inflammation. With the findings of this study, we are now learning that cereal fiber has the potential to reduce inflammation and should be tested in future intervention studies.”
Although there is data to suggest that fiber in general may have anti-inflammatory effects by improving bowel function, modifying diet and satiety (eg, reducing fat and total energy intake), and improving lipid profile metabolism and glucose, why cereal fiber and not vegetable fiber? Whether the fiber in the fruit is associated with less inflammation is unclear and warrants further investigation, Shivakoti noted. In addition, she notes that it’s not clear whether cereal fiber per se or other nutrients in cereal fiber-rich foods are driving the observed relationships.
“Furthermore, we learned that inflammation had only a modest role in mediating the observed inverse association between cereal fiber and CVD,” Shivakoti observed. “This suggests that factors other than inflammation may play a larger role in reducing cereal fiber-associated CVD and will need to be evaluated in future population-specific interventions.
Coauthors are from Columbia University’s Mailman School of Public Health; University of Washington; Brigham and Women’s Hospital; Harvard Medical School; Boston Veterans Health Care; University of Vermont Larner School of Medicine; San Francisco Veterans Affairs Health Care System; University of California-San Francisco; Kaiser Permanente Washington Institute for Health Research; New York Academy of Medicine; Beth Israel Deaconess Medical Center; and the Harvard Chan School of Public Health,
The research was supported by the National Heart, Lung, and Blood Institute, the National Institute of Neurological Disorders and Stroke, and the Eunice Kennedy Shriver National Institute of Child Health and Human Development.
Materials provided by Columbia University Mailman School of Public Health. Note: content can be edited for style and length.