While the Dietary Guidelines for Americans recommends that most adults should aim to get 20–36 grams of fiber every day, we don’t often hear about which type of fiber is most helpful.
A new study published in JAMA Network Open found that certain kinds of dietary fiber may have a bigger effect on our health than others, especially for managing inflammation in our bodies.
Dietary Fiber and Inflammation
Research has shown that dietary fiber may help lower inflammation. That said, there are still many unanswered questions about fiber and inflammation.
For example, it’s not clear whether there is an association between fiber and inflammation in older adults. Researchers also don’t know if the source of fiber affects inflammation levels differently in generally healthy people.
To try to answer some of these questions, researchers from Columbia University looked at data from the Cardiovascular Health Study, an observational study that looks at risk factors for heart disease in adults aged 65 years or older. The researchers included 4,125 participants from the cohort in their study.
Each participant’s dietary intake was assessed using a food frequency questionnaire and their levels of inflammation were checked using blood samples that were collected at the start of the study.
The researchers looked at each person’s total fiber intake as well as the individual sources of fiber (cereal, vegetables, and fruit). Then, they analyzed the data to see if there was a potential association between dietary fiber intake and inflammation levels.
The results showed that total fiber was consistently associated with lower inflammation and lower cardiovascular disease incidence.
Specifically, cereal fiber—but not fruit or vegetable fiber—was linked to reduced inflammation. The researchers said that the findings suggest that cereal fiber might be more effective at lowering levels of systemic inflammation than other kinds of fiber.
Cereal fiber was also associated with a lower risk of cardiovascular disease. However, the researchers said that the link between cereal fiber with heart disease risk was more likely related to factors other than inflammation.
For example, it’s possible that some people who were eating more cereal fiber were replacing less healthy food choices with cereal grains.
Study Limitations
While the findings might be a boon for fiber fans, the research did have some important limitations.
Melissa Azzaro, RDN, LD, a registered dietitian and podcast host at Hormonally Yours, told Verywell that “while it is interesting that this study showed that cereal fiber was linked to a lower risk of inflammation and heart disease risk, the reasons were not clear.”
However, Azzaro also noted that “we do know from past studies that oat fiber, for example, has benefits on cardiovascular disease and cholesterol levels.”
Christine Byrne, MPH, RD, LDN, a non-diet private practice dietitian, told Verywell that inflammation-lowering potential is not the only reason fiber matters to your health.
“This study only measured the association between different types of fiber and inflammation, [but] there are many other benefits of fiber," Byrne said.
For example, Byrne highlighted the prebiotics in many fruits and vegetables, which can help promote a “healthier and more diverse gut microbiome.”
Beyond a Bowl of Cereal
Given the name, you might think that “cereal fiber” means having a bowl of your favorite cereal for breakfast. While that is one way you can get some fiber in your day, it’s not the only way.
From soluble beta-glucan to insoluble cellulose, grain and cereal fiber are found in a variety of foods, such as:
BranWhole-wheat breadOatsWhole-wheat pastaBrown riceCornSeedsBarleyOther whole grains
That said, if you look forward to having a bowl of Os or flakes in the morning, you don’t necessarily have to swap it for something else.
Azzaro said that “cereal can be part of a healthy diet,” but they recommend choosing low sugar, high fiber varieties, like oats and wheat bran.
To make a balanced meal, pair cereal with eggs and milk for protein and fruit for antioxidants and added fiber.
Azzaro also said that if you choose cereal, be “mindful of serving size” to avoid a blood sugar spike.
Don’t Focus On Just One Fiber
Since only about 5% of Americans get the recommended amount of fiber daily, focusing on one fiber over another may not be the priority.
If you’re not getting enough fiber, it will be beneficial to up your intake—whether you choose mostly cereal grains or other forms.
“It’s well established that all types of fiber—soluble and insoluble, and from all types of plant sources—have health benefits,” Byrne said.
While the new study may have suggested that cereal fibers are best at reducing inflammation, Byrne said “there’s no reason to start prioritizing grains over other fiber sources like fruits and vegetables.”
