A diet high in fiber may not only protect against diabetes and heart disease, it may also reduce the risk of developing lung disease, according to recent research. The study, “The Relationship between Dietary Fiber Intake and Lung Function in NHANES,” was published in the Annals of the American Thoracic Society.

Extensive research supports the protective effect of a high-fiber diet in certain medical conditions, but little is known about its relationship to lung health.

Researchers have now analyzed data from 1,921 adults retrieved from the National Health and Nutrition Examination Surveys (NHANES). The team collected lung function measurements, data on fiber intake, airflow restriction, and obstruction based on GOLD and Spirometry Grade (SG) classifications.

Fiber intake was considered based on the participants’ consumption of fruits, vegetables, legumes and whole grains. Participants who recalled eating diets with more than 17.5 grams of fiber a day were in the top fiber group (571 people). Participants who ate less than 10.75 grams of fiber a day were in the lower group (360 individuals).

The results revealed that:

• 68.3 percent of the adults in the group with the highest intake of fiber had normal lung function, compared to 50.1 percent in the lowest group.
• 14.8 percent had airway restriction in the highest-fiber group, compared to 29.8 percent in the lowest-fiber group.

In two breathing evaluations, adults with the highest fiber intake performed significantly better than those with the lowest intake. Those in the top fiber-intake group had a greater lung capacity and could exhale more air in one second than those in the lowest fiber-intake group.

The results indicated that a low dietary fiber intake was associated with reduced measures of lung function, and an increased prevalence of participants with airway restriction. Based on the findings, the researchers suggested that a diet rich in fiber-containing foods may play a role in improving lung health.

“Lung disease is an important public health problem, so it’s important to identify modifiable risk factors for prevention,” the study’s lead author, Dr. Corrine Hanson, an associate professor of medical nutrition at the University of Nebraska Medical Center, said in a news release. “However, beyond smoking, very few preventative strategies have been identified. Increasing fiber intake may be a practical and effective way for people to have an impact on their risk of lung disease.”