There are many evidences of the protective effects of a high fiber diet in certain disease states; however, little is known about its relationship to lung health. A research conducted by a team of researchers from Nebraska, Kentuccky and New Zealand universities focuses on this particular matters, by refererring to the National Health and Nutrition Examination Surveys (NHANES), which contains spirometry measures and dietary intake information, hence allowing the researchers to assess this relationship. In order to determine the association between fiber intake and measures of lung function in a representative sample of U.S. adults, the study included 1,921 partecipants who had spirometry measurements and fiber intake available. The primary outcomes were lung function measurements, including FEV1, FVC, and percent predicted FEV1 and FVC. Researchers also conducted a categorical analysis of fiber intake and airflow restriction and obstruction based on GOLD and Spirometry Grade (SG) classifications. Multivariable regression models were used to look at the association of lung function measurements with dietary fiber intake after adjustment for relevant confounders. All analyses accounted for the weighted data and complex design of the NHANES sample. Subjects in the highest quartile intake of fiber had mean FEV1 and FVC measurements that were 82 mL and 129 mL higher that the lowest quartile of intake (p=0.05 and 0.01, respectively), and mean percent predicted FEV1 and FVC values that were 2.4 and 2.8 percentage points higher (p=0.07 and 0.02, respectively). In the categorical analysis, higher fiber intake was associated with a higher percentage of those with normal lung function (p=0.001) and a significant decline in the proportion of participants with airflow restriction (p=0.001). As a conclusion, low fiber intake was associated with reduced measures of lung function. A diet rich in fiber-containing foods may play a role in improving lung health.