A high fiber diet is known to protect against heart disease and diabetes, and now there’s evidence that lung disease could be added to the list as well.

More than 11 million people in the U.S. have lung disease, primarily chronic obstructive pulmonary disease (COPD), which is the third leading cause of death.

Researchers from the University of Nebraska Medical Center reviewed records of 1,921 adults, ages 40 to 79, who participated in a large national database compiled by the Centers for Disease Control, which is unique because it combines interviews with physical examinations.

They found that those people who ate the most fiber tested better in lung capacity tests. Specifically, 68.3 percent of the fiber eaters had normal lung function compared to 50.1 percent and 14.8 percent had airway restriction, compared to 29.8 percent in the bottom quartile.   Those with the highest fiber intake also had greater lung capacity and could exhale more air in one second, which are also important indicators.

Health experts have long sought ways that people can improve their lung health, in addition to quitting smoking, so they are hoping that upping fiber intake could provide such an opportunity, the researchers say of their findings, which appear online in Annals of the American Thoracic Society.