Key Findings
A study published in the March 2026 issue of Chronic Obstructive Pulmonary Diseases: Journal of the COPD Foundation examined the association between isoflavone consumption and COPD symptoms in former smokers.
Participants with higher isoflavone intake reported fewer breathing-related symptoms, including reduced coughing and less difficulty clearing mucus, and improved lung health.
Isoflavones, commonly found in legumes and soy-based foods, were assessed via dietary questionnaires at baseline, three months, and six months.
Background
COPD, which includes emphysema and chronic bronchitis, is a progressive inflammatory lung disease affecting over 30 million Americans. It is the fourth leading cause of death globally. Diet and nutrition are recognized as modifiable risk factors for chronic lung disease.
Researcher Statement
"Further research is needed to identify specific nutritional components responsible for reducing symptoms of inflammatory conditions like COPD."
Daniel C. Belz, M.D., MPH, of the Division of Pulmonary and Critical Care Medicine at Johns Hopkins University and lead author, stated that larger studies are necessary to explore how increasing isoflavone consumption improves COPD symptoms and overall lung health.