But now a new study has shown a direct link between eating fish, fruit and dairy products and improved lung function among patients with chronic obstructive pulmonary disease (COPD). Conducted by researchers in the U.S. and Europe, the study specifically looked at COPD patients' lung function within 24 hours of eating grapefruit, bananas, fish and cheese.
The study will be presented at the ATS 2014 International Conference. "Diet is a potentially modifiable risk factor in the development and progression of many diseases, and there is evidence that diet plays a role in both the development and clinical features of COPD," said study lead author Corinne Hanson, Ph.D. "This study aimed to evaluate that association."
For their study, the researchers used data from the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints study (ECLIPSE). ECLIPSE was designed to help determine how COPD progresses and to identify biomarkers associated with the disease. Limited diet records were available for 2,167 ECLIPSE participants who provided dietary intake information at eight time points over a three-year period. Each participant reported the amount of a specific food they had consumed during the previous 24 hours.Next, the researchers looked at specific standard lung function measurements for the same group of people, including the six-minute walk test (SMWT), St. George's Respiratory Questionnaire (SGRQ) scores and inflammatory biomarkers.
Results were adjusted for age, sex, body mass index (BMI) and smoking.What they found was that people who reported recently consuming fish, grapefruit, bananas or cheese had showed improvement in lung function, less emphysema, improved six-minute walk scores, improved SGRQ scores, and a decrease in certain inflammatory markers associated with poor lung function including white blood cells and C-reactive protein. "This study demonstrates the nearly immediate effects a healthy diet can have on lung function in in a large and well-characterized population of COPD patients," Hanson said.
"It also demonstrates the potential need for dietary and nutritional counseling in patients who have COPD." Based on these results and the results of other studies indicating a link between COPD and diet, the role of diet as a possible modifiable risk factor in COPD warrants continued investigation, she added.