FRIDAY, Aug. 21, 2026 (HealthDay News) -- Higher diet quality is associated with better lung function (LF), especially among individuals with asthma or chronic obstructive pulmonary disease (COPD), according to a study published online Aug. 17 in ERJ Open Research.Arturo F. Martinez-Rodriguez, from the University of Groningen in the Netherlands, and colleagues examined whether diet and LF differ according to asthma or COPD status among adults in the Lifelines cohort study. The Lifelines diet score (LLDS) was used to calculate dietary quality. At baseline and two follow-ups (around 10 years), LF was assessed via pre-bronchodilator spirometry (forced expiratory volume in one second [FEV1], forced vital capacity [FVC], and FEV1/FVC).The researchers observed an association for higher LLDS with higher LF and slower decline. In cross-sectional analyses including 83,460 individuals, higher LLDS was associated with higher FEV1 and FEV1/FVC levels among those with asthma and COPD compared with those without asthma or COPD. In longitudinal analyses including 37,752 participants, higher LLDS was associated with slower FEV1 decline, FVC, and FEV1/FVC in patients with COPD compared with those without COPD."These findings support the potential role of diet as a modifiable lifestyle factor in respiratory health, especially in participants with COPD," the authors write.Abstract/Full Text.Sign up for our weekly HealthDay newsletter