Diet and chronic obstructive pulmonary disease: independent beneficial effects of fruits, whole grains, and alcohol (the MORGEN study)

Background In recent years antioxidants, foods rich in antioxidants (e.g. f ruits, vegetables) and fish have been suggested to protect against chronic obstructive pulmonary disease (COPD). There are also indications for a prot ective effect of whole grain intake and of consuming moderate amounts of al cohol. It is, however, not clear whether the effects of the different dieta ry factors on COPD are independent of each other and if so, whether their e ffects are additive. Objective To gain more insight into the potential protective effect of diet on CORD, we studied fruit, vegetable, fish, alcohol and whole grain consum ption simultaneously in relation to pulmonary function and COPD symptoms. Methods Analysed were cross-sectional data collected in 13 651 men and wome n aged 20-59 years participating between 1994 and 1997 in the MORGEN study (monitoring project on risk factors and health in The Netherlands). Regress ion models were adjusted for age, gender, height (for pulmonary function on ly), smoking, BMI and energy intake. Results Fruit and whole grain intake showed independent beneficial associat ions with COPD (P-trend < 0.001). Furthermore, in subjects with low alcohol consumption (1-30 g/day) the forced expiratory volume in 1 s (FEV1) was hi gher and the prevalence of CORD symptoms lower than in non-drinkers (P < 0. 001). The effects of a favourable intake of fruits (> 180 g/day), whole gra ins (> 45 g/day) smd alcohol (1-30 g/day) were largely additive. In the 299 8 subjects with a favourable intake of the three foods, the FEV1 was 139 mL higher and the prevalence of COPD symptoms lower (odds ratio (OR) = 0.44) than in subjects (n = 1406) with unfavourable intakes of fruits, whole grai ns and alcohol (P < 0.001). A similar effect was observed in those who had never smoked. Fish and vegetable intake did not show independent beneficial associations with CORD. Conclusions Our results suggest independent beneficial effects of fruits, w hole grains and alcohol on CORD that are largely additive and cannot be exp lained by smoking habits.