Background: Results of epidemiological studies relating individual dietary factors to chronic obstructive pulmonary disease (COPD) are inconsistent. To evaluate the cross sectional association of dietary factors with pulmonary function, data were collected from middle aged men in three European countries.
Methods: The data were collected in the 1960s in Finland (n = 1248), Italy (n = 1386), and the Netherlands (n = 691). Dietary intake was estimated using the cross-check dietary history method. Forced expiratory volume (FEV(0.75) or FEV(1), here called FEV) was measured by spirometry. Associations were adjusted for age, height, smoking, body mass index (BMI), alcohol consumption, and energy intake.
Results: FEV was positively associated with intake of vitamin E in Finland, with intake of fruit in Italy, and with intake of beta-carotene in the Netherlands. In all three countries men with intakes of both fruit and vegetables above the median had a higher FEV than those with a low intake of both foods. The difference in FEV ranged from 110 to 169 ml before and from 53 to 118 ml after energy adjustment. Differences in FEV for intake of three antioxidants (vitamins C and E and beta-carotene) above versus below the median ranged from 61 to 181 ml before and from -35 to 58 ml after energy adjustment. Intake of fish was not associated with FEV.
Conclusions: In three European countries a high intake of fruit and vegetables was positively associated with pulmonary function. A high intake of all three antioxidants tended to be positively associated with pulmonary function before, but not after, adjustment for energy intake. Associations of individual antioxidants with pulmonary function were not consistent across countries.