Association of dietary antioxidants and waist circumference with pulmonaryfunction and airway obstruction

Dietary antioxidants, waist circumference, and pulmonary function were meas ured in the Fourth Scottish MONICA cross-sectional survey of 865 men and 97 1 women aged 25-54 years. Waist circumference was inversely related to forc ed expiratory volume in the first second (FEV1) and forced vital capacity ( FVC), even after adjustment for age, height, weight, working status, energy intake, and smoking variables in a multiple linear regression model (men: beta = -0.017 for FEV1 I/cm, p < 0.01 and <beta> = -0.008 for FVC, p = 0.04 ; women: beta = -0.009 for FEV1, p < 0.01 and <beta> = -0.007 for FVC, p = 0.01). After additional adjustment for waist circumference, estimated vitam in C and beta -carotene intakes were positively associated with lung functi on in men (vitamin C: beta = 0.102 for FEV1 I/mg/day, p = 0.03; beta -carot ene: beta = 0.073 for FVC I/mug/day, p = 0.02). Retinol and vitamin E were not significantly related to lung function for either sex. A case-control s tudy of airway obstruction showed that waist circumference was significantl y associated, while vitamin C could be protective. The study suggests that adequate intake of antioxidants and avoidance of increasing girth could hel p to preserve lung function.