Adherence to the Mediterranean diet and fresh fruit intake are associated with improved asthma control

Abstract

Background: The traditional Mediterranean diet is claimed to possess antioxidant and immune-regulatory properties in several chronic diseases. Typical Mediterranean foods have recently been associated with improvement of symptoms of asthma and rhinitis in children. However the effect of adherence to Mediterranean diet on adult asthma outcomes is unknown. We aimed to investigate the association between adherence to Mediterranean diet and asthma control. Methods: Cross sectional study of 174 asthmatics, mean (SD) age of 40 (15) years. The patients were defined as controlled, in contrast to noncontrolled, if they showed FEV1 >= 80% of predicted, exhaled nitric oxide (NO) <= 35 ppb, and Asthma Control Questionnaire score < 1. Dietary intake was obtained by a food frequency questionnaire, and Mediterranean diet was assessed by alternate Mediterranean Diet (aMED) Score. Logistic regression models adjusting for confounders were performed to estimate the association between Mediterranean diet and asthma control. Results: Controlled asthmatics (23%) had significantly higher aMED Score, intake of fresh fruit, and lower intake of ethanol compared to noncontrolled (77%). High adherence to Mediterranean diet reduced 78% the risk of noncontrolled asthma after adjusting for gender, age, education, inhaled corticosteroids and energy intake (OR = 0.22; 95% CI = 0.05-0.85; P-trend = 0.028). The higher intake of fresh fruit decreased the probability of having noncontrolled asthma (OR = 0.29; 95% CI = 0.10-0.83; P-trend = 0.015), while the higher intake of ethanol had the opposite effect (OR = 3.16; 95% CI = 1.10-9.11; P-trend = 0.035). Conclusion: High adherence to traditional Mediterranean diet increased the likelihood of asthma to be under control in adults. The study introduces a novel link between diet and asthma control, as measured by symptoms, lung function and exhaled NO.