This review focuses on the role of dietary factors in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD). Reduced pulmonary function and indicators of airway obstruction have been shown to be strong indicators for mortality ; therefore, a link with diet in the pathogenesis of these diseases would have important public health implications.
Both asthma and COPD involve inflammation of the airways. Asthma is a chronic inflammatory disorder involving many different cells and cell membranes. It is characterized by reversible airway constriction. It is the most common chronic disease in children, and its prevalence is rising . COPD refers to a collection of conditions, including emphysema and chronic bronchitis, which can affect various structures in the lung. It is characterized by the presence of airflow obstruction and a slow progressive decline in forced expiratory volume in 1 second (FEV1) . COPD is a leading cause of worldwide morbidity and mortality. By 2020, it is expected to become the fifth cause of combined worldwide mortality and disability .
Several dietary factors have been implicated in the pathogenesis of asthma and COPD, mainly because of their potential role in inflammatory reactions, the activities of airway smooth muscle, and enzymatic reactions that affect neuromuscular transmission .