Asthma and obesity in children are common chronic conditions and both disorders have been increasing in the last 2 to 3 decades. The changes of dietary habits and a sedentary life style could have played a role in increasing the prevalence of both conditions. The aim of this report is to analyse the relation between some respiratory conditions (current wheezing, asthma and chronic cough) with dietary habits, body mass index (BMI), the physical activity and the habit to watch television. A total of 19,995 children (10,294 males and 9701 females) were investigated. Current wheezing is associated with increased BMI (V quintile OR=1.65), TV watching (more than 5 h/day OR=1.53), adding salt to the foods (OR=2.45), and fizzy drink (5 times or more per week OR=1.31). Children who often eat tomatoes, fruits, cooked vegetables and citrus fruits have a lower risk of current wheeze. The pattern of association is similar for asthma. High BMI, TV watching, adding salt to foods, and fizzy drink are risk factors for chronic cough. An increased BMI and TV watching are strongly related to respiratory symptoms. Our data confirm that dietary factors such as salt, vegetables and fruits are associated with the prevalence of respiratory symptoms in children.