If a child eats three or more burgers a week they are at risk of developing asthma and wheeze, according to an international study. Conversely, a Mediterranean diet, featuring fruit, vegetables and fish, does the opposite and dilutes the risk. The research was collected between 1995 and 2005 on 50,000 children who were between the ages of 8 and 12. The study also revealed that there was no correlation between diet and developing common allergies, such as grass and tree pollen. Burger consumption was found to be linked with a higher lifetime prevalence of asthma and wheeze, especially among children in rich countries.