Teens and kids who eat a lot of fast food may be at greater risk for developing asthma, eczema and allergies, according to a new study published in the British Medical Journal's respiratory magazine, Thorax.

For the study, researchers from the University of Auckland in New Zealand and the University of Nottingham in the United Kingdom looked at surveys from more than 500,000 kids in 51 countries to determine how diet affected their allergy-related risks. They found that eating fast food three times a week may lead to asthma, eczema and itchy, watery eyes in children.

Researchers surveyed kids and their parents to determine whether or not they experienced symptoms of allergies, asthma and eczema. Participants also shared what types of foods they consumed each week. In the study, children in their early teens who ate fast food three or more times each week had a 39 percent greater risk of severe asthma. For 6- and 7-year-olds, there was a 27 percent increased risk. Overall, kids who ate fast food three or more times a week had about a 30 percent increased risk of severe allergies. The results were consistent across all age groups regardless of gender or socioeconomic status.

Interestingly, kids who ate fruit were able to cut their risk of developing these conditions. Researchers found that kids who ate three or more portions of fruit each week reduced their risk of severe asthma, eczema and allergies by between 11 and 14 percent.

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Fast food linked to higher asthma and allergy risk
New study links fast-food consumption to a greater risk for developing asthma, eczema and allergies.