If increased risk of obesity and diabetes doesn’t give your family enough reason to chuck fast food, here’s another consequence to add to the list: Those french fries and chicken nuggets may exacerbate kids’ asthma and eczema. In a recent study involving more than 500,000 children ages 6 to 14, New Zealand scientists found when kids ate greasy fast food three or more times per week, they were significantly more likely to report symptoms of asthma, eczema, and congestion.

Researchers think fast food’s copious trans and saturated fats dampen developing immune systems, making little bodies unable to fend off immunity-based conditions such as asthma. On the flip side, results from the same study suggest that regularly eating fruit decreases the likelihood of asthma and eczema.