I have been told that should stay away from fast food like burgers and fries. Is this really true? Cause I like burgers and fries. Good question. And the answer is…maybe. One study found that asthma patients who ate foods high in fat had more trouble breathing than patients who ate a low fat meal. To be clear, the study doesn’t prove that burgers and fries, specifically, cause or worsen asthma. But it does suggest that high fat foods, like a lot of junk food, may be bad for asthma. Other studies have found that foods high in fat and salt trigger the immune system, which can lead to swelling in the body, including the airway. And when your airway is swollen, it’s harder to breath.