New research disproves recent findings that suggested soy could play a role in reducing the severity of the disease.
The study, from Northwestern Medical medicine and the American Lung Association Asthma Clinical Research Network, published Tuesday in the Journal of the American Medical Association (JAMA), examined the effects of soy on 386 adults and children with poorly controlled asthma over a six-month period.
The randomised double blind study found that soy supplements did not improve lung function and highlights the importance of focusing on overall health as a way of managing the condition.
"You are what you eat, but that's a whole constellation of foods, not just a single food or a single component of a food," said first author Dr Lewis Smith, professor of medicine at Northwestern University Feinberg School of Medicine. "Instead of focusing on supplements, we should be taking a more holistic approach."