For many asthma sufferers who aren’t able to control their symptoms with medication, the key may be to eat more soybeans.
The St Louis Post Dispatch is reporting that the Washington University School of Medicine is one of 19 institutions across the country conducting a clinical trial to test the effect of soy compounds on the respiratory disease.
“The number of people in the United States who have asthma has increased in recent years,” said Dr. Mario Castro, lung specialist at Barnes-Jewish Hospital and lead investigator for the St. Louis study. “One reason for the increase could be dietary changes that decrease consumption of foods, such as soy, that are rich in antioxidants.”
In 2007, the Centers for Disease Control and Prevention reported 34 million people had been diagnosed with asthma. That equated to about 13.1 percent of children under the age of 18, and 10.9 percent of adults. The disease also took the lives of almost 3,500 people that year and cost the country $30 billion in treatment costs.
Scientists are looking to soybeans as a possible treatment because they contain powerful antioxidants called isoflavones. Pilot studies have found that isoflavones can reduce the production of inflammatory compounds produced by white blood cells. Airway inflammation is an important cause of asthma symptoms.
Castro also helped conduct a survey 10 years ago that found those who consumed the least amount of soy had the most flare-ups of their asthma.
Alternative treatments are needed because many patients aren’t able to control the disease with available medications, Castro said.
“We see a need for a different approach, and if soy proves to be beneficial for asthma, a simple modification in diet could be a workable and inexpensive solution for many patients,” he said.
The trial, called the Study of Soy Isoflavones in Asthma, is administered by the American Lung Association Asthma Clinical Research Centers.
The nationwide study will enroll 380 asthma patients age 12 and older who are taking either inhaled corticosteroids or a leukotriene modifier and still have uncontrollable symptoms. All participants must also have low levels of soy in their diet.
Castro said poorly controlled asthma includes: Feeling short of breath more than once a week, waking up at night more than once a week from asthma symptoms or using rescue inhalers a couple times a week.
Over the 24-week study, participants will continue their medications and be randomly assigned to receive soy isoflavones or placebo tablets. They will be paid $430 for time spent recording daily symptoms and visiting a clinic nine times for asthma tests.