New Study Reviews Use of Common Nutritional Supplement Isoflavone in Treatment of Uncontrolled Asthma | American Lung Association

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New Study Reviews Use of Common Nutritional Supplement Isoflavone in Treatment of Uncontrolled Asthma

(May 26, 2015) - CHICAGO

A new study from the American Lung Association Airways Clinical Research Centers (ACRC) Network examines if a common nutritional supplement will improve the health of those with poor asthma control.

Soy isoflavone nutritional supplements are commonly used to treat several chronic diseases, and some data has suggested they may be an effective treatment for patients with poor asthma control. A new study, "Effect of a Soy Isoflavone Supplement on Lung Function and Clinical Outcomes in Patients with Poorly Controlled Asthma: A Randomized Clinical Trial," published today in the Journal of the American Medical Association examines if soy isoflavones improve asthma control in adolescent and adult patients with poorly controlled asthma. This study was co-funded by the American Lung Association and National Heart, Lung, and Blood Institute (NHLBI).

"Nutritional supplements are commonly used by people to treat and prevent disease and improve their health, yet oftentimes there is little data to prove that the supplement is actually effective in treating certain diseases, including asthma," said Lewis Smith, M.D., the report's lead author and professor of medicine at Northwestern University's Feinberg School of Medicine. "Through this randomized, double-blind, placebo controlled study, we examined whether this commonly used supplement truly improves uncontrolled asthma."

The study found that among adults and children aged 12 years or older with poorly controlled asthma, while taking a controller medication, use of a soy isoflavone supplement, compared with placebo, did not result in improved lung function or clinical outcomes, including symptoms, episodes of poor asthma control, or systemic or airway inflammation. The findings of this study suggest that this supplement should not be used as a therapeutic option for patients with poorly controlled asthma.

Soy isoflavone supplements have been used for years to treat a number of conditions including hot flashes and osteoporosis. In 2012, nutritional supplement sales reached nearly $12 billion, and are expected to reach more than $15 billion by 2017.

"Through identifying what does not work in the treatment of uncontrolled asthma, we've potentially saved consumers from spending thousands of dollars on an ineffective treatment," said Smith.

"Beyond finding that soy isoflavone supplementation in patients with asthma is not beneficial, this study is an excellent example of why it is so important to perform well-designed, placebo-controlled studies when an association is found between a specific nutrient and a disease outcome," Smith said. "It also supports the idea that an overall healthful diet and not individual components may explain the association found in epidemiology studies of diet and disease."

The American Lung Association Airways Clinical Research Centers (ACRC) Network is the nation's largest not-for-profit network of clinical research centers dedicated to asthma and COPD treatment research, attracting some of the best investigators nationwide. The ACRC Network conducts large clinical trials that will have a direct impact on patient care.

"The ACRC network supports excellent studies that have had major impact on asthma treatment," said Harold P. Wimmer, National President and CEO of the American Lung Association. "Collaborations between not-for-profit organizations like the American Lung Association and government funders like the National Institutes of Health play an important role in advancing the understanding of diseases like asthma and its treatment."

For media interested in speaking with an expert about asthma or this study, contact the American Lung Association at [email protected] or 312-801-7628.

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