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Nutritional Supplements for Asthma? Not So Fast.

Woman looking suspiciously at a supplement bottle label

Who can blame asthma sufferers for looking for different ways to alleviate their asthma symptoms? Many are desperate for a treatment for the wheezing, coughing and sometimes even the drowning-on-land feeling associated with asthma. One purported remedy is the nutritional supplement soy isoflavone.

Soy isoflavone supplements have been used for years to treat a number of conditions including hot flashes and osteoporosis. Nutritional supplements as a whole have been used commonly by people to prevent, treat or manage disease, sometimes without truly knowing if the supplement is actually effective. It sounds natural after all, so what's the harm? Well, aside from the fact that the supplement may not be effective, the problem is that it could potentially cause side effects or interactions with other medications. So through the Lung Association's Airways Clinical Research Centers Network (ACRC), Lewis J. Smith, MD took a closer look.

Smith's randomized, double-blind, placebo controlled study "Effect of a Soy Isoflavone Supplement on Lung Function and Clinical Outcomes in Patients with Poorly Controlled Asthma: A Randomized Clinical Trial," found something interesting: soy isoflavones didn't help reduce asthma symptoms at all. 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.

"Beyond finding that soy isoflavone supplementation in patients with asthma is not beneficial, this study clearly demonstrates why it is so important to perform well-designed, randomized and controlled studies when an association is found between a specific nutrient and a disease outcome," Smith said. This can save people money (In 2012, nutritional supplement sales reached nearly $12 billion, and are expected to reach more than $15 billion by 2017) and also avoid any negative interactions or side effects. "It also supports the idea that an overall healthful diet and not individual components [supplements] may explain the association found in epidemiology studies of diet and disease, he added."

Learn more about asthma research happening in our Airways Clinical Research Centers Network.

Related Topics: Health & Wellness, Research,

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