Traditionally, wheezing has only been treated with prescription medications. However, newer research shows that fish oil can decrease the severity of wheezing as well. 

Specifically, the addition of omega-3 fatty acids into the diet can decrease wheezing. Omega-3 fatty acids* (such as those found in fish) block the production of inflammatory chemicals in the body. These chemicals are responsible for a number of inflammatory processes in the body; some of these cause constriction in the airways, leading to wheezing.

After just three weeks of supplementation with fish oil, study subjects (elite athletes) had significantly decreased lung airway narrowing (wheezing), inflammation and use of their medications.  Supplementation can serve as a beneficial treatment for active and athletic people with asthma. 

In addition to supplementation, people with asthma should pay attention to their diet, limiting ‘inflammatory’ foods such as fried foods, alcohol, and processed/junk foods.  Identifying and removing food allergens is highly recommended as well. 

We recommend supplementing your diet with a purified, high-quality fish oil supplement; this is typically necessary to achieve clinical results like those mentioned above, as dietary intakes rarely contain adequate amounts of omega-3 fatty acids.  Additionally, the majority of seafood today is contaminated with mercury and other chemicals, making it unsafe to consume in large amounts. 

P.S. If you are a vegetarian, evening primrose oil is a good source of omega 3 fatty acids.

*Omega-3 fatty acids include eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). 

Reference:

Mickelborough, TD, Lindley MR, Montgomery GS. Effect of fish oil-derived omega-3 polyunsaturated fatty acid supplementation on exercise induced bronchoconstriction and immune function in athletes. The Physician and Sportsmedicine, December 2008.