It is a known fact that air pollution can influence the risk and severity of asthma. And now, there has been emerging evidence that diet can play a vital role in treating asthma.
A new study had found that eating foods rich in omega-3 fatty acids, such as salmon, sardines, lake trout, and even flaxseeds and walnuts, can reduce asthma symptoms in city kids who are exposed to relatively high levels of air pollution.
Dr. Emily Brigham, the co-author of the study and a pulmonologist at Johns Hopkins University said, “We know that asthma is a disease that’s driven by inflammation. As our bodies digest fish, the omega-3 fatty acids generate byproduct molecules known as ‘pro-resolving mediators’ that make their way into our lungs. They help to resolve inflammation.”
Considering the anti-inflammatory effect, Dr. Brigham and her team had a hunch that foods rich in omega-3 fatty acids can help attenuate the effects of air pollution in kids with asthma.
Dr. Brigham said, “What we found was that higher reported-intake of omega-3 was linked to reduced effects of indoor particulate matter on symptoms. Kids who were eating more omega-3’s seemed to be more resilient to the effects of PM.”
The researchers have also assessed the intake of omega-6 fatty acids, which are found in vegetable oils and are abundant in many processed foods containing oil. Generally, Americans eat more omega-6 acids than omega-3 acids. And the study found that kids who consumed more omega 6 fatty acids had more severe asthma symptoms.
Dr. Brigham explained the role of omega-6 fatty acids in inflammation is a bit complicated. Leukotrienes in omega-6 acids have been shown to be pro-inflammatory, which are known to be responsible for causing inflammation in asthma.
Since it is an observational study, researchers were not able to prove that omega-3 fatty acids actually decrease asthma symptoms or higher intake of omega-6 fatty acids aggravated the symptoms. However, the findings provide strong evidence that omega-3 fatty acids have anti-inflammatory properties.
Kym Gowdy, an assistant professor of pharmacology and toxicology at East Carolina University, said, “This study adds to a growing body of literature that suggests that diet — western, Mediterranean, etc. — can influence the health effects associated with air pollution exposure.”
She pointed out to a recent study that is published in the journal Circulation, which found a Mediterranean diet reduced the risk of death from heart disease related to long-term exposure to air pollutants.
“The [new] study by Dr. Brigham supports the overall notion that nutritional status is an important factor that should be considered to enhance protection against air pollution,” explained Neil Alexis, a professor at UNC School of Medicine in Chapel Hill, N.C.
Alexis noted that another study has found that antioxidant supplements may help attenuate the effects of ozone exposure on the small airways of children with moderate to severe asthma. According to a separate 2018 study, vitamin E helped reduce the inflammatory effects of asthma.
Typically, a diet rich in vegetables, fruits, nuts, and seeds and healthy fats, including omega 3 fatty acids, has many documented health benefits. When it comes to consuming enough omega-3 fatty acids, the U.S. dietary guidelines recommend adults to consume 8 ounces of seafood a week and young children a little less.
