Childhood asthma is a significant health problem. In 2013, nearly 50 percent of asthmatic children ages 5 to 17 reported one or more missed school days because of asthma. Although the relationship between nutrition and asthma is still being established, there is little doubt that a healthy diet can have an impact on asthma. There is no single diet recommended for children with asthma, but the so-called Mediterranean diet -- low in saturated fats, rich in fruits and vegetables, and high in fiber -- has been associated with reduced asthma symptoms. Understanding good nutrition and potential dietary influences on your child's asthma can be an important part of your overall strategy for symptom control.
Eating lots of fruits and vegetables is associated with better respiratory health and improved asthma symptoms in children, according to a large international study published in the April 2010 issue of "Thorax." The same article noted past studies that have found a link between antioxidants and other nutrients in fresh fruits and vegetables and better lung function and fewer asthma symptoms. Specifically, a high consumption rate of apples and pears was linked to less tightening of the airways, or broncho-reactivity, in a study of young adults in Australia. Nuts and seeds rich in flavonoids and other compounds with anti-oxidant effects help fight inflammation, which may boost respiratory health.
Fish can be a good source of omega-3 fatty acids and is considered part of a healthy diet. With respect to respiratory conditions of childhood, studies of fish consumption have had contradictory findings -- some suggesting positive effects, and some suggesting no improvement or even worsening of asthma. Generally, fish provides an abundance of vitamins and minerals, in addition to being rich in omega-3s, all thought to have beneficial effects on inflammatory disorders and lung function.
In a study of 1,921 adults published in the January 2016 issue of "Annals of the American Thoracic Society," low fiber intake was associated with diminished lung function, while a diet rich in fiber was associated with healthy respiratory function. Fiber has anti-inflammatory properties and may help guard against against allergic diseases such as asthma. Dietary fiber also contains prebiotics -- nutrients that help "feed" or promote the growth of good bacteria in the gut, some of which may help fight inflammation. Therefore, whole grains like brown rice and legumes like lentils and pinto beans are recommended as part of a healthy diet.
Foods That Are Bad for Asthma
Just as important as consuming fresh, nutrient-rich foods is avoiding unhealthy choices. Fast food and particularly fast-food hamburgers have been associated with a higher prevalence of asthma flareups. Reasons for the association are unclear, but it's possible industrial processing, hydrogenated vegetable fats and trans-fatty acids may be to blame; meat consumption in general is not believed to be a contributing factor to asthma. Drinks sweetened with high fructose corn syrup have been linked to asthma in U.S. high school students. Beverages with excess free fructose (EFF) -- which includes apple juice, drinks with high fructose corn syrup and soft drinks -- have also been linked to asthma in children.
Food Allergy, Sulfites and Asthma
While food allergens are not common asthma triggers, there is a catch: Anaphylaxis or a severe allergic reaction to foods can mimic an acute asthma attack, at least initially. Additionally, sulfites, which can trigger asthma symptoms or serious allergic reactions in sensitive children, are present in some foods and are used as preservatives for shrimp, dried fruit, processed potatoes, beer and wine. People who have both food allergies and asthma are at a higher risk for potentially fatal anaphylactic reactions, so those allergic to specific food items or allergens such as peanuts, strawberries or other food items should take special care.
Excess Weight and Managing Asthma
Proper asthma control requires working with your child's doctor, but healthy eating at home is important in more ways than one. Excess weight and obesity may result when there is a mismatch between calories consumed and calories spent. Excess weight, in addition to poor nutrition, is increasingly recognized as risky for health in general -- and for asthma, specifically. Obesity has been linked to decreased efficacy of inhaled corticosteroids, which are often prescribed for asthma. Asthmatic children who are also overweight are encouraged to lose weight.