Asthma is an inflammatory respiratory illness characterized by mild to severe difficulty in breathing. This is caused by constriction and swelling of the airways, along with an increase in secretions of mucus, which plugs up the smaller passages. As a result, air cannot get into or out of the lungs as easily as it usually does. Wheezing results as air squeaks through the narrowed and inflamed air passages. An asthma attack can cause such shortness of breath and poor oxygen intake that a child may need to be hospitalized.
Asthma can be triggered by a variety of things, including exposure to pollen, dust, feathers, molds, animal dander, pollution, cigarette smoke or cold dry air, as well as by an upper respiratory infection, exercise, stress or even an underlying food allergy.
Asthma affects approximately 7 percent of the population of the United States. Although it occurs at all ages, it is most common in children younger than 10. Possible reasons given to explain the rise in asthma include:
- Increased stress on the immune system due to factors such as greater chemical pollution in the air, water, insect allergens (dust mites), and food
- Earlier weaning and earlier introduction of solid foods to infants
- Food additives
- Higher incidence of obesity
- Genetic manipulation of plants, resulting in greater allergenic predispositions
In a recent study, researchers investigated the use of fish oils during pregnancy to see if it could prevent childhood asthma. A total of 736 pregnant Danish women were randomized to receive 2.4 grams of EPA and DHA daily from a fish oil supplement or a placebo during the third trimester. Their children (695) were then followed for 5 years. The children of the mothers who received fish oil had a reduction of 30.7 percent in asthma or persistent wheeze. Less lower respiratory infections also occurred in the fish oil group. The most significant results in prevention of asthma or persistent wheeze were seen in the children of mothers who had the lowest dietary intake of EPA and DHA.
This recent study explores the higher intake of fish oils during pregnancy, which may be useful for supporting immunity and reducing the incidence of childhood asthma.
Bisgaard H, et al. Fish oil derived fatty acids in pregnancy and wheeze and asthma in offspring. NEJM 2016 Dec 29; 375: 2530