Asthma is a chronic inflammation of the lower respiratory tract, characterized by variable and recurrent airflow obstruction and bronchial hyperreactivity. Specific symptoms of asthma are primarily: wheezing, shortness of breath, tightness of the chest and persistent cough. In recent years, a continuous increase in the incidence of chronic diseases, including allergic diseases, has been observed in both adults and children. Asthma is a serious health problem in the world, especially in developing countries, as it affects up to 300 million people, and in Poland – 4 million. The increasing amount of scientific evidence confirms the potential impact of environmental factors on the development of this disease. A variety of nutrients are believed to have a positive effect on the prevention and/or treatment of asthma. Particular importance is attributed to n-3 polyunsaturated fatty acids, antioxidants (vitamin A, E, C, selenium), vitamin D and magnesium. Moreover, mother’s diet during pregnancy and baby feeding also seem to be important. It is believed that maintaining a well-balanced diet, in addition to conventional pharmacotherapy, may reduce the frequency and severity of asthma symptoms.