Poor Diet Affects Respiratory Health of Teenagers

Frank Speizer, M.D., Douglas Dockery, Sc.D., Joel Schwartz, Ph.D., and Brent A. Coull, Ph.D.
Harvard School of Public Health
R01ES008391, T32ES007069, and P30ES000002

New epidemiologic research on teenagers in North America shows that a diet poor in essential vitamins and minerals, and other antioxidant compounds is linked to increased risk for developing respiratory conditions including asthma and reduced lung function. The study was conducted in high school seniors in 12 communities in the U.S. and Canada. The results suggest that higher dietary intake of antioxidant and anti-inflammatory micronutrients, such as vitamins A, C, and E and omega-3 fatty acids, is linked to lower reports of cough, respiratory infections, and less-severe asthma symptoms.

Lung growth and development parallels growth in physical stature; therefore the study subjects in late adolescence were near their peak of lung function. Analysis of questionnaires showed that 33 per cent of the study subjects’ diets were below the USDA recommendations for fruits, vegetables, essential vitamins and minerals, etc. One-third of the teenagers were overweight, another contributing factor for asthma; 72 percent did not take multivitamins, and 25 percent smoked. The results showed that low intake of vitamins A and C, fruits and vegetables, and omega-3 fatty acids such as those found in fish and algae, was linked to reduced lung function, increased wheeze, greater risk of asthma, and symptoms of chronic bronchitis. These risks were highest among study subjects with the poorest diets who also smoked.

This study adds to the body of knowledge that a healthy diet high in antioxidants is important for proper lung growth and development to reduce the risk of asthma as well as improve the general health of teens. The researchers conclude that snacks of fresh fruit and a simple nutritious family meal would be easy ways to helps teens consume the proper amounts of essential nutrient.

Citation: Burns JS, Dockery DW, Neas LM, Schwartz J, Coull BA, Raizenne M, Speizer FE. Low dietary nutrient intakes and respiratory health in adolescents. Chest. 2007 Jul;132(1):238-45.