FRIDAY, March 6 (HealthDay News) -- Teenage junk-food addicts aren't doing their bodies any favors, and their lungs are no exception.

Researchers have found that diets lower in fruit, vitamins C and E, and omega-3 fatty acids are associated with lower pulmonary function in adolescents.

Jane S. Burns, a research associate at the Harvard School of Public Health in Boston, said the clinical effects may not be obvious to teens or their doctors. "However, it is a matter for concern, because it suggests these children are not developing their optimal, potential lung function," she said. "Later in life, this may have an effect, as lower lung function is linked with earlier morbidity and mortality."

What's more, several studies have reinforced the importance of fruit and antioxidants in the diet for reducing wheeze among asthmatic children, Burns added.

Adolescence is a period of rapid physical change, so it should be no surprise that teens require additional nutrients to grow, develop and stay healthy.

Potato chips and cookies are OK once in a while, says TeensHealth, a project of the Nemours Foundation. But the best choices are whole or unprocessed foods, such as fresh fruits and vegetables, whole grains, low-fat dairy products, lean meats, fish and poultry.

Christine Karpinski, a sports nutritionist in West Chester, Pa., says that certain nutrients, including those found in fruits and fish, are thought to protect the lungs from cell and tissue damage caused by inflammation.

"The lung contains many inherent antioxidant defenses to combat this," she said. "However, there may be an increased need for these nutrients with asthma."

To find out how diet affects lung function in teens, researchers examined data from more then 2,000 12th-grade students in the United States and Canada. The students took lung-function tests and answered questions about their respiratory health.