According to research presented in the American Journal of Respiratory and Critical Care Medicine (2001; 164:1823-1828), eating apples reduce the risk for asthma. 1,500 adults in the United Kingdom were questioned about their eating habits. The respondents were particularly questioned about foods that were high in antioxidants and trace minerals—in other words, fruits and vegetables.
Antioxidants are nutrients like vitamins C, E, selenium and plant pigments (which protect the plant) like carotenes and flavonoids. Oxidizing chemicals (that literally “fire” an electron) are like chemical “bullets”. Antioxidant nutrients are like chemical “bullet-proof vests”. Antioxidants protect against these chemical irritants and seem to protect from many kinds of disease—including asthma. Oxidation can cause inflammation and asthma is a disease of inflamed airways.
People who ate at least two apples per week had a 22%–32% lower asthma risk than those who did not. Specific flavonoids may protect against asthma because flavonoid containing foods other than apples were not associated with lower asthma rates.
Selenium consumption was also looked at. Those who consumed between 54 and 90 micrograms of selenium per day were half as likely to have asthma compared to those who consumed between 23 and 30 micrograms per day. The RDA for selenium in the United States is 55 micrograms per day.
In other research, published in the journal Allergy (December, 2000; 55: 1184-1189), investigators found that increased lycopene consumption seems to reduce the incidence of exercise-induced asthma. Lycopene is a carotenoid (plant pigment that acts as an antioxidant). It was a small study, with 20 subjects. After one week a little over half of the subjects given lycopene showed significant protection against exercised induced asthma. Patients takinglycopene had higher blood levels of lycopene compared to the placebo group. No changes were found in levels of other carotenoids or other antioxidants.