Childhood asthma: look at the diet

Two recent studies highlight how vitamins, antioxidants and essential fatty acids in a child’s diet benefit lung function and reduce the risk of asthma.

In a study at the University of Southern California in LA, researchers investigated the possible relationship between children’s lung function and their intake of fruits, vegetables and juices. These foods provide beneficial dietary antioxidants, including vitamin C, which has been shown to help improve lung function on its own. Using data available from the Children’s Health Study 1997-1998, which involved about 2,566 children, the researchers found a distinct association between lower intake of fruits, vegetables and juices and an increased likelihood of poor lung capacity, poor lung function and asthma. Nutritionists recommend five to 10 servings of fruits and vegetables each day, including at least one citrus fruit.

Asthma may be also be linked to essential fatty acid intake, say researchers at Curtin University of Technology in Australia. Their study looked at how childhood asthma may be affected by the ratio of omega-6 to omega-3 fatty acids in the diet. While the average Canadian consumes 10 to 20 times more omega-6 than omega-3, the recommended ratio is actually 4:1, omega-6 to omega-3. Looking at the diets of 335 children (aged 6-8 years old), some with asthma and some without, the researchers found that too much omega-6 and not enough omega-3 was positively associated with a higher risk of childhood asthma. The researchers recommend obtaining more omega-3 (from fish oils) and cutting down on omega-6 (from vegetable oils).

Sources: Am J Epidemiol. 2003 Sep 15;158(6):576-84; J Asthma. 2004;41(3):319-26