Although there's no one cause of food allergies, they're certainly on the rise among children in the United States. According to the Centers for Disease Control and Prevention (CDC), the prevalence of food allergies among 0 to 17-year-old children in 2009 to 2001 was 5.1%, up from 3.4% in 1997 and 1999. Despite this uptick in food allergy incidence, emerging evidence suggests that some dietary steps may help prevent food allergies and the toll they take on children and their families.
In a new study published in Journal of Allergy and Clinical Immunology, researchers from the University of Southampton in the United Kingdom looked at prospective food diary data kept by mothers of infants to determine whether the infant diet during the first year of life was linked with the development of food allergy. Lead researcher Kate Grimshaw, PhD, RD and her colleagues found that a dietary pattern in later infancy that was rich in fruits, vegetables, and home-prepared foods was associated with less food allergy by the age of two years. One reason cited by the researchers for their results is the presence of vitamin C, beta-carotenes, folate, and oligosaccharides in fruits and vegetables. Such nutrients, they note, may have immune-boosting and anti-inflammatory benefits. The apparently protective dietary pattern was also associated with eating more home-prepared foods and fewer processed convenience foods, something the researchers suggest may also protect against the development of food allergies.
"Even though studies like this one are compelling, we still don't know a surefire way to prevent food allergies," says Kristi Winkels, a registered dietitian nutritionist who specializes in food allergies and intolerances. She adds, "My first thought when I read about this study was that it isn't consistent with my own experience as a mom. When my first son was a baby, I breastfed him exclusively until he was four months old. I then introduced solids starting with rice cereal and followed that with variety of fruits and vegetables that I prepared myself. Despite that, he was diagnosed with multiple severe food allergies (egg, dairy, wheat and peanut) when he was nine months old. With that said, I think everyone can benefit from eating fewer processed foods whether they are trying to prevent food allergies or not."
Although Winkels acknowledges that there's a lot we still need to learn about the development and possible prevention of food allergies in children, she advises all parents to offer their infants a variety of fruits, vegetables and minimally processed grains and proteins starting at four to six months of age. She recommends introducing each new food two to three days apart and to watch for any symptoms of an allergic reaction (hives, lips swelling, irritability, etc.). She adds, "It's crucial for parents who have allergies themselves to be even more aware of the signs and symptoms of an allergic reaction since their children are at higher risk of developing food allergies."
The American Academy of Allergy, Asthma & Immunology (AAAAI) recommends exclusive breast-feeding for at least four to six months of age to reduce the incidence of cow's milk allergy in the first two years of life. For those who cannot breast-feed, the AAAAI recommends hydrolyzed formula which appears to offer advantages to prevent cow's milk allergy. Also, when complementary foods are introduced and tolerated between four and six months of age, parents are urged to introduce highly allergenic foods including cow's milk protein (except for whole cow's milk), egg, soy, wheat, peanut, tree nuts, fish and shellfish at home (rather than at a day care or at a restaurant). According to the AAAAI, there's evidence that introducing such foods early may actually reduce food allergy risk among children.
Image of baby eating red strawberry via Shutterstock.