Some parents may look for ways to prevent their children from developing asthma and allergies. Many experts have recommended exclusive breastfeeding for several months before introducing other foods.
New research suggests that exposing babies to certain foods at earlier ages, in addition to breastfeeding, might help reduce the chance that the baby will develop allergies.
Researchers in Finland looked at the link between the age that children first ate certain foods and whether or not they developed asthma or allergies by 5 years of age.
The researchers found that early introduction of certain foods like eggs, oats, wheat and fish was associated with a lower likelihood that the child would develop asthma or allergies.
Bright I. Nwaru, PhD, of the School of Health Sciences at the University of Tampere in Finland, and colleagues studied the relationship between how long a child was breastfed, how old they were when they first ate certain foods and their likelihood of developing allergies or asthma by age 5.
To carry out the research, the authors used data from 3,781 children that had participated in a previous large-scale study in Finland. The larger study was the nutrition part of the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) study.
For the first part of the original DIPP study, babies that were born with susceptibility to type 1 diabetes were recruited from three university hospitals. The babies were monitored at three- to 12-month intervals to check whether they had developed diabetes.
For the second part of the DIPP study, the focus was on nutrition. Participants in this part of the study who had been born between 1996 and 2004 were invited to become part of the allergy study at the age of 5.
Researchers asked caretakers about their children's diets. Age-specific questionnaires were administered at the ages of 3, 6 and 12 months. A follow-up form was also provided for recording the age at which new foods were introduced into the children’s diets.
In the questionnaires, the caretakers were asked about breastfeeding, infant formula and cow’s milk use, dietary supplements and the solid foods the children had been exposed to.
The form that asked for the date for each new food was introduced to the child was kept as a log book in the home until the child turned 2.
Of most interest to the researchers was how old the child was when they first had cow’s milk. They also examined how old the child was when they first started eating root vegetables (potatoes and carrots), fruits and berries, wheat, rye, oats, and barley, cereals from maize, rice, millet and buckwheat. Meat, fish, egg exposures were examined as well.
Blood samples were evaluated for evidence of egg, cow’s milk, fish, wheat, house dust mite, cat, timothy grass and birch allergies.
The researchers found that early introduction of certain foods was associated with a lower likelihood that the child would develop asthma or allergies by age 5.
They found that children that were introduced to wheat, rye, oats and barley before they were 5 and a half months old had lower rates of asthma and allergies. This was the same for children that ate fish before 9 months of age and egg before 11 months of age.
The researchers also found that babies that were breastfed for nine and a half months or more had a lower likelihood of developing asthma. The benefits of breastfeeding were associated with the length of total time the child had been breastfed, even if they were eating other foods during that time.
“Our data indicate that early introduction of complementary foods, particularly cereals, fish, and egg (respective to the timing of introduction of each food), seems to confer protection against the development of both asthma and allergies,” wrote the authors.
They also noted that “long duration of total breastfeeding, rather than its exclusivity, seems to be beneficial” against asthma.
“These findings highlight the emerging suggestion that introducing complementary foods early while continuing breastfeeding might be more important as a preventive strategy for the development of allergies and asthma in childhood,” the authors concluded.
“This study adds to an exciting and evolving literature regarding suggested approaches to infant feeding in regards to breast feeding and introduction of table food,” said John Oppenheimer, MD, a pulmonary and allergy specialist and dailyRx Contributing Expert.
“From this study, it would appear that longer duration of total breast feeding - not exclusive breast feeding - and early introduction of wheat, rye, oats, barley, fish and egg decrease the risk of developing asthma, allergic rhinitis and allergic sensitivity in childhood,” he said.
“I am hopeful that with further research we will even better fine-tune our recommendations and in so doing reverse the trend in increased allergic disease,” Dr. Oppenheimer added.
The study was published in the January issue of The Journal of Allergy and Clinical Immunology.
The research was funded by the Academy of Finland, the Prevaller Consortium, the Foundation for Pediatric Research, the Tampere Tuberculosis Foundation and others.
Three of the researchers reported potential conflicts of interest. Support for some of their professional endeavors came from organizations that are involved in medical research, universities in Finland and government ministries. The other authors report no conflicts of interest.