Prevention of Food Allergy in Infants: Delayed Introduction of Solid Foods

Allergic disease is more common than ever, and it is not surprising that more people with allergies are asking how they might be able to decrease the chance that their children will have allergies. One particular question is in regards to the introduction of solid foods into the diet of infants at risk for allergies. Various studies show that delaying the introduction of various foods into the diets of infants may delay or prevent the development of food allergies.

The American Academy of Pediatrics (AAP) recommends exclusive breast-feeding of infants for at least the first 6 months of life. This is followed by the gradual introduction of solid foods from age 6-12 months, as well as continued breast-feeding for 12 months or longer.

However, many mothers are not able to continue exclusive breast-feeding for 6 months, due to the time commitment, nutritional needs of the infant, as well as the fact that many infants are developmentally ready for other foods prior to this time.

When solid foods are introduced, the AAP recommends that single-ingredient foods are added one at a time, with a trial lasting many days prior to additional foods being added. This serves the purpose of knowing which food is to blame should the infant experience an adverse reaction (allergy or intolerance) as a result.

Does the Early Introduction of Solid Foods Cause Food and Other Allergies?

Studies show that the introduction of solid foods before 4 months of age increases the risk of atopic dermatitis until the age of 10 years. In addition, the use of cow’s milk-based formulas in early infancy has been associated with the development of cow’s milk allergy.

In addition, one study showed that when solid foods were given to infants less than 8 weeks of age, there was a higher risk of coughing and breathing problems at 3 to 6 months of age.

Another study that delayed the introduction of solid foods in infants until after 6 months of exclusive breast-feeding showed lower risks of atopic dermatitis and asthma later in childhood. However, it is not clear in other studies whether this represents prevention of the onset of allergic disease (including to foods) or just a delay in the onset of disease.

Which Solid Foods Should be Added and Avoided?

The choice of what foods to add to an infant’s diet is dependent on various considerations:

• Nutritional considerations
• Safety considerations (food hygiene)
• Behavioral considerations (appropriate texture and form)
• Low allergy potential

In general, the most common food allergies are the types of foods that should be avoided in infants.

In addition, allergy to fruits and vegetables can be a common problem in young children, especially when introduced into the diet at an early age. This typically is more of a problem with fresh fruits and vegetables, as many allergens present in fruits and vegetables are easily broken down through cooking and processing. A notable exception is celery, which continues to be allergenic even after cooking.

Allergy to fresh kiwifruit is becoming more common as the popularity of this fruit is increasing. Cooked kiwifruit is tolerated in children with known allergy to the fresh fruit.

Timing of Introduction of Solid Foods in the Diet of Children

For children with a family history of allergies, the AAP recommends refraining from introducing these allergenic foods into the child's diet until he or she reaches the following ages:

• Cow’s milk and other dairy foods (age 12 months)
• Egg and egg-containing foods (age 24 months)
• Peanuts and tree nuts (age 36 months)
• Fish and shellfish (age 36 months)

Summary of Dietary Recommendations

The American College of Allergy, Asthma and Immunology (ACAAI) recommends the following regarding the introduction of foods into the diet of children, particularly for those at risk for the development of allergy (such as with a family history of allergies):

• Exclusive breast-feeding, with the avoidance of cow’s milk formulas, is recommended for at least the first 6 months, with the continuation for 12 months or longer
• Introduction of supplemental foods at 6 months of age, while avoiding the most common causes of food allergies (cow’s milk, egg, peanut, treenuts, fish and shellfish)
• Single-ingredient foods should be added one at a time, with many days passing before adding additional new foods
• Cooked and/or processed foods are preferred to fresh forms, especially when allergies to the fresh forms are common (fruits, meats)

Want to keep learning? Find out about allergy to food additives and preservatives.

Source: Fiocchi A, Assa’ad A, Bahna S. Food Allergy and the Introduction of Solid Foods to Infants: A Consensus Statement. Ann Allergy Asthma Immunol. 2006; 97: 10-21.

DISCLAIMER: The information contained in this site is for educational purposes only, and should not be used as a substitute for personal care by a licensed physician. Please see your physician for diagnosis and treatment of any concerning symptoms or medical condition.