A food allergy, according to Dr. Jose M. Saavedra, is the result of an immune reaction by the body to normally harmless substances in foods. The substances that cause the problems are called allergens or antigens. These are part of food proteins. Sugars or fats do not cause allergies.

For a variety of reasons, some children’s immune system releases antibodies and histamines in response to these allergens. This is where the nasal congestion and watery eyes come from. In the United States, the number of food allergies has doubled in the last 20 years. Today 1 in 5 infants will develop an allergy and 30-60% of these can be attributed to food sources, with the most common allergen being cow’s milk protein.

Food allergies, which affect about 6% of children younger than 3 years of age, can have the following symptoms (in order of severity):

• Skin reactions. The rash is called atopic dermatitis or eczema and it is a red, itchy rash that can become chronic and lead to dry excoriated skin. The child will constantly scratch, become irritable and develop sleep disturbances. This is the most common skin reaction in infants. Hives, which are acute, sudden, red, itchy blotches that usually disappear after a short time is more common in adults.


• Intestinal reactions occur mostly in infants. Inflammation of the intestine can lead to mild symptoms such as colic all the way to severe inflammation and blood in the stool.


• Respiratory reactions such as allergic rhinitis (hay fever) and asthma are more prevalent in adolescents and adults and more commonly related to proteins in the air (mold, pollen, animal dander, etc) than from food proteins.


• The most serious reaction is anaphylaxis. This is a generalized allergic reaction that leads to fainting, drop in blood pressure, difficulty breathing and potential death. It is rare, but can be lethal and is frequently the cause of death to peanut allergy.

Which foods cause the most allergic reactions in pediatric cases? In order of the most common cause:

• Protein in cow’s milk. Almost 90% of allergies in infants is caused by the protein in cow’s milk. By ages 4-5, most children will tolerate the milk without an allergic response, but some never outgrow it.


• Soy protein


• Eggs


• Wheat and gluten


• Peanuts or shellfish. Most children are unlikely to outgrow this allergic reaction and it can be potentially fatal in rare cases


• Tree nuts


• Corn products.

As children grow, their reactions to the proteins changes and can become increasingly more severe. This progression of manifestations is called the ‘atopic march’.

How can parents prevent food allergies from occurring?

• Breastfeeding is one of the most effective ways to prevent your child from developing food allergies. Interesting, there is no allergy to human milk, but there may be one to breastfeeding because occasional traces of cow’s milk protein in mother’s diet can pass through the milk.


• Routine standard formulas are made with cow milk protein. It is therefore no surprise that this is the most common food allergen in infants. The goal of prevention in a baby that does not exclusively breastfeed is to decrease the chances the baby’s immune system gets sensitized by cow milk protein.

Hydrolyzed or pre-disgested protein formulas reduce the risk of allergies compared to intact protein formulas. Unfortunately, they are expensive and taste awful. Today, partially hydrolyzed protein formulas are available. They taste and cost like regular intact cow milk protein formulas.

• The in utero environment can also affect the newborn’s allergic reaction. Smoking while pregnant (or second hand smoke) and a poor diet can set the stage for an allergic child.

The introduction of solid foods must be done carefully to prevent an immature digestive system to absorb foreign proteins that would normally not pass through the blood system. Once a child has been sensitized to a protein, it is a bit easier to treat the allergy while they are still on formula rather than eating solid foods.

Another way parents can prevent food allergies is to carefully read food labels. Since 2000, the FDA has presented information on allergen risk and labeling requirements at more than a dozen locations nationwide. The National Food Processors Association adopted a ‘code of practice’ that calls for listing the 8 most common food allergens in plain language, although this is still voluntary.

Make sure that you are in control of all meals and snacks your infant consumes. Speak with her caregivers, play groups, teachers, family members and play dates about the importance of being vigilant about food allergies. Nurturing your child with proper foods for maximum health will last her a lifetime.

For more information, log on to

www.foodallergy.org