Understanding food allergies: a guide for parents

Food allergy is an immune system response to eating specific foods or food additives. One study found that eight percent of U.S. children (about 1 in 13) have food allergies. Many babies with symptoms of allergic disease, often in the form of eczema, also go on to develop asthma and/or hay fever at a later age. 

The severity of food allergies can vary from mild to life-threatening so it's important that parents learn to recognize and respond to symptoms.

Is my baby allergic?

One in four children with a family history of allergic disease will develop a food allergy between birth and 7 years of age. Food allergies can be classified into two broad categories: Immediate (IgE mediated) or delayed (non IgE mediated). While immediate food allergies tend to be obvious, even in babies, delayed food allergies can be harder to identify.

  • Immediate food allergies. Symptoms typically occur soon after the causal food has been eaten, and can affect a variety of body parts—itching skin, hives, itching or watery eyes, swelling, nasal congestion, runny nose, dry cough, hoarseness, shortness of breath, wheezing, swelling of the lips and/or tongue, nausea, vomiting, diarrhea, dizziness, and fainting. Anaphylaxis, a severe and life-threatening allergic reaction involving two or more body systems, may occur.
  • Delayed food allergies. Symptoms occur several hours or several days after the causal food has been eaten. Signs are typically gastrointestinal in nature, including delayed onset vomiting or diarrhea and bloody stools.

Parents of newborns sometimes confuse normal fussiness with a medical condition such as food allergy. Normal fussiness tends to occur around the same time each day (often in the evening), and usually responds well to soothing techniques such as skin-to-skin contact, breastfeeding or rocking. In contrast, babies with food allergy may cry for long periods of time, sleep intermittently, and wake suddenly with obvious discomfort. Because fussiness can also be a sign of illness, parents need to be alert for other symptoms as well.

Maternal diet during pregnancy & breastfeeding

In the past, mothers with a family history of food allergy were told to avoid certain foods during pregnancy in an attempt to reduce their child’s risk of food allergy. But there is no evidence to show that restricting a mother’s diet during pregnancy or while breastfeeding reduces the risk of food allergy in her baby. 

Today, pregnant and breastfeeding women are urged to follow a normal diet that includes a wide variety of healthy foods. Most food allergies won’t become evident until a baby begins to eat the allergy-causing food on her own (around 6 months of age or later, depending on the type of food). 

If your baby has a confirmed food allergy, particularly if her symptoms are severe, her health care provider may suggest that you eliminate certain foods from your diet while breastfeeding.

What if my baby is formula-fed?

Despite the plethora of formulas, there is no “best” formula for babies. The majority of non-breastfed babies are fed cow’s-milk based formula, including those with a family history of allergic disease (high-risk babies). Giving high-risk babies partially hydrolyzed (pre-digested) formula does not prevent the development of food allergy.

Babies with confirmed milk allergy are usually given soy-based formula. Many babies (35–50 percent) allergic to cow’s milk will also react to soy, leaving parents who formula-feed with only one option—elemental (amino-acid based) formula. According to the U.S. Food and Drug Administration (FDA), partially hydrolyzed formulas contain cow's milk peptides (potential antigens) and should not be given to babies with a confirmed cow’s milk allergy. If you suspect that your baby is allergic to cow’s milk, talk with her health care provider about feeding options.

Introduction of solids

What do peanuts, cow’s milk, and shellfish have in common? They are among the eight foods (see them here) that account for 90 percent of all food allergies.

Introducing a variety of foods — including common food allergens such as cow's milk products, wheat, and eggs — around 6 months of age may help to reduce the risk of food allergies in some children. 

For parents who wish to reduce their child’s risk of peanut allergy, experts recommend the following:

  • If the infant has no known risk of peanut allergy (no eczema, no diagnosed food allergy), or has only mild-to-moderate eczema, parents can talk with their infant’s pediatrician about introducing peanut-containing foods at around 6 months of age.
  • If the infant has risk factors like severe eczema or an egg allergy, the pediatrician may recommend skin-prick testing before introduction of peanut-containing foods. Infants with no reaction may be started on a diet that includes small amounts of peanut. Those with a mild reaction may try a “food challenge,” with a pediatrician or allergist giving the infant a small amount of a peanut-containing food and watching closely for any reaction. Children without a reaction may be started on peanut-containing foods.
Click here to learn more about peanut allergies and tips for introducing peanut-containing foods.

Managing food allergies

While many children outgrow their food allergies over time — with the exception of peanut allergy which persists in 80 percent of cases — it's important to create a manageable system or routine to help ensure the safety of your child. Here are some tips to help parents and caregivers:

  • Always read labels. Check food labels, and ask about ingredients in foods served in restaurants, child care centers, and schools. Be mindful that product ingredients can change at any time and products unrelated to nuts can still contain nut flours.
  • Avoid cross-contamination at home. If everyone in your household isn't following an allergen-free diet, be sure to thoroughly wash items (utensils, dishes, cook ware, cutting boards) that come in contact with your child's allergen before using them again, preferably in hot, soapy water or the dishwasher.
  • Have an allergy treatment plan. Consult your child's health care provider on what steps to take if your child is exposed to allergens, and have them fill out a "Food Allergy & Anaphylaxis Emergency Care Plan" (download here). Keep copies of the plan at your home and with your child's caregivers and teachers (preferably attached to your child's medication). 
  • Always carry your child's medication. Children at risk for a severe allergic reaction (i.e. anaphylaxis) should always have an epinephrine auto-injector (more commonly known as an EpiPen) handy, along with instructions on when and how to administer it. You should also keep an antihistamine (such as Benadryl) on hand and consult your child's health care provider on proper dosing. 
  • Inform caregivers and teachers. Have your child wear a medical bracelet that identifies his allergy and prescribed treatment, and make sure adults responsible for your child’s well-being are aware of any food allergies. In addition to your allergy treatment plan, make sure medication is kept on-hand and that adults know how to administer it. 
  • Consider allergen-free environments. Young children are subject to greater risk of accidental exposure since they cannot read labels and may not yet be able to advocate for themselves. Many daycares and schools have adopted rules to reduce exposure on site. The Centers for Disease Control and Prevention (CDC) has developed a set of guidelines that can help.
  • Alert restaurant staff. Before you order food in a restaurant, whether it's five star or fast food, let the person taking your order know that your child has a food allergy so they can ensure there is no cross-contamination in the kitchen. 
  • Keep a food diary. If you have observed food allergy symptoms in your breastfed baby, you may want to speak to your health care provider about eliminating one food at a time from your diet in an effort to identify the culprit.

And always remember, your child should be taken to the emergency room any time epinephrine has been administered so he can be monitored for signs of a delayed reaction or biphasic anaphylaxis, where a patient initially seems to have successfully recovered from the first allergic reaction but has a second onset of anaphylaxis without being exposed to the allergen again. 

Last updated August 24, 2017

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