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Food Allergies

Food allergies are relatively common—6 to 8 percent of kids develop them. How would you know if your child is one of them—and what would you do if she were? Here, what you need to know.

Where do Food Allergies Come From?

A food allergy is when the body's immune system mistakenly recognizes a certain food as harmful—and responds by releasing chemicals called histamines in an effort to fight it off. The histamines, in turn, cause a variety of symptoms that can range from a mild rash to difficulty breathing.

Food allergies run in families, so babies whose parents have allergies are at higher risk (particularly if both parents do). But more and more babies without a family history are developing allergies, too.

Preventing Food Allergies

Whether or not you have a family history of food allergies, there are lots of ways to lower your child's chances of developing one.

If you or your partner has food allergies:

  • Breastfeed. Your milk is rich in proteins that may help reduce your child's risk of developing allergies. (While you're nursing, your pediatrician may recommend that you avoid eating common food allergens, such as milk or nuts.)
  • If you're bottle-feeding, use a hypoallergenic formula.
  • Be careful when you introduce certain foods into your child's diet. Wait until he turns at least 1 before giving him wheat and soy (and never give cow's milk to any baby under 1). Wait until he's 2 to give him egg whites; wait until he's 3 to offer fish, shellfish, and peanut butter.

If you don't have a family history of food allergies:

  • Breastfeed. It still helps protect your child from developing a food allergy.
  • Talk with your pediatrician about when to start your baby on solid food. Introducing solids before 4 months ups the risk of food allergies. And waiting past 6 months, though previously recommended to prevent food allergies, may actually increase your baby's risk of a wheat allergy.
  • When you do start solids, introduce foods one at a time, and wait at least two to three days before starting another new food so you can pinpoint the cause of any allergic reaction.
  • Don't introduce egg whites, wheat, and cow's milk until your baby turns 1, and peanut butter and shellfish until age 2 or 3.

Common Triggers

The most common food allergy culprits are eggs, milk, peanuts, soy, wheat, tree nuts (such as pecans and walnuts), fish, and shellfish. The good news: 80 to 90 percent of kids with allergies to milk, eggs, wheat, and soy will outgrow them by age 3. Still, always check with an allergist before you reintroduce any food that's caused a problem. She'll likely do a CAP blood test—which checks your child's antibody levels for specific foods—to help decide what to do.


If your child has a reaction, you may see these symptoms within minutes of her eating even a trace amount of the offending food.

  • Rashes
  • Hives
  • Stomach pain with vomiting
  • Diarrhea
  • Difficulty breathing
  • Swelling of the mouth and throat


As soon as you suspect a food allergy—even a mild one—talk with your pediatrician. She'll probably refer you to an allergist who will give your child a skin and/or blood test to determine whether he has a true allergy and whether he may react to other foods. You may be asked to keep a food diary for a few weeks, in which you write down everything your child eats (and what you eat, if you're nursing), and any symptoms you notice. This log will help your doctor pinpoint allergy triggers and figure out a treatment plan. Another method involves avoiding a suspect food for about two weeks, and then reintroducing it at the doctor's office, where emergency care is available.

Eating with a Food Allergy

If your child is diagnosed with a food allergy, the first step is to eliminate the culprit from her diet. Shopping and meal prep may take longer, since you'll have to wade through ingredients on labels and in recipes. (To speed up the process, make it a point to learn food-label lingo). But you'll find that there are actually lots of tasty foods, in grocery and health food stores, for people with food allergies. (If you're formula-feeding your baby, talk with your pediatrician about what's the best brand for her.)

Food Allergy vs. Food Intolerance

It's easy to confuse the two, since symptoms can be similar. While an allergy involves the immune system, an intolerance does not. With a food intolerance, the body doesn't have enzymes that help digest certain compounds in foods (like the lactose in milk), so when a child eats that food, it can cause stomach pain, bloating, gas, loose stools, and occasionally, vomiting. Unlike with food allergies, these symptoms may not develop until several hours after eating the food, and they're less severe than the symptoms of an allergic reaction. Also, small amounts of a troublesome food won't necessarily cause problems.

If Your Child has an Allergic Reaction

The first allergic reaction to a particular food often happens after the second exposure to that food—and fortunately, it's usually mild to moderate, with symptoms like hives and itchiness. However, if he has trouble breathing, call 911. Otherwise:

  • Give your child a dose of a liquid antihistamine, like Benadryl.
  • Watch him closely for the next 15 to 30 minutes for serious symptoms such as difficulty breathing, swelling of the lips and tongue, wheezing, and increased drooling (a sign that airways are blocked), which require emergency help.
  • Stop giving your child that food until he sees a doctor. Symptoms can worsen the next time your child eats what he's had a reaction to.

For Emergencies

Let friends, relatives, and caregivers know about your child's food allergy so they can help keep her safe. But realize that no matter how hard you try, accidental exposures can happen. That's why it's important to make sure you and everyone else taking care of your child always has the following items:

  • Antihistamines (like liquid Benadryl) to treat a mild allergic reaction.
  • An EpiPen (injectable epinephrine), which your doctor will prescribe if your child has had a previous severe allergic reaction (such as anaphylaxis, which can close up a child's throat so she can't breathe). The epinephrine reverses the effects of the allergic reaction. (Learn how to use the EpiPen yourself, and teach it to those who care for your child as well.)
  • A cell phone (charged!), so you can call 911 in case of an extreme allergic reaction.
  • Safe snacks, so you don't get stuck with a hungry child and no reliable food options.

Additional Resources

The Food Allergy & Anaphylaxis Network 
Find more food allergy information and get free e-mail alerts about mislabeled foods. (800-929-4040)

If your child wears a MedicAlert bracelet, doctors will know his allergy history quickly in an emergency (888-633-4298)

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