Food Allergies and Intolerance

Diagnosis

Focus on Food Allergy
In newborns and older infants who are allergic to the protein in cow's-milk-based infant formulas, the signs of food allergy will include diarrhea, vomiting, and a failure to grow properly. Your child may also bleed from his intestinal tract and be colicky. Switching to soy formula doesn't always remedy the situation, since many babies who are sensitive to cow's milk protein are also allergic to the protein in soy-based formulas and other soy products. If your child exhibits any of the symptoms mentioned above in "Anatomy of an Allergy," talk with your pediatrician immediately about the best course of action. Your baby may need a hydrosolate formula such as Nutramigen, Pregestimil, or Alimentum, or an amino acid infant formula such as Neocate or Neocate One+ brand.

As your child matures and you begin offering solid foods between four and six months of age, you may suspect certain foods are troublesome for your child. To get to the bottom of food allergies, keep a detailed log of what and how much your child eats, document the symptoms produced by each food, and how long the symptoms take to develop. If your child is cared for by someone other than yourself, have her track all the same particulars, too. Include vitamin and mineral supplements your child takes on the list. Don't rely on your memory to record what your child consumes. Write it down as soon as he's finished eating or drinking. Save labels from processed foods since they could contain ingredients that trigger food allergy.

Keeping a food diary is a step in the right direction, but don't try to manage food allergies on your own. Food allergy diagnosis requires a detailed medical history; physical exam; elimination diets that include avoiding the suspected foods; and, possibly, tests to rule out other conditions. Bring your child and his food log to a doctor who has intensive training in allergy and immunology for a full evaluation. Board-certified physicians who are allergy experts are reliable health professionals.

Diagnosing Food Allergy
Don't be too quick to diagnose a food allergy in your child, and don't let others be, either. Make sure that your board-certified physician conducts more than one of the following tests before confirming food allergy.

• Medical history
• Skin prick test
• Blood test
• Elimination diet
• Food challenge

Beware of the following tests; allergy experts say they have little, if any, scientific merit:

• Cytoxic blood test
• Sublingual provocation
• Intradermal provocation
• Food immune complex assay

Managing Food Allergy
There's only one way to manage food allergy and that's avoidance. Once you know which food triggers an immune response in you or your child, steer clear of it. Some children are so sensitive to allergens that getting a whiff of an offending food, or kissing someone eating a food with the offending allergen, can be potentially fatal. For instance, something as simple as sniffing the steam created by cooking fish can cause a reaction in fish-allergic people. That's why it's a good idea to avoid keeping foods that trigger allergy in the house, even if you have other children who can eat these products without consequence.

Keep It Healthy
There's a problem with avoiding foods with known allergens, however. In eliminating foods, you must amend your child's diet to make it adequate to fuel his rapid growth. Getting rid of milk because of an allergy means your child's calcium and vitamin D consumption will drop off to the point of jeopardizing bone development.

It becomes particularly difficult to manage your child's diet when she is allergic to more than one thing. Working with a registered dietitian (R.D.) can help, especially when your doctor recommends elimination diets and food challenges. An R.D. helps you to carry out the food restrictions your child must follow, while developing an eating plan that is tailored to your child's dietary needs. Find a registered dietitian in your area by contacting the American Dietetic Association. The organization offers a free, nationwide referral service.

Read Labels
Carefully reading food labels is critical for avoiding allergens. Depending on your child's allergy or allergies, there are dozens of offending ingredients you must avoid. The Food Allergy Network provides excellent label-reading resources. Still, food labels may sport unfamiliar ingredients; may not fully explain all ingredients; and manufacturers may change ingredients without warning, so don't take food labels for granted. One troubling labeling loophole: Manufacturers may list natural flavorings as an ingredient without spelling out their specific ingredients. Genetically modified foods pose a slight risk to highly allergenic individuals since the FDA doesn't require labels to state that foods include genetically modified ingredients. Some genetically modified foods may contain allergenic proteins from other foods that are not among the major allergens.

Before feeding processed foods with questionable ingredients to your child, call the company to clarify exactly what the product contains. When there is any doubt that a food is unsafe for any reason, don't buy it.