What are Food Allergies?
Preventing Food Allergies
Common Signs of Food Allergies
8 Facts About Food Allergies
Most and Least Allergenic Foods
Tracking Down Hidden Food Allergies: 3 Steps
Testing for Food Allergies
Food Allergies While Breastfeeding
Life-Threatening Food Allergies
Food Allergy Resource
Elimination Diet

Approximately three to seven percent of children and adults have food allergies or food intolerance. Food allergies have been called the great masqueraders because they are a hidden cause of so many problems, ranging from mere annoyances to downright disease. Food allergies tend to be underdiagnosed by physicians and overdiagnosed by everyone else. The truth about their prevalence is somewhere in between. In one study of children whose parents were convinced that their child had food allergies, only 39 percent of the allergies could be confirmed scientifically. Perhaps with no other medical problem is partnership between physician and patient more vital. The patient's role is to be a keen observer and accurate reporter. The physician's role is to take the information gathered by the patient and work out a step-by-step plan for tracking down hidden food allergies and figuring out what to do about them. Here are some facts you should know about food allergies and what to do about them.

Allergy. The term "allergy" comes from two Greek words, alos (other) and argon (action). If you are allergic to something, you have a reaction other than what you would expect. You don't expect to get hives when you eat a red tomato. That kind of a reaction would be an allergy. An allergy may manifest itself in various target organs, meaning sites where allergy signs occur. These are usually one or more of four places: the skin, the intestines, the respiratory passages, and the brain, i.e., (behavior changes).

Intolerance. The term food intolerance means that a food upsets your intestines, yet does not bother any other target organ. Food intolerances are usually due to an enzyme deficiency, (such as lactase deficiency), which causes lactose intolerance. Or, the intestines may be oversensitive to certain foods, resulting in abdominal discomfort, diarrhea, and bloating. Intolerance is usually a reaction to the protein content of a food, yet you could be intolerant to any part of the food, including sugar and/or additives.

Food hypersensitivity. Essentially means the same as "allergy." We will lump all three of the terms (allergy, intolerance, and hypersensitivity) together and simply call them food sensitivities. Practically speaking, people don't really care about definitions, they just know that certain foods bother them (or their child) more than other foods.

Here's what goes on in your body when you're hypersensitive to a food. The suspect protein is known as an allergen. When an allergen gets into your body, it comes into contact with the target organs, usually the skin or the lining of the breathing passages or intestines. When something gets into the body that it doesn't like, it mobilizes defense troops called antibodies. When the fight breaks out between these allergens and antibodies, microscopic explosions occur that release chemicals, such as histamines (hence, allergy medicines are called antihistamines), that disturb the integrity of tissues. Blood vessels dilate and produce a rash, fluid leaks out through the injured blood vessels, causing runny nose, puffy and watery eyes, or the muscles in the breathing passages go into spasms of wheezing. Even the brain can be bothered by an allergic reaction. A new field of research interest, called "brain allergy," describes the behavioral reactions of the brain when it's bothered by certain foods.

If one parent has food allergies, the risk of the children having food allergies may double; the risks are even higher if both parents are allergic. Yet, a child may have a completely different food allergy than that of the parent. If you and your spouse are passing along genes that will place your children at high risk for developing food allergies, the following prevention regimen can lower the child's risk by around fifty percent.

• Prevent allergies prenatally. Some studies suggest that mothers who are allergic to certain foods, especially dairy products, can lessen the chances of their infants being allergic to that food by limiting the child's exposure prenatally. Avoid bingeing on common allergens during pregnancy and while breastfeeding.
• Breastfeed your baby as long as possible. The longer you breastfeed, the less chance your child has of developing allergic diseases, such as eczema and asthma. Breastmilk is rich in an immunoglobulin called secretory IGA, which acts as a protective paint, coating the intestines and keeping food allergens out of the bloodstream. Breastmilk keeps the intestinal lining healthy and better able to break down proteins into individual amino acids. The amino acids themselves are not likely to cause allergies when they get into the bloodstream. Intestines that are damaged due to infection or inflamed by foreign milk or formula may allow whole protein molecules to seep through, setting up an allergic reaction in the bloodstream. To further decrease the risk of developing food allergies, it would be wise for a breastfeeding mother to keep the most allergenic foods out of her diet until her baby is at least one year of age.
• Delay introduction of solid foods. Mature intestines are better able to screen out potential allergens and keep them from entering the bloodstream. If you feed your infant solid foods (especially those containing protein, such as wheat, soy, and dairy) before the intestinal lining is mature, food allergens can seep into the bloodstream, causing baby to build up antibodies to those allergens and later become allergic to those foods. When you do start solids, introduce the least allergic (lowest protein) foods first, such as fruits, vegetables, and rice. Wait until at least eighteen months before introducing potentially-allergic foods, such as egg whites, tomatoes, shellfish, and peanut butter . Make citrus fruits the last fruits you introduce. Also, if you're formula-feeding, discuss with your doctor the use of hypoallergenic formulas (a partial whey hydrolyzed formula), such as Alimentum or Nutramigen. Avoid soy formulas . Also, delay introducing cow's milk products until at least a year of age. By twelve months of age, your child's intestines are mature enough to screen out most of the food allergens. (See Starting Solid Foods)
• Variety, variety, variety. The less children eat of one particular food, the less likely they will become allergic to it, since most food allergies are dose related. Encourage your children to eat a variety of foods. Continuing to bombard the body with the same food risks turning on the food- antibody response. Rotation diets make good sense for every eater, and especially for the allergic person.

Be a pure parent. During the early years, make your child's diet as fresh and as additive-free as possible. The fewer cans, boxes, and packages you open, the less likely your child is to be exposed to allergens. Be especially vigilant to keep food colorings out of your child's tummy, namely yellow dye #5 and red and blue dyes.

While individual signs and symptoms of food allergy are as unique as fingerprints, usually at least one of the four common target organs are involved: the respiratory passages, skin, intestines, and brain. While it's relatively easy to spot a rash, a wheeze, a bout of diarrhea, or abdominal cramps and attribute the problem to food allergy, brain changes are more subjective. In our experience, some children can experience behavioral changes due to food sensitivity without showing any other signs or symptoms, but most food allergies attack more than one target organ. Don't be too quick to pin the rap for your child's school failure on food allergy, at least not without symptoms beyond the academic ones.

Here are some facts you should know about the subtleties of food allergy:

1. Food allergy symptoms vary in severity. While one mother may have to rush a wheezing child to the nearest emergency room within minutes after he eats a peanutbutter sandwich, another child may develop only a nuisance-like rash around the mouth.

2. It may take a few minutes, a few hours, or a few days for a food to cause a reaction. Monday's chocolate bar may be the cause of Tuesday's rash. Food allergies are often known as the "eat now, pay later" phenomenon.

3. Food allergies are often dose related. A teaspoon of peanut butter may not be a problem, but a couple tablespoons on a big sandwich can trigger wheezing. Some people do just fine with one glass of milk, but may get bloated after drinking three glasses. Eating shellfish every day could make you break out in an all-over body rash, yet having a few shrimp every four days may not be a problem. This is the rationale for the "rotation diet" in which you eat related food groups every four days.

4. Even though it's possible to be allergic to just about any food, over 90 percent of food allergies, especially in young children, are caused by seven foods:

• dairy products
• soy
• shellfish
• wheat
• tree nuts
• peanuts
• egg whites

5. If you're allergic to one food in a food group, you have a greater chance of being allergic to other foods, or all the foods in that group. If you're allergic to peanuts (which is a legume and not a nut), you may be able to eat almonds, but not other foods in the legume family.

6. Don't be surprised if you actually crave the food you're allergic to. When you go on an elimination diet , your body may go through withdrawal symptoms, triggering cravings for the very food that is not good for it. Sometimes the wisdom of the body breaks down. This food-craving paradox is especially true in children who are hypersensitive to sugar . When the blood sugar rises and then falls, children crave the food that will send their blood sugar skyrocketing.

7. Food allergies should not interfere with a child's growth. Few foods are absolutely essential for growth. A child who is allergic to one food can certainly get the same nutrition in many other foods.

8. Allergy symptoms change with age. The good news is that most children outgrow their food allergies by three years of age. The tomato- allergic toddler may become the preschooler who can safely indulge in ketchup. Children tend to outgrow their sensitivity to milk and soy products; other food allergies, such as nuts and shell fish, tend to persist.

The incidence of food allergies may be on the rise because more people are eating processed foods containing preservatives and additives. It's no wonder that the body rebels against all the foreign substances added to food in factories.

Most-Allergenic Foods

• berries
• buckwheat
• chocolate
• cinnamon
• citrus fruits
• coconut
• corn
• dairy products
• egg whites
• mustard
• nuts
• peas
• peanut butter
• pork
• shellfish
• soy
• sugar
• tomatoes
• wheat
• yeast

Least-Allergenic Foods

• apples
• apricots
• asparagus
• avocados
• barley
• beets
• broccoli
• carrots
• cauliflower
• chicken
• cranberries
• dates
• grapes
• honey
• lamb
• lettuce
• mangoes
• oats
• papayas
• peaches
• pears
• poi
• raisins
• rice
• rye
• safflower oil
• salmon
• squash
• sunflower oil
• sweet potatoes
• turkey
• veal

Potentially allergenic foods may be listed under another name in packaged foods. The most common are:

• wheat flour: durum semolina, farina
• egg white: albumin
• dairy products: Casein, sodium caseinate.
  TIP: Food without ANY diary products will say "Parve" on the package. You will usually find these foods in the kosher section.

Careful label reading will help you discover what you are eating:

• Cocoa mixes, creamed foods, gravies, and some sauces contain milk.
• Noodles and pasta contain wheat and sometimes eggs.
• Canned soups may contain wheat and dairy fillers.
• Most breads contain wheat and dairy products.
• Margarine usually contains whey.
• Hot dogs, cold cuts, and "nondairy" desserts contain sodium caseinate.

For persons who keep kosher , the word "pareve" on a label means the food does not contain milk or meat. However, recent studies on persons who suffered severe allergic reactions to pareve—labeled foods revealed milk residues.

Here's a three-step method for uncovering what food could be bothering you or your child.

STEP 1: KEEP A FOOD RECORD
Over a four-day period record everything that gets eaten. If you are keeping records for yourself, be sure to include snacks or meals you eat at work or at restaurants. If you're keeping a food record of what your child eats, do it during a four-day period when your child is home all day so you know exactly what he eats. Don't make an issue of your child's food choices during this time or he may sneak (because he craves) the very foods he's sensitive to. Enlist your child's cooperation so that together you can keep an accurate record. Also, keep track of any symptoms that you feel may be caused by food allergies.

Suspected Allergenic Food	Associated Symptoms	Results after Elimination	Notes
Milk Strawberries Peanuts	Facial rash Diarrhea watery eyes cough waking up three times a night	Rash dried up Cough lessened frequency of diarrhea lessened awakened once	Couldn't tolerate milk, but yogurt and cheese okay

STEP 2: TRY AN ELIMINATION DIET
On your list, circle the foods that you most suspect, paying particular attention to the nasty nine:

• dairy products
• soy
• egg whites
• wheat
• peanuts
• tree nuts
• citrus fruits
• shellfish
• food additives

If you have no hunch what you or your child may be allergic to, seek medical help from your doctor or an allergist. Start your elimination diet at a time when there are no outside influences that make the diet impossible to follow, such as during holidays, birthdays, vacations, parties at work, etc. Once you have picked out the most plausible offenders (with or without your doctor's allergy-testing help), eliminate these for at least ten days (preferably two weeks) and keep track of any reactions. Avoid multiple-ingredient foods during this time, since these may contain multiple potential allergens, making it difficult to isolate the single offender. Focus on objective signs and symptoms; changes in mood or behavior are harder to evaluate.

NUTRITIP: Play Food Detective Enlist the help of your child to uncover the hidden food allergies. Make a game out of it. Explain to your child that there's something in some food that causes her to have a rash and a sore tummy, "Let's see if we can figure out what it is by playing food detective." Tell your child that "the rash gives us a clue, so we need to write down all the foods you eat, so we can figure out what causes the rash."

STEP 3: CHALLENGE YOUR FINDINGS
It's humanly impossible to be perfectly objective in pinpointing offending foods and what quantities of them cause reactions. Because you don't want to eliminate nutritious foods from you or your child's diet without good reason, it's a good idea to test your findings by reintroducing suspicious foods one at a time, seeing if the concerning signs and symptoms reappear. If they do, that food goes on your no-no list, at least for a few months. Later you can find out whether or not your allergy is dose-related by reintroducing the food, beginning with a small amount once every four days and then increasing both the amount you eat and how often you eat it until your most annoying signs reappear. This threshold effect is especially characteristic of dairy allergies . Some people can't even drink one glass of milk a day, but they can tolerate a cup of yogurt every other day.

NUTRITIP: Beware of Combination Allergies Allergens may appear in the most unlikely places, so get used to reading the ingredient list. A candy bar, for example, may contain corn, dairy, gluten, soy, colorings and additives – all of which are potential food allergens.

THE QUICK-DETECTION METHOD FOR ZEROING IN ON FOOD ALLERGIES
Use this method if you are a well-disciplined adult. It is more difficult to use successfully on a child.

1. Eliminate the possible suspect foods, beginning with the nasty nine, for a period of at least a week or ten days. During this time, eat only the least allergenic foods, such as: fresh fruits (except berries and citrus), avocados, rice, barley, millet, poultry, and lamb. All the foods, if possible, should be organic and free of additives, dyes, and colorings.

2. Reintroduce one new food each week to see if symptoms reappear.

How much time, energy, and expense you are willing to spend on tracking down food allergies depends upon how much they bother you or your child, and whether your symptoms are getting better or worse. The good news is that food allergies are one medical problem where you can truly say that children will "grow out of it." Most food allergies in children either become less severe or entirely disappear as they get older. Of course, if the child is miserable and is making everyone else miserable, too, you may not want to wait for him to grow older to do something about them.

NUTRITIP: Sweetener Allergy Once upon a time we physicians were all taught that the body can only be allergic to proteins. But once again, others' observations are at odds with scientists. Many wise parents report that their infant or child goes berserk after high doses of sweeteners, such as corn syrup. Even the purists among allergists are beginning to believe in the concept of brain allergy, meaning that the chemicals a person eats can have a profound effect on biochemistry -- thinking, feeling, and behaving. Corn syrup is a common sweetener in processed foods, baby formulas, and sodas. The fact that corn syrup has become so prevalent in the American diet may account for an increasing number of allergies to it. As one mother who successfully tracked down her infant's gassiness, diarrhea, night-waking and fussy behavior to corn syrup wrote us, "I feel that there is a corn syrup conspiracy going on in our country."

At present there are no medical tests for food allergies that are more accurate than the detective work of a parent who is a keen observer and accurate recorder. In most cases, a carefully done elimination diet will uncover what the allergy is to. Your doctor or allergist can help by performing one or both of the following tests:

• Skin test. A skin test is helpful in uncovering hidden food allergies, but it has a high incidence of false positives, meaning the skin test is likely to show that you or your child is allergic to a food when really you are not. A negative skin test (i.e., your child does not react to a certain food allergen injected in his skin) is a reliable indication that you are unlikely to be allergic to that food.
• Blood test. This test, called a RAST (Radio-Allergo-Sorbent Test), measures the antibodies in your bloodstream to certain food allergens. Unlike the skin test, a RAST test has a high degree of false negatives, meaning it does not detect food allergies that your child really has. A positive RAST test is a reliable indicator that you are likely to be allergic to that food. If a certain food, say peanuts, show up positive on a RAST test, that means you are more likely than not to be allergic to peanuts. If a skin test and a RAST test agree, you can give the results even more weight. But keep in mind that neither a skin test nor blood test is as reliable as your own observations, and they are certainly more costly. Testing may be most helpful when the results of an elimination diet are confusing.

Research shows mixed results about whether maternal food restrictions during breastfeeding will lessen the risk of food allergies in babies. In fact, a study presented at the 1996 meeting of the American Academy of Allergy, Asthma, and Immunology showed a surprising result: The children of breastfeeding mothers who withheld allergenic foods from their diet later showed an increase in food allergies.

At present, there is some scientific basis for believing that cow's-milk products in a mother's diet can cause colicky symptoms in a baby, and therefore it would be wise for a breastfeeding mother with a family history of cow's-milk allergies to withhold dairy products from her diet, at least during the first year. It would be wise for a breastfeeding mother to seek nutritional advice from a doctor or nutritionist before going on a restrictive diet; otherwise she (and perhaps her baby) could run the risk of nutritional deficiency.

Some food allergies, especially to nuts and shellfish, can be life- threatening in very sensitive people. The windpipe may go into spasms or the cardiovascular system may go into shock (called anaphylaxis) within minutes after eating a particular food. If you or your child has had a serious reaction to a food, even severe hives or wheezing, discuss with your doctor or allergist the possibility of keeping an adrenaline-filled syringe (such as a bee-sting kit) with you for emergencies. This can be a life-saver if you are not within minutes of an emergency room. To prepare yourself for using the real medicine, use a practice kit to learn what to do and how to do it. If you or your child accidentally eats a food that has caused a severe reaction before, go immediately to the nearest emergency room and sit in the waiting room for a couple hours, just as a precaution. If the reaction is not severe enough to merit emergency treatment, you can go back home. Adults and children who are very allergic should wear a medical alert bracelet.

Food Allergy Network,
10400 Eaton Place, Suite 107, Fairfax, VA 22030-2208 (703-691-3179 or www.foodallergy.org). Ask for their booklet Learning to Live with Food Allergies or their bimonthly newsletter, The Food Allergy News.

Tracking Down Hidden Food Allergy, by William G. Crook, M.D. (Professional Books, 1980)

Resource for testing for food allergies:
Immuno Laboratories, 1620 W. Oakland Park Blvd., Fort Lauderdale, FL 33311 (800-231-9197 or www.immunolabs.com)