The Facts About Food Allergies

Asking questions and being informed can help you cope

Medically Reviewed by Matthew Hoffman, MD on March 20, 2008
4 min read

When I was young, I sometimes claimed an "allergy" to foods I did not like so I would not seem impolite if served one of my least favorite foods. These days, some people use the word "allergy" to describe any discomfort associated with food.

Real food allergies are no joke. Many Americans suffer from them and don't even know it. The reactions can range from mild irritations, such as hives, swelling, and gastrointestinal discomfort, to life-threatening situations.

Children are most likely to suffer from allergies, but adults have them, too. The primary food allergy culprits are milk, eggs, peanuts, tree nuts, wheat, soybeans, fish, and shellfish. Yet any food can cause a reaction if it contains ingredients that are not tolerated.

A food allergy triggers an immune response, which attacks the lining of the intestines and causes discomfort. People who are allergic to gluten (a protein found in wheat and other grains) often mistake their allergy symptoms, such as gas, diarrhea, cramping, and weight loss, for any number of gastrointestinal conditions.

It's not uncommon for food allergies to be misdiagnosed. If you suspect you have allergies, see your doctor. Most allergies can be diagnosed with skin tests, but you can have a negative skin test and still be allergic to a certain food. Accurately determining food allergies usually requires a medical evaluation and trial elimination diets.

Not all problems with food result from an allergy. Sulphites, lactose, and monosodium glutamate (MSG) are examples of food substances to which many people are intolerant or hypersensitive. This is not the same as an allergy but can cause similar symptoms. Allergies trigger immune responses, but the body's immune system is not responsible for the symptoms of food intolerance.

Foods containing sulphites say so on their labels, but it takes careful scrutiny to make sure there's no lactose or MSG in a food. Sulphites are not permitted in fresh foods but can be contained in processed potatoes, wine, frozen avocados, dried fruits, and bottled lemon juice.

The "cure" for food allergies -- eliminate the offending foods -- is not as easy as it sounds. Some foods are obvious, but others require careful reading of the ingredient list. For some, you may need to contact the manufacturer.

Understanding label terminology is key to avoiding food allergens. Milk may be referred to by its components "whey" or "casein," and eggs can appear on a label as "albumin." Avoiding breads and cereals is relatively easy for those with a gluten allergy. But traces of wheat can be found in some lunch meats, soy sauce, soups, malt vinegar -- even jelly beans. These minute amounts are not always listed on the ingredient panel.

On Jan. 1, 2006, the Food Allergen Labeling and Consumer Protection Act went into effect. This law requires manufacturers to identify wheat and other grains to which people may be sensitive on product labels. Potentially allergenic substances must be identified by commonly known names -- so no longer will you need to know that lactalbumin contains milk.

Yet even with the new law, declaring every ingredient can be a daunting task. Minute amounts of allergenic substances can be used to make spices, and some manufacturers who use them may not realize they contain an offending ingredient. Further, sometimes the entire list of ingredients won't fit on a particular food label.

When food companies are unsure of potential ingredients, their labels often indicate that the product "may contain" a certain ingredient.

Companies change formulas, and it is a constant challenge to make sure your foods are free of allergens. For example, simply changing lecithin to soy lecithin makes the product unacceptable for anyone with a soybean allergy.

Consumers who are extremely sensitive to a particular item should make it a practice to contact manufacturers to make sure the offending ingredient is not contained in products they buy.

Most anyone with food allergies can tell you about their favorite brands that are free of offending allergens. Specialty food manufacturers understand what their clients need.

Meals prepared away from home are not routinely labeled with ingredients. The most frequent reactions to foods occur in a restaurant, or as a result of food carried out from a restaurant.

When eating out, keep it simple and avoid anything that is unknown. Ask questions, and consider printing up a card with a list of your allergies for your waiter to share with the chef.

If you're not certain about an item, it's best to err on the side of caution and avoid that food. Also keep in mind that highly sensitive people can have reactions due to cross-contamination from a piece of equipment. For example, using the same fryer for french fries and seafood could bring a reaction for someone highly allergic to seafood.

Here are some tips to avoid allergic reactions:

  • Avoid salad bars or self-serve buffets.
  • Stick to prepackaged foods that are clearly labeled.
  • Find support groups, and swap recipes and names of favorite allergen-free brands.
  • Let all your friends and family know which foods they should avoid in your presence.
  • If you're unsure whether you have an allergy or hypersensitivity, withdraw the food for two weeks, than reintroduce it to see if you have a reaction.