The statement "I’m allergic to milk" is used quite often in normal conversation; however, true milk allergies in adults are not common. Instead of a milk allergy, a person making this comment is likely to be lactose intolerant. This confusion between food allergies and food intolerance is a frequent misconception; yet there are clear differences between the two. Food allergies involve an immune response, while food intolerances do not. Only about two to four percent of adults and six to eight percent of children under the age of three have true food allergies. Others reacting to foods most likely have food intolerance.
What is a food allergy?
A food allergy involves an abnormal immune response to a protein in a food. Over 170 foods have been documented as causing food allergies. Yet the eight major food allergens—cow’s milk, eggs, fish, crustaceans, peanuts, soybeans, tree nuts and wheat—account for over 90 percent of allergic reactions. After an initial exposure to the food allergen, the body assumes that the food is a harmful substance; thus antibodies to the food are created. Second and subsequent exposures cause the body to release chemicals into the blood stream that cause adverse reactions.
Reactions to food allergens range from mild to severe. Symptoms can occur within minutes to hours in an immediate reaction, while delayed reactions may not appear for 24 hours or more. Symptoms can affect the GI tract (nausea, vomiting, diarrhea, and cramping), skin (rashes, hives, and eczema), and the cardiovascular system.
Life-threatening allergic reactions, known as anaphylaxis, occur rapidly and involve several body parts. Anaphylaxis symptoms can range from mild to severe and include itching, hives, swelling of the throat, difficulty breathing, hypotension, unconsciousness, and even death. The Food Allergy and Anaphylaxis Network (FAAN) estimates that between 150 and 200 people die annually from food-related anaphylaxis; therefore, immediate medical treatment is needed in the event that a person with a life-threatening allergy is exposed to the food allergen.
Do I have a food allergy?
If you suspect you have a food allergy, seek a board-certified allergist for diagnosis. A variety of methods such as a food diary, elimination diet, or a skin or blood test may be used by an allergist to safely evaluate whether you have a true food allergy.
Food Allergy Management
Management of food allergies starts simply by not consuming food containing the allergen. In some circumstances the allergen may not be apparent, such as peanuts in Pad Thai, or anchovies and/or sardines in Worcestershire sauce. Because allergens can be difficult to identify, individuals with food allergies must be well aware of what they are eating. In restaurants, individuals should explain their allergies thoroughly to restaurant staff, and ask them to check with the chef if they don’t know what ingredients are in a dish. At home and at the grocery store, individuals must pay attention to food labels—manufacturers of packaged foods are now required, by the Food Allergen Labeling and Consumer Protection Act (FALCPA), to list the eight major food allergens in plain English.
What is food intolerance?
A food intolerance is any form of food sensitivity or abnormal reaction that does not involve the immune system; consequently, symptoms are less severe and generally are not life threatening. There are three accepted types of food intolerances—anaphylactoid, metabolic and idiosyncratic reactions. Anaphylactoid reactions result from the ingestion of a substance that causes the release of histamine, such as an abnormal reaction to strawberries. Metabolic reactions arise when a food or component of a food cannot be metabolized normally. Lactose intolerance, caused by deficiencies of the enzyme lactase, is the most common example of a metabolic reaction. Idiosyncratic reactions, like sulfite-induced asthma, occur via unknown mechanisms.
Symptoms of food intolerances typically involve the gastrointestinal tract and include nausea, bloating, gas, cramps, vomiting, and diarrhea. Other reactions can occur such as headaches, irritability or nervousness. Symptoms arise from the body’s inability to properly digest the food, as in lactose intolerance, or the food itself irritating the digestive system.
Do I have food intolerance?
Since symptoms of food intolerance are similar to the flu and other common ailments, food intolerances can be difficult to identify. If food intolerance is suspected, assessment with trial and error can be used to determine the cause of the adverse reaction.
Food Intolerance Management
Unlike a true food allergy where the food must be avoided, individuals with food intolerance can ingest small amounts of the afflicting food. Reactions are usually related to frequency and amount of the food ingested; thus, small amounts are not likely to cause a significant reaction. Individuals with food intolerance can also choose to manage less severe symptoms instead of reducing the amount of food ingested.
What do I need to know about food allergies and intolerance?
If you have a food allergy, avoid the food. There is more flexibility with food intolerances—you can choose to eat small amounts only, or manage your symptoms. In either case, you should always be aware of what is in the foods you eat—whether from a grocer, restaurant, or your own kitchen. Awareness is the key to management.
| Spotlight on Gluten: Celiac disease is sometimes considered a food allergy because it is the result of an adverse immune response to gluten, a protein found in wheat, barley and certain other grains. As such, individuals with Celiac Disease must follow a strict diet, which includes avoiding all foods containing gluten. Unlike some childhood food allergies, which are sometimes outgrown, Celiac Disease stays with you through your lifetime. The most common age for diagnosis is around 40, and most patients have had at least 10 years of symptoms before diagnosis. For more information go to: Other sources for information on food allergies: |
