Between 50% and 90% of all severe allergic reactions to foods are caused by only eight foods. The most common food allergies are: milk, eggs, peanuts, tree nuts, soy, wheat, fish and shellfish. Each of these "big eight" food allergies has its own unique challenges.
The most common food allergies for adults differ from the most common food allergies for children. Many children outgrow their allergies to milk, eggs, or wheat in early childhood. Adults may develop new allergies later in life.
The good news is that these ingredients should be clearly labeled with an allergy warning on all packaged foods made in the United States. For example, a food that contains hydrolyzed vegetable protein derived from soy is required to have a statement that says "Allergy warning: contains soy" on the ingredient label.
The bad news is that not all foods are manufactured in the United States, and products such as shampoo or lotion may contain these allergens but are not required to list them separately. You still need to be a label detective.
The most common food allergies, in order of frequency, are:
- Frequency: Cow's milk is the most common food allergy in American children. 2.5 percent of children have a cow's milk allergy. It is not a major allergen for adults.
- Outlook: Up to 80 percent of children will outgrow their allergy to dairy products by the age of six.
- Where allergens hide: Deli meats, "non-dairy" creamer, skin and hair care products, canned tuna, and some craft paints.
- Other sensitivities: A milk allergy is an immune response to milk proteins, which is different from lactose intolerance, in which your body lacks the enzyme needed to digest milk sugars. Children with milk allergy must avoid all dairy products, including those that are lactose-free.
- Dairy Allergy Basics
- Foods to Avoid on a Dairy-Free Diet
- Frequency: 1.4 percent of children and 0.6 percent of adults are allergic to peanuts. There is some evidence that the rate of peanut allergies is increasing among children in the United States.
- Outlook: Peanut allergies are often very severe, with higher rates of anaphylactic reactions than milk, eggs, or wheat. They also tend to be lifelong allergies. Only 20 percent of children will outgrow their peanut allergy by the age of six.
- Where allergens hide: Peanut butter is sometimes used as a thickener for chili or "glue" for egg rolls. Peanut oil may be found in some skin care products. A common source for accidental exposure in children is bird seed.
- Other sensitivities: People with peanut allergies have a higher rate of tree nut allergies than the general population, even though peanuts are legumes (beans), not nuts.
- Peanut Allergy Basics
- Foods to Avoid on a Peanut-Free Diet
- Surprising Non-Food Peanut Products
- Raising a Peanut-Free Kid
- Frequency: Shellfish allergy is the most common food allergy for adults. Two percent of American adults have a shellfish allergy. 0.1 percent of children have a shellfish allergy.
- Outlook: Shellfish and fish are allergies that often develop later in life, unlike many other allergies. They tend to be severe, life long allergies.
- Where allergens hide: Vitamins, pet food, fertilizer, fish food. People with shellfish allergies may react if they breathe in airborne particles from sizzling or boiling food.
- Other sensitivities: People may be allergic to crustaceans (lobsters, shrimp, crawfish) or mollusks (clams, oysters, mussels) or both.
- Shellfish Allergy Basics
- Foods to Avoid on a Shellfish-Free Diet
- Frequency: 1.1 percent of children and 0.5 percent of adults have a tree nut allergy. There is some evidence that the rate of tree nut allergies is increasing in the United States.
- Outlook: Tree nuts tend to be life long allergies, and have higher rates of anaphylactic reactions than milk, eggs, or wheat. Only 9 percent of children will outgrow their tree nut allergy by age six.
- Where allergens hide: There are so many names for tree nuts that it can be difficult to determine if a product contains nuts. Nut shells are sometimes used to stuff beanbag kick toys, such as hacky sacks.
- Other sensitivities: Tree nuts are actually very different from each other, and it is possible to be allergic to one nut, for example almonds, but not others. It is also possible to be allergic to multiple nuts as well as peanuts.
- Tree Nut Allergy Basics
- Nut Ingredients - List of Tree Nuts and Nut Ingredients
- Frequency: Eggs are the second most common food allergy for children. 1.5 percent of children are allergic to hen's eggs. Eggs are not a major allergens for adults.
- Outlook: Up to 80 percent of children will outgrow their allergy to eggs by the age of six.
- Where allergens hide: Many immunizations are created by growing viruses in hen's eggs. Ask your child's doctor about which immunizations are safe for him. Other medications, such as anesthetics, may also contain eggs. "Egg substitutes" such as Egg Beaters contain eggs.
- Other sensitivities: It is possible to be allergic to just egg white, just egg yolk, or both. It is probably not possible to completely separate a white and a yolk from an egg at home.
- Egg Allergy Basics
- Foods to Avoid on an Egg-Free Diet
- Frequency: 0.4 percent of adults and 0.1 percent of children have a fish allergy. It is possible to be allergic to just one species of fish and not others.
- Outlook: Fish allergies often develop in adulthood. They tend to be severe, life long allergies.
- Where allergens hide: Restaurants may fry fish in the same oil as other foods. Kosher gelatin (found in kosher pudding or marshmallows) is made from fish bones.
- Other sensitivities: Fish that is less than fresh can develop high levels of natural histamine. When eaten, it can produce symptoms similar to food allergies, but called scromboid poisoning. If you have symptoms such as swelling of your mouth or throat, difficulty breathing, nausea or vomiting after eating fish, call 911. Taking a piece of the fish with you to the hospital will help doctors determine the cause of your symptoms.
- Fish Allergy Basics
- Foods to Avoid on a Fish-Free Diet
- Frequency: 0.4 percent of American children are allergic to soy. It is not a major allergen for adults.
- Outlook: About 50 percent of children will outgrow their soy allergy by the age of seven.
- Where allergens hide: Soy is a very common ingredient in packaged foods, hair and skin products, and even gasoline. Beanbag toss toys are often stuffed with soybeans. Some organic stuffed animals are made from soy fibers. Vitamin E is usually derived from soy, and there may not be a soy allergy warning on the ingredient label.
- Other sensitivities: Because of the risk of developing a soy allergy, babies with milk allergy or milk protein intolerance should not be fed soy-based formula.
- Soy Allergy Overview
- Foods to Avoid on a Soy-Free Diet
- Surprising Non-Food Soybean Products
- Frequency: 0.4 percent of American children are allergic to wheat.
- Outlook: About 80 percent of them will outgrow their wheat allergy by age six.
- Where allergens hide: Soy sauce, beer, deli meats, imitation crab meat. Spelt and kamut contain the same proteins as wheat, and should not be eaten by people with wheat allergies. Non-food items such as glue, Play-Doh, lotions, and shampoos.
- Other sensitivities: Wheat allergy is different from Celiac disease, which is an autoimmune disorder in which you can not digest wheat or other gluten-containing grains, such as barley or rye. Wheat allergies can be difficult to figure out, since sometimes allergy symptoms only appear in combination with exercise (exercise-induced anaphylaxis).
- Wheat Allergy Basics
- Foods to Avoid on a Wheat-Free Diet
- Foods to Avoid on a Gluten-Free Diet
American Academy of Allergy, Asthma and Immunology. â€œHealth Statistics.â€ Accessed June 20, 2010. http://www.aaaai.org/media/statistics/allergy-statistics.asp#foodallergy
Sicherer SH, Sampson HA. Food allergy. J Allergy Clin Immunol 2006;117:S470-5.
Branum AM, Lukacs SL. Food allergy among children in the United States. Pediatrics 2009;124:1549-55.
Chafen JJ, et al. Diagnosing and managing common food allergies: a systematic review. JAMA. 2010 May 12;303(18):1848-56.
Scott H. Sicherer, MD, et al. US prevalence of self-reported peanut, tree nut, and sesame allergy: 11-year follow-up. J Allergy Clin Immunol. Volume 125, Issue 6, Pages 1322-1326 (June 2010)
Sicherer SH, Mun-oz-Furlong A, Sampson HA. Prevalence of seafood allergy in the United States determined by a random telephone survey. J Allergy Clin Immunol 2004;114:159-65.