Food Allergies Attack
As many as 15 million Americans suffer from food allergies – that’s about four percent of all U.S. adults and eight percent of U.S. children. Food allergies occur when the immune system reacts to specific food proteins. When even a small amount of that protein enters the body, the immune system causes the body to produce antibodies that trigger the symptoms of an allergic reaction, which can be anything from a scratchy throat to difficulty breathing.1
The Top Allergy-Producing Foods
It’s possible to be allergic to any food, but eight foods make up 90 percent of all food allergies in the United States: milk, eggs, peanuts, tree nuts, soy, wheat, fish, and shellfish.
Peanuts and Tree Nuts
An estimated .6 to 1.3 percent of the United States population suffers from a peanut allergy, making it one of the most common. Studies suggest this number tripled from 1997 to 2008, though the reasons are unclear.2 The number of Americans who report an allergy to tree nuts – such as walnuts, almonds, pistachios, or cashews – is similar, hovering between .4 and .6 percent. Allergies to all nuts tend to develop in childhood, are usually lifelong, and can be very serious (sometimes fatal). Anyone with a nut allergy should carry an epinephrine auto-injector (such as an EpiPen®) in case of a severe reaction.3
While there is no cure for nut allergies, some preliminary studies suggest it is possible to reduce the intensity of allergic reactions to peanuts using a technique called immunotherapy. Under a doctor’s close supervision, a patient with a nut allergy will be exposed to the allergen in gradually increasing amounts. One study found that 91 percent of kids between the ages of seven and fifteen with a nut allergy could safely consume the equivalent of five peanuts per day after six months of regular immunotherapy. That said, more research is still needed, and studies have not been able to demonstrate how long the protection will last without continued immunotherapy.4
Cow’s Milk, Eggs, and Soy
Allergies to cow’s milk, eggs, and soy often appear in childhood but in most cases subside with age. That said, one study found that children are taking longer to outgrow these allergies, though the majority of kids still kick them by age fifteen.5
Cow’s milk allergy is the most common one among infants and toddlers, affecting about 2.5 percent of kids under the age of three.
Egg (specifically, the protein found in egg whites) is the second most common allergen affecting young kids. Because egg whites cannot be separated completely from the yolk, people with an egg allergy should avoid eggs completely. And it’s not just food that poses a risk – some vaccines contain egg proteins, so be sure to inform health care professionals of an egg allergy.6
About .4 percent of children have an allergy to soy. But studies show this allergy is often outgrown by age three, and the majority of kids will kick the allergy before age ten. Soy is used in a lot of processed foods, so it’s best to inspect food labels carefully.7
Fish and Shellfish
More than 6.5 million Americans report allergies to fish or shellfish, two allergies that generally last for life. Even if you’ve made it through childhood without an adverse reaction to seafood, don’t assume you’re in the clear. About 60 percent of people with a shellfish allergy and 40 percent with a finned fish allergy have their first reaction as adults. An estimated .4 percent of the U.S. population reports an allergy to finned fish, while shellfish allergies are a bit more common, affecting about .6 percent of all U.S. children and 2.8 percent of adults. Allergies to finned fish and shellfish can be very severe, so people who have them should carry an emergency epinephrine auto-injector at all times.
Of the two types of shellfish, some people are allergic to one group and not the other. Crustacea – such as shrimp, crab, and lobster – typically cause more severe reactions than mollusks (for instance, clams, muscles, and scallops). If you suffer from a shellfish allergy, consult with a doctor before guessing whether the sensitivity is to only one specific group.
While it’s possible to be allergic to any sort of finned fish, salmon, tuna, and halibut cause the highest percentage of reactions. The majority of people allergic to one type of fish are allergic to others. Consult with a doctor for more specific allergy testing before trying to determine the extent of a fish allergy.8
Wheat allergies are most common among children and are typically outgrown before adulthood (and many times before the age of three). Wheat allergies can be tough to diagnose because they are often confused with conditions such as gluten intolerance or celiac disease. In the case of a wheat allergy, the body reacts with more allergy-like symptoms such as hives, itching, swelling, or trouble breathing rather than the digestive-tract issues typically associated with celiac disease.9 Depending on the severity of the reaction, a doctor or healthcare professional may prescribe an EpiPen to be carried at all times to treat anaphylactic reactions.
Why Has the Number of Food Allergies Increased?
There is no avoiding it: the number of food allergies has significantly increased over the last two decades. One 2013 study by the Centers for Disease Control found that food allergies in children increased 50 percent between 1997 and 2011. However, the reasons for this increase are still hotly debated, and scientists are still trying to figure out the causes of this steep rise.10 While we have no concrete answers, there are two main theories.
The Hygiene Hypothesis:
The hygiene hypothesis dictates that an increasingly clean environment has decreased exposure to certain types of bacteria that may have prevented food allergies in the past. Supporters of the hygiene hypothesis also believe that the frequent use of antibiotics and vaccines in Western culture have eliminated these bacteria that historically allowed us to better tolerate some food allergens. While this is a widely publicized hypothesis, more research is needed.11
Lack of Early Exposure
The second major hypothesis to explain the rise in food allergies is that kids are not exposed to allergens at a young enough age to develop tolerances.12 One study comparing children in the United Kingdom to children in Israel found that Israeli kids, 69 percent of whom were exposed to peanuts before nine months of age, had a much lower rate of peanut allergy compared to the British kids, only 10 percent of whom were exposed to peanuts as infants.13 Other research has found that children whose mothers consumed nuts during pregnancy – specifically, more than five times a month – had the lowest risk of developing an allergy to peanuts or other nuts later in childhood.14 Both studies support the idea that early exposure to potential allergens lowers the risk of developing allergies to those specific foods.15 But again, more research is needed before a definitive conclusion can be drawn.
What to Do If Symptoms Occur
Allergic reactions to foods result in one emergency room visit every three minutes – or more than 200,000 visits each year. Symptoms of an allergic reaction can range from mild itching of the throat to severe problems, including difficulty breathing. Depending on the severity of the reaction, treatment varies.
Mild and Moderate Reactions
Mild or moderate reactions to food allergens – such as itching, sneezing, hives, or rashes – can often be treated with an oral antihistamine.16 Oral antihistamines come in both pill and liquid forms. If you’re unsure what to look for, ask a doctor or pharmacist for help selecting an antihistamine.
Even if an over-the-counter drug takes care of the symptoms, don’t let the treatment end there. When experiencing a possible allergic reaction for the first time, avoid the food until you see a healthcare professional for allergy testing and diagnosis.17
The most severe type of allergic reaction is called anaphylaxis, which requires treatment within minutes to avoid potential complications, including death.18 Anaphylactic reactions to food result in 300,000emergency room visits, 2,000 hospitalizations, and 150 deaths each year. The symptoms of anaphylaxis include:
- Flushed skin or rash
- A tingling or itchy sensation in the mouth
- Swelling of the face, tongue, and/or lips
- Vomiting and/or diarrhea
- Abdominal cramps
- Coughing or wheezing
- Dizziness or lightheadedness
- Swelling of the throat and/or vocal chords
- Difficulty breathing
- Loss of consciousness
Once an anaphylactic reaction starts, a shot of epinephrine (a hormone also known as adrenaline) should be administered immediately to slow or stop the reaction.19 Anyone with a severe allergy should carry a portable epinephrine auto-injector (such as the EpiPen, Auvi-Q™, or Adrenaclick®) with him or her at all times. These auto-injectors are simple to use and can be administered quickly by the person suffering the reaction or by anyone in the vicinity at the time of the reaction. Each auto-injector comes with a set of simple instructions meant to assist in this type of situation.
Anyone with a severe allergy, especially school-aged children, should have access to an epinephrine shot at all times. About 15 percent of kids with food allergies have had a reaction at school. Make sure the child’s school has an epinephrine shot on site regardless of whether or not there is an identified allergy: 20 to 25 percent of epinephrine administrations in schools are on children whose allergy was unknown at the time of the reaction.
Once initial symptoms subside, symptoms may recur. Medical experts recommend monitoring the person who suffered the reaction for at least four hours to make sure the reaction is over.20 If symptoms return or do not improve, go to the emergency room.21
How to Prevent Exposure
The first line of defense to prevent allergic reactions is to avoid exposure to the allergen. Unfortunately, most reactions occur when people eat foods they thought were safe but accidently came into contact with the allergen during preparation. The lesson? There is no such thing as being too careful.
Accidental consumption at home can be avoided by completely eliminating the allergen or thoroughly washing any surface the allergen touches with soap and water. If cooking the allergen at home, know that some foods can release proteins as vapor or steam while being cooked, which can cause an allergic reaction when inhaled (though this is very uncommon and primarily occurs with fish allergies).22
When eating out at a restaurant, always inform food service workers of allergies, and make sure to ask that food be prepared with clean tools and hands. Casual exposure – for example, by skin-to-skin contact or smelling – is unlikely to lead to a severe allergic reaction. However, casual exposure can be more problematic for kids. For example, touching a table with a smudge of peanut butter on it can lead to a dangerous reaction if a child with a severe allergy happens to touch his or her mouth.
The Food and Drug Administration has strict labeling practices to ensure that Americans have access to safe, allergy-free foods. The eight major allergens must be declared on all packaged food labels. This includes listing any ingredients derived from those allergens [for example, “lecithin (soy)” or “flour (wheat)”].23 This disclosure may also appear on food labels in a statement after the full ingredient list, such as “Contains wheat, milk, and soy.” To help allergy sufferers avoid potential cross-contamination issues, some food manufacturers also include “May contain” statements on packaging. For example, a box of cereal with no peanut ingredients may say, “May contain peanuts” if the cereal is produced in the same factory as peanut-containing foods. These “May contain” statements are completely voluntary. That said, the FDA states that the labels do not mean that manufacturers can skip any equipment sanitation best practices meant to prevent cross-contamination.24
Food allergies are serious, and the landscape for these reactions is ever changing. While the FDA does have strict guidelines in place to keep allergens clearly noted on food labels, they continue to better manage the use of these terms by manufacturers to help consumers. Be aware of any known allergens and take care to avoid them. Read food labels carefully and always have a plan in case a reaction takes place.