Managing the uncertainties and complexities of food allergies

For people living with food allergies, certain foods can cause life-threatening allergic reactions.

Your Immune System and Food Allergies

Normally, your immune system keeps you healthy by identifying and attacking pathogens. If you have food allergies, your immune system misreads the proteins in some foods as threats. The eight most common foods associated with food allergies are peanut, tree nuts, egg, milk, soy, wheat, fish and shellfish.

When you develop a food allergy, your body becomes sensitized to the proteins, or allergens, in one or more of these foods and makes specific Immunoglobulin E (IgE) antibodies to them. This often happens very early in life, but it can also occur in adulthood.

Then, if the IgE antibodies circulating in your blood detect an allergen you have ingested, or perhaps even just touched, they signal for an “attack.” The elements of the attack, primarily the massive release of histamine, can cause life-threatening anaphylaxis. Essentially, your immune system’s overreaction brings on symptoms — such as hives, swelling, vomiting, abdominal pain, wheezing, breathlessness or lowered blood pressure — that can, at their most severe, fatally restrict your breathing and blood circulation.

Food allergies are a significant and growing health problem in the United States, Europe and throughout the developed world. Aimmune is focused on developing desensitization products for common food allergies to potentially reduce the chance of a severe reaction following accidental exposure.

The Uncertainties of Food Allergies

Scientists have not yet determined why some people develop food allergies, but research points to a combination of genetic and environmental factors. Some allergies — to peanuts, tree nuts and shellfish — are typically lifelong; others — including egg and milk — are often outgrown by adolescence.

While skin or blood tests may identify or confirm a food allergy, no available tests can tell you with certainty how severe your potential allergic reaction might be. Even the extent of a previous allergic reaction cannot predict the severity of a future reaction.

There are no approved medical therapies to treat or cure food allergies. Upon diagnosis (which usually occurs following a first reaction), patients are told to avoid the food allergen and given a prescription for an epinephrine auto-injector, to be carried at all times in case of anaphylaxis resulting from accidental exposure.

Epinephrine relieves the symptoms of anaphylaxis by increasing the heart rate, constricting blood vessels to increase blood pressure, and relaxing muscles in the lungs to improve breathing. In order to work, however, epinephrine must be used quickly enough, administered in the correct location for the right amount of time, and have been stored within the proper temperature range.

Accidental exposure to trace amounts of food allergens from cross contact can trigger severe allergic reactions. People with peanut allergies can be sensitive to the amount of peanut protein found in a fraction of a peanut kernel.

Avoiding Food Allergens

Avoiding food allergens means knowing all of the ingredients, preparation techniques and manufacturing processes for any food to be ingested — whether at home or in a restaurant, school cafeteria, or social setting. It means careful reading of food labels, care in the storage and preparation of foods, awareness of product recalls for mislabeling or contamination, and even avoidance of cuisines where some food allergens are known to be common.

Parents often try to prevent accidental exposure to food allergens by limiting their children’s participation in social activities. They may avoid eating outside the home and even choose to home school their children. Common activities such as attending a sporting event, traveling by airplane or visiting public spaces can become difficult or stressful for food-allergic children and their families.

Numerous studies have shown that the stress of vigilantly avoiding any food allergens and the anxiety around fear of a potentially fatal accidental exposure can substantially diminish the quality of life of patients and their families.

Growing Prevalence and Costs of Food Allergies

If you have food allergies, you are far from alone. Approximately 15 million people in the United States and 17 million people in Europe have food allergies, and the numbers are growing. Estimates of the prevalence of peanut allergy, for example, in children in the United States from 1997 to 2008 show an increase at a constant annual growth rate of 10 percent, and experts believe prevalence has continued to rise since 2008.

Allergic reactions to food cause as many as 200,000 visits to U.S. emergency rooms each year. According to the Global Emergency Medicine Academy, the total economic burden of children’s food allergies on U.S. families is approximately $24.8 billion a year, with $4.3 billion attributed to direct medical expenses.