Asthma and Food Allergies -- What You Should Know

by Frederic Little, M.D. Health Professional

Asthma and food allergy

In this entry, I would like to review the increase in food allergies and discuss the connection between asthma and food allergies.

Food allergies

For those of us 35 years old or older, we seem to be faced with an epidemic of food allergies. Does anyone remember "nut-free classrooms" when we were kids? Nowadays it seems that all classrooms of young kids are nut free. While to some this may seem to be a bit of hype, the proportion of kids with both food allergies, and allergies overall, is much higher (in fact over two times higher), than it was 20 years ago. So, this is not just an issue of more awareness, more vigilant parents, or "better bookkeeping."

The increased rate of allergies in children has been objectively measured in health surveys using skin-* testing and found to be truly increased. The allergies tested in these surveys, mostly to pollens and other airborne allergens, is matched with an increase in food allergies.

While nuts -- both peanuts and so-called "tree nuts" (e.g. almonds, walnuts, hazelnuts, pecans) -- are the most common food allergens, many people are allergic to certain seafoods, including shellfish and flat fish. For an individual with a severe food allergy, eating can often feel like playing Russian roulette. There are many hidden ingredients in foods and traces of foods that are not related to a particular food but rather to the equipment on which the food was made.

Food allergic reactions can be serious, with the most concerning called anaphylaxis. This is a severe allergic reaction, often to very small amounts of food allergen, that affects several systems of the body. Anaphylaxis can cause low blood pressure (which can be life threatening), hives, constriction of the mouth and throat, and wheezing. While there are excellent emergency treatments for a severe allergic reaction (a shot in the leg or arm of epinephrine -- "EpiPen
®"), about 200 to 300 individuals die every year in the United States from anaphylaxis related to foods.

Asthma and food allergy

There is a close connection between allergies and asthma. And many people with food allergy also are allergic to environmental allergens -- pollens, dust mites, mold, etc. People who have both a severe food allergy and asthma are especially at risk if they have an allergic reaction, as their asthma is likely to be triggered during a reaction.

Unlike a gradually worsening asthma flare, wheezing and difficulty breathing can come on extremely quickly during an allergic reaction -- this combination can be life-threatening. In fact, researchers have shown that the majority of people who died from an allergic reaction to food also had asthma and they died from severe wheezing leading to respiratory failure.

Anyone who has food allergy should discuss what to do and what medicines to have handy with their doctor in case they have a reaction. This is even more critical for people who have food allergy and asthma, as this can be a deadly combination.

Closing thoughts

Food allergies are definitely on the rise, and people with asthma and food allergies should carefully read food ingredients and always ask what's in the food they are eating when they are with friends or eating out. As a person with asthma and several nut allergies whose worse asthma flares have been associated with allergic reactions to nuts, I can truly say that prevention and being prepared are the keys to keeping food allergy as something to live with and not live through

Anaphylaxis & You - What You Need to Know

Frederic Little, M.D.
Meet Our Writer
Frederic Little, M.D.

Frederic Little is an Assistant Professor in the Department of Medicine at Boston University. He attends on the Allergy Consultation Service as well as the Medical Intensive Care Unit and Pulmonary Consultation Service at Boston Medical Center. He wrote for HealthCentral as a health professional for Asthma and Allergy.