Full Gastronomic Tilt

This week, May 10-16, is the 12th Annual Food Allergy Awareness Week.

What?! No recipes??  C’mon Leigh, it’s already been a month!
Yep, I know.  They’re coming.
Be patient, and read on to feed your brain.

As one who passionately enjoys food in all forms, not being able to eat something because it might kill me is an uncomfortable thought. Depending on the research being cited, an estimated 12 million Americans (including between 4 and 8% of children) have some type of food allergy. Many people associate food allergies with children, as a condition outgrown once one reaches adulthood, and for good reason: doctors and researchers around the country have noted a significant increase in children being diagnosed with food allergies over the last decade. However, adult-onset allergies are also becoming more commonplace.

Food allergies were a topic I knew painfully little about until it became a factor in some of the work that I do. Shortly thereafter, one of my close friends was suddenly diagnosed with a complex food allergy. While I consider myself a sensitive person, I shamefully admit that my initial reaction was “Oh, well she can just avoid the food and everything will be okay.” She was quick to point out that her allergy was a severe one, and that even exposure to particles of the food could cause a reaction requiring a hospital stay. This was a wake up call for me, and I realized that a total shift in my thinking was in order.

I thought I would put on my grad student hat for a bit and share some of what I have recently learned. Feel free to chime in with additional questions or insight.

What is a food allergy?

A true food allergy occurs when your immune system mistakenly identifies a specific food or a substance in food as a harmful substance. Your immune system triggers cells to release antibodies to fight the culprit food or food substance (the allergen). The next time you eat even the smallest amount of that food, the antibodies sense it and signal your immune system to release histamine, as well as other chemicals, into your bloodstream. This results in the physical manifestation of an allergic reaction, which presents as a range of symptoms ranging from mild (rashes, hives, itching, swelling) to severe (trouble breathing, wheezing, loss of consciousness, anaphylactic shock). An allergic reaction to food can take place within a few minutes to an hour. The process of eating and digesting food affects the timing and the location of a reaction. Both raw and cooked foods can cause allergic reactions. Cooking a food does not prevent it from causing an allergic reaction.

There is also a particular type of food allergy known as pollen-food allergy syndrome or oral allergy syndrome. When a person suffers from a condition like hay fever (a colloquialism for seasonal allergies - allergies to something in your environment, like pollen, grasses and/or trees) certain fresh fruits, vegetables and even nuts and spices can trigger an allergic reaction. This is called cross-reactivity.

The allergic reaction in this instance is caused by fruit and vegetable proteins which are similar enough to the allergy-causing proteins found in certain pollens, grasses or trees. As an example, if you’re allergic to ragweed, you may also react to melons or bananas; if you’re allergic to birch pollen, you may also react to apples, hazelnuts, peaches and other stone fruit.

What is the difference between an intolerance and an allergy?

More common than food allergy, a food intolerance is not caused by the immune system. The symptoms may be similar, if less severe. A common food intolerance is lactose intolerance, or when a person has difficulty digesting the milk sugar lactose. Symptoms include abdominal cramps, bloating and diarrhea. Not life-threatening, just aggravating.

Other types of food intolerance include: food poisoning, histamine toxicity, food additives (like MSG), sulfites (commonly found in red wine), gluten intolerance and psychological intolerance.

What is anaphylaxis?

In some, a food allergy can trigger a severe allergic reaction called anaphylaxis. Anaphylaxis is a systemic (as opposed to localized) allergic reaction and is dangerous for a number of reasons, including:

* Airway restriction
* Cardiac arrest
* Sudden, severe drop in blood pressure (anaphylactic shock)

Symptoms and affected systems vary widely from person to person and incident to incident. Emergency treatment is critical for anaphylaxis. Untreated, anaphylaxis can cause a coma or death. In the United States, there are approximately 30,000 episodes of food-induced anaphylaxis which occur per year, associated with 100 to 200 deaths; most deaths occur in adolescents and young adults. Food allergy is the most frequent single cause of emergency room visits for anaphylaxis.

What foods are most likely to cause an allergic reaction?

In children, six foods cause almost all food allergy reactions: Milk, egg, peanuts, wheat, soy, and tree nuts (walnuts, pecans, etc.) Children often outgrow allergies to eggs, milk and soy post-adolescence.

In adults, four foods are to blame for nearly all food allergy reactions: Peanuts, tree nuts, fish and shellfish

So, why the sharp increase in food allergy diagnoses?

This was a question to which I was eager to undercover the answer. Unfortunately, the answer is: “No one knows.” In fact, no one can say for sure if the total number of allergy cases are rising as fast as some believe. Numerous theories have been bantered about, from the impact of environmental changes to the effects of genetics, as well the “hygiene hypothesis,” which holds that children are being exposed to fewer micro-organisms and thus have weaker immune systems. A strong consensus has yet to be reached, and it is not known how much of the observed increase is due to an actual increase versus how much is due to increased diagnosis as a result of higher cultural awareness (i.e. fewer parents now assume that their kids’ severe aversions to foods are just pickiness, and doctors are more likely to consider food allergies as a possible cause of things like eczema in infants and toddlers); the best guess is a combination of the two.

The FDA requires detailed ingredient labeling, so accommodating a food allergy can’t be that hard, right?

In spite of recent legislation aimed at empowering the consumer to buy with confidence, accidental exposure remains a leading cause of allergic reactions to foods. The Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA) required new labels on packaged foods containing major food allergens (defined as milk, eggs, fish, crustacean shellfish, tree nuts, wheat, peanuts and soybeans, or any other ingredient that contains protein derived from one of these foods or food groups). Unfortunately, while this legislation was a major step in the right direction, on its own FALCPA is not enough to protect American consumers, for several reasons:

1. While manufacturers are required to label the top eight allergens in plain language, labeling for possible cross-contamination is strictly voluntary and not regulated. Much like the words “all-natural” and “pure,” terms like “allergen-free,” “nut-free,” etc. are not regulated. A company can claim that their food is “peanut-free” and list peanut flour as an ingredient without violating any labeling laws.

2. As part of the legislation, labels have to include plain-English descriptions of ingredients and possible allergens. For example, “milk” is used instead of “casein.” But the issue of “may contain” labels was not addressed. I’m sure you’ve seen them - “may contain peanuts,” “processed on shared equipment,” or “manufactured in a facility that processes peanuts or milk.” May contain labeling gets confusing quickly because it is not FDA regulated. Acting as a sort of loophole for food manufacturers, the “may contain” label is used because a small number of food products labeled as such do contain an allergen. Astonishingly, about 2 percent of food products without the “may contain” claim also contain allergens.

3. Food labels are required to list the vast majority of ingredients in any given food, with exceptions made for “spices” “natural flavoring” and the like. I find it to be generally good practice, whether you have food allergies or not, to read the labels if you are purchasing packaged food. If you have an allergy, and see one of your allergens listed, then you don’t purchase or eat the food. The problem with this seemingly straightforward approach is that a food protein can have more than one name. Examples of different names for some food ingredients appear below:

Milk proteins:

• Casein, caseinates, rennet casein
• Lactalbumin, lactalbumin phosphate, lactoglobulin, lactulose

Egg proteins:

• Albumin (also spelled albumen)
• Meringue or meringue powder
• These items also may include egg protein: artificial flavors; lecithin; macaroni; marzipan;
marshmallows; nougat, and pasta. Read the label of these products very carefully.

If you are allergic to peanuts, avoid the following ingredients:

• Artificial nuts, beer nuts, ground nuts, mixed nuts, monkey nuts, nut pieces
• Cold pressed, expelled or extruded peanut oil or arachis oil
• Mandelonas
• Peanut butter, peanut flour
• These items may include peanut protein: African, Chinese, Indonesian, Mexican, Thai and
Vietnamese dishes; baked goods; candy; chili; egg rolls; enchilada sauce; flavoring; marzipan;
nougat, and sunflower seeds.

I sourced my information from the following useful sites:

The Food Allergy and Anaphylaxis Network
Medline Plus (a service of the National Institutes of Health)
The American Academy of Allergy, Asthma and Immunology (PDF pamphlet on food allergies)
The American Academy of Allergy, Asthma and Immunology (Tips to Remember: Food Allergies)
Mayo Clinic guidelines on food allergies
Health Day article: Food Allergy Labeling Not Always Accurate
NYT article: Food Allergies Stir a Mother to Action

More interesting food allergy-related sites:

Allergic Cascade - the biology of allergic reactions
Glossary of food allergy related terms
A guide to how food labels do and don’t work

Many thanks to Rachel, for her insight and inspiration.