Food Allergies

This information is has been researched from a variety of resources believed to be trustworthy and based on scientific research. It is provided only as a resource and is not intended as medical advice or endorsement. If you believe that you have a food allergy or intolerance, it is very important to discuss your concerns with a medical professional.



Food Allergies

What Are Allergies?

Allergies come in many forms, the most common cause of an allergy being particles in the air such as with hay fever.

Allergies are the body’s reaction to a specific protein or, in the case of sulfites, a specific chemical.  The body mistakenly believes the protein or chemical to be an allergen and musters the body’s immune system to create antibodies to protect against that allergen.

A recent study shows that 1 in 13 Canadians have a serious food allergy.  This equates to over 7.6% of Canadians and does not include Celiac Disease or food intolerances. Given the similarities between Canadians and Americans, comparisons can be easily drawn regarding the prevalance of food allergies in America.

Minor Allergic Response

When the body is first exposed to a specific protein and identifies it as an allergen, antibodies are created and they attach themselves to mast cells.  The next time the person is exposed to that allergen, the proteins of that allergen become attached to the antibodies.  The mast cells then explode, causing histamines to be released into the body and the symptoms begin.

Symptoms of a minor allergic response can include:

  • runny, itchy, stuffy nose;
  • sneezing;
  • watery, itchy eyes;
  • fatigue;
  • headache

These are very similar to cold symptoms.  People with asthma may find that their attacks are triggered by allergens.

Major Allergic Response/Anaphylaxis

Like a minor allergic response, the body goes through the same process of creating antibodies and attaching themselves to mast cells, exploding and releasing histamine when the body is exposed to the specific allergen again.  However, with a major allergic response (also known as anaphylaxis), the explosion of histamine overwhelms the body and can cause death.

Symptoms of a major allergic response can include one or some of the following:

  • wheezing or difficulty breathing;
  • tingling in the mouth;
  • swollen lips, throat, tongue or face;
  • hives, skin rash, itching, feeling of warmth;
  • significant swelling around the site of an insect sting;
  • abdominal cramps, nausea, vomiting;
  • faintness or  loss of consciousness;
  • anxiety/feeling of impending doom

The Danger of Perceiving a Food Allergy as Minor

When a person has a minor allergic reaction or just one anaphylactic symptom, they often perceive that they have a minor food allergy.  The issue with this is that the body creates more antibodies every time exposure to that specific allergen occurs.  What does that mean?

It means that a reaction this time could show minor symptoms but the next time the body is exposed to that food, the histamine explosion could be enough to prompt a full anaphylactic response.  If a person believes that their food allergy is minor, they are completely unprepared for this major response, putting their life at risk.

Unfortunately, no one can accurately predict the nature of the next response.  It might be minor but the risk is very real for anaphylaxis.  This is why it is very important to treat a food allergy seriously and see your medical professional about how to manage it.

What Are the Top Food Allergens?

Canada

US

UK/EU

peanuts

peanuts

peanuts

tree nuts

tree nuts

tree nuts

soy

soy

soy

dairy

dairy

dairy

eggs

eggs

eggs

wheat

wheat

wheat

fish

fish

fish

shellfish

shellfish

shellfish

sesame

 

sesame

mustard

 

mustard

sulphites

 

sulphites

 

 

celery

 

 

lupin

In other areas of the world, common foods to certain cultures may become a top food allergen such as buckwheat (used in soba noodles) in Japan or sesame in the Middle East.

Oral Allergy Syndrome

Not a true food allergy yet mimicking some of the same symptoms in the mouth and throat, Oral Allergy Syndrome is a specific reaction to proteins in certain fruits, vegetables and nuts.  Those with Oral Allergy Syndrome may react with raw foods such as apples but not react when those foods are cooked, such as with applesauce.

An oral allergy reaction is often preceded by hay fever symptoms and is often worse during pollen season.  While rare, Oral Allergy Syndrome reactions can be severe, including anaphylaxis.

For more information and to see the foods and environmental allergies often associated with this syndrome, please see the Canadian Food Inspection Agency’s report on Oral Allergy Syndrome.

What Causes Allergies?

No one knows for certain what causes allergies.  What we do know is that all allergies and asthma are on the rise.  For some reason, third world countries do not see the same immune system issues that developed countries do.  The prevalent reasoning for this is what is referred to as Hygiene Theory.

Hygiene Theory

This theory is based on the hypothesis that we have become too clean in our daily living.  In the past, it is believed that our immune systems developed by exposure to dirt, animals, and bacteria.  Now that we live in a more hygienic world, the premise is that our immune systems have not fully developed and are turning on what should be innocuous substances (food) as if they were a mortal threat. 

Because anaphylaxis is the response of the immune system known as an IgE, response, this theory bears some weight.  The IgE response in humans is normally associated with the body’s fight against parasites.  Yet in the modern, urban world, we rarely encounter parasites like our ancestors did, which may be causing the IgE to respond to certain foods instead.

Treatment for Food Allergies

The only known and accepted treatment for food allergies at this time is complete avoidance of the specified food.  If accidentally exposed to that food, your doctor may prescribe the use of antihistamines, steroids and/or the use of an emergency injection of epinephrine.

Many researchers from around the world have been working on treatments for food allergies in highly controlled settings with some success.  While promising, these require more study and should never be attempted on your own:

Oral Immunotherapy (OIT)

Oral immunotherapy has been successfully practiced in several clinical studies.  Unfortunately, it has also been practiced unsuccessfully in less controlled settings such as at home and by some naturopaths, one of who was sued for the death of a client in England.

Essentially, oral immunotherapy is giving controlled doses of the food allergen protein by mouth starting with miniscule amounts and gradually increasing as the immune system builds tolerance.  Properly done, in the right controlled setting including at Mount Sinai, approximately 50 to 75% of the patients in the studies show a tolerance to the allergic food.

Sublingual Immunotherapy (SLIT)

This treatment is very similar to Oral Immunotherapy but rather than eating small amounts of the allergen, the food allergen is dissolved in a solution that is then placed under the tongue.  So far, this treatment hasn’t been as effective as Oral Immunotherapy but further studies are under way.

Chinese Herbal Therapy (FAHF-2)

This Chinese herbal therapy may prevent anaphylactic reactions to multiple food allergens.  It was successful enough in its Phase 1 study that further research was funded to move it to Phase 2 in humans specifically for patients who are allergic to peanut, tree nuts, fish, shellfish, and sesame.

Other studies and methods showing promise in addressing food allergies include research at Northwestern University Feinberg School of Medicine where the researchers managed to successfully turn off life-threatening reactions in peanut-allergic mice.