Food Allergy Testing versus Food Intolerance Testing or Food Sensitivity Testing in Markham 

Food sensitivities, allergies and intolerances are quite common in infants, children and adults and have been implicated in a wide range of symptoms affecting virtually every system of the body.  The incidence of food reactions, atopic conditions and asthma has increased dramatically in the past two generations.

How Do Food Allergies or Intolerances Occur?

The digestive system is meant to break down food particles to a molecular level before allowing them to be absorbed through the intestines into the bloodstream.  Inadequate or incomplete digestion of food and an inflamed intestinal lining allow larger food molecules to pass into the bloodstream, where they are perceived by the immune as “foreign invaders” (antigens).  The immune system makes antibodies to bind to these food antigens, initiating an inflammatory response that is the source of many of the symptoms of adverse food reactions.  Any factor that decreases the gut’s ability to be selective about the size of particles that pass into the bloodstream could contribute to the increased incidence of food allergies and asthma occurring in the population.

Some of these factors include:

  • Deficiencies of stomach acid or digestive enzymes
  • Use of antibiotics or antacids
  • Earlier discontinuation of breastfeeding
  • Early introduction of infant formula
  • Imbalanced intestinal microflora
  • A less diverse average diet
  • Increased intake of processed foods containing various hidden food antigens
  • And genetic manipulation of foods leading to cross-reactivity within the immune system

What’s the Difference between a Food Allergy and a Food Intolerance or Sensitivity?

Food allergy involves the IgE antibody type, which cause mast cells to release histamine and trigger a process that causes airway closure, throat and tongue swelling, urticaria (hives) and possibly life-threatening anaphylaxis.  The most common IgE food allergy is the peanut, affecting about 1% of children.  Allergists typically screen for this type of allergy using skin prick testing. Individuals with this type of food allergy must typically avoid all exposure to the food they are allergic to and carry an EpiPen in case they are inadvertently exposed and experience an anaphylactic reaction.

Food sensitivities or intolerances are actually delayed type food allergies, governed by IgG antibodies, which are implicated in an estimated 80% of all adverse food reactions.  Food sensitivities can manifest with milder and non-specific symptoms, such as eczema, ear infections, headaches and migraines, diarrhea, constipation, concentration and learning difficulties, hyperactivity, poor sleep, irritability or low mood, itchy eyes and nose, sinus congestion, low energy and more.  As with IgE antibodies, IgGs can cause mast cells to release histamine, thus, hives/urticaria can occur with delayed food allergies.  IgG antibodies can also cause increased intestinal permeability, leading to conditions such as irritable bowel disease and IgA deficiency.

Food Intolerance/Sensitivity Testing in Markham

If your symptoms suggest an IgG delayed food allergy, Dr. Camille Nghiem-Phu, ND will guide you in an elimination diet to identify foods that you are sensitive to, or will order a blood test to measure the production of IgG antibodies to a panel of 100-500 foods.

Other testing that may be indicated includes “comprehensive digestive stool analysis” (internal link to “Testing & Therapies” webpage), intestinal permeability testing, assessment of adrenal gland function and testing of fecal secretory IgA levels.

Once reactive foods are identified and eliminated from the diet, the next steps often involve healing the gut, restoring optimal digestive function, developing a healthy balance of intestinal microflora (probiotic bacteria) and decreasing inflammation.

Clinically, we observe that many uncomfortable symptoms can be alleviated or eliminated with the removal of reactive foods from the diet.  If you have any questions about whether your symptoms may be related to a food sensitivity or allergy, contact Dr. Camille Nghiem-Phu, ND in Markham.