Adverse food reactions are a very common, often unrecognized cause of ill health. It is important to know the differences between the two main types of food reactions to bring light to what’s going on in your body (and your child’s!)
Firstly, there are two types of antibodies (immune cells) that are commonly produced in response to foods; they are IgE (immunoglobulin E) and IgG. IgE reactions are immediate and are associated with full blown food allergies – these are the reactions most people associate with food allergies. These foods need to be avoided because they create life threatening allergies. On the other hand, IgG reactions develop hours to days after a food and are often termed food sensitivities or food intolerances. The symptoms they create are a lot more subtle.
Summary of Types of Food Reactions
Antibody |
Reaction time |
Common Symptoms |
Common triggers |
IgE |
Immediate |
Life threatening: breathing difficulties, hives, itchy eyes |
Peanuts, inhalants (e.g. dust, pollens) |
IgG |
Hours à 5 days |
More subtle conditions: digestive disorders, skin conditions, weight gain, headaches, low energy (see below) |
Dairy, gluten, sugar, caffeine, alcohol, soy, nuts, citrus, bananas |
The bottom line is that IgE reactions are easier to spot than IgG ones. Since they are immediate you can usually boil the threat down to a couple of items. Since IgG reactions typically take days to develop they are infinitely more difficult to determine. This is the reason why most people don’t realize they have food sensitivities!
Not noticing something doesn’t mean that it’s not immensly important. These IgG food sensitivities are truly clouding the picture of health as they are triggering mild systemic inflammation leading to symptoms throughout the body. Below are just a few symptoms that are related to these reactions – do you or your child have any of these?
Symptoms and diseases commonly associated with food sensitivities (Pizzorno 2006).
System |
Symptoms and diseases |
Gastrointestinal |
Canker sores, celiac disease, chronic diarrhea, duodenal ulcer, gastritis, irritable colon, malabsorption, ulcerative colitis, vomiting |
Genitourinary |
Bed-wetting, chronic bladder infections, nephrosis |
Immune |
Chronic infections, frequent ear infections |
Mental/emotional |
Anxiety, depression, hyperactivity, inability to concentrate, insomnia, irritability, mental confusion, personality change, seizures |
Musculoskeletal |
Bursitis, joint pain, low back pain |
Respiratory |
Asthma, chronic bronchitis, wheezing |
Skin |
Acne, eczema, hives, itching, rash |
Miscellaneous |
Arrhythmia, edema, fainting, fatigue, headache, hypoglycemia, itchy nose or throat, migraines, sinusitis |
Since many people answer ‘yes’ to having some complaints above, the next step is to take action. There are 2 main ways to uncover IgG food sensitivities.
- Easy, expensive route: A simple finger-prick blood test. Many labs now offer a comprehensive food panel done through a blood sample. Naturopathic Doctors offer this testing done in office. Cost is usually $220+.
- Harder, inexpensive route: Hypoallergenic diet. Simply remove all common allergens (listed above) for a minimum of 2 weeks. This way you can feel how your body responds to a very clean diet. Then, you challenge your body by introducing foods one at a time and playing close attention to overall health. To complete this properly it is recommended to utilize the guidance of a Naturopathic Doctor.
After you determine your sensitivities it is best to avoid them for a period of 2-3 months to allow your digestive tract time to heal. Stay positive, these IgG reactions are not always permanent! Your body can heal if you give it time. Please note as well that other factors play into why you have these food sensitivities: digestive enzymes and healthy gut flora are just a couple. The first step is to avoid the allergen, the second step is to promote healing (another shameless plug: Naturopathic Doctors can expidite the healing process).
With children, this is a lot easier if they are breasfed and you have not yet introduced foods. You simply to the ‘challenge’ part of the diet. Introducing one food every 2-3 days and looking for any changes in behaviour/skin/digestion will enable you to decifer if your child is having food reactions.
Best of luck in taking the first step to health – uncovering your food sensitivities!
Yours in health,
Sarah Oulahen HBHSc, ND
416.901.2000