For some, the word allergy conjures up images or memories of runny noses and itchy eyes, for others it may be digestive issues, and inflamed skin. Regardless of how they show up, allergies are surprisingly common with an estimated 30-50% of the population having them. Besides the personal impact of allergy symptoms and on quality of life, allergies have a huge societal economic cost with lost productivity and medication costs. For most, allergies are a life-long with the onset often beginning between 8 to 12 years of age, although for some, like Celiac disease, can develop at any time throughout the life cycle.
Being clear on language is important when talking about any topic but not the least of which when discussing food allergies and intolerances. According to Health Canada’s website, the topic can be categorized by the following:
Food sensitivity – an adverse reaction to a food that other people can eat safely. This reaction can be due to food allergies, food intolerances, and chemical reactions. In this sense, food sensitivity is the umbrella term for all food and food-based ingredients that can elicit a reaction.
Food intolerance – traditionally food sensitivity has not been seen as a type of allergy per se because it’s largely believed that food intolerance does not involve the immune system unlike food allergies or chemical sensitivities do where very small amounts of a food can cause a reaction. With food intolerances, a larger amount of a given food has to be eaten to produce symptoms. A well-known example is lactose intolerance where, without sufficient amounts of the enzyme lactase, a person will experience abdominal pain and bloating, diarrhea and flatulence. Most however can tolerate smaller amounts of lactose especially if eaten with other foods; 1/3 cup of milk with lunch or dinner for example.
Although there isn’t an immediate allergic response like there is with a classic food allergy, food intolerances should be considered to be a milder form of allergy since studies have shown them to involve other types of antibody involvement like IgM and IgG antibodies. Because IgG antibodies are produced at a slower rate [hours to days after exposure] and not to the degree that IgE antibodies do, food intolerances have not historically been considered an allergy.
Food allergies – this is the classic immune response where there are a lot of IgE antibodies produced to a specific food proteins which, at its worst, can result in anaphylaxis. Here food proteins are mistakenly seen by the immune system as being harmful like pathogens are. Upon repeated exposure, the immune system response by producing large amounts of histamine which can cause reactions in the respiratory system, gastrointestinal tract, skin and cardiovascular systems as well.
The top 10 food allergies include
- seafood (fish, crustaceans, and shellfish)
- tree nuts
If you’ve experienced, or think you may have, a food intolerance, food allergy or chemical sensitivity, consult your family physician, a nutritionist or dietitian who can help to assess and determine the extent of any of these concerns.