We live in a reactive society. Up to 6% of children and 4% of adults are living with a diagnosed food allergy; many more are living with other forms of food hypersensitivity and intolerance. While reactions to food are very real and can be the underlying cause for conditions such as migraines, eczema and irritable bowel syndrome, the term allergy is often incorrectly used to describe another food reaction. So what exactly is food allergy and how does it differ from hypersensitivity and intolerance?
Food Allergy
Food allergy is an ImmunoglobulinE or IgE immune-cellmediated reaction to a protein in certain foods; all other non-IgE reactions to food are not considered true allergy. In Canada priority allergens include peanuts, tree nuts, shellfish, egg, milk, wheat, sesame and soy. Reactions range from mild to severe; anaphylaxis is the most severe form of allergy and involves a life-threatening reaction to, most commonly, peanuts, tree nuts, seafood, eggs or milk. Oral allergy syndrome is a unique form of allergy where pollen allergy causes cross reactions to certain foods such as apples, almonds, cherries and pears to name a few. Cooking foods associated with oral allergy syndrome may reduce reactivity of oral allergy syndrome. This is not the case with standard food allergy, where eating even tiny amounts of the offending foods either raw or cooked will cause a reaction, so allergens must be strictly avoided.
Food Hypersensitivity
Although food hypersensitivity has an immune component, it differs from food allergy in that it does not involve IgE immune cells. Celiac disease is a specific type of food hypersensitivity that involves an auto-immune response to the gluten proteins in wheat, barley, rye and most oats. Other hypersensitivities exist, including those to soy, milk or cereals. Hypersensitivities can lead to enterocolitis, inflammation of the intestinal tract and colon, and are often diagnosed in infancy due to profuse gastrointestinal symptoms.
Food Intolerance
Whether to lactose, sulphite or fructose, food intolerances do not involve the immune system at all. For instance, lactose intolerance is the body’s inability to tolerate lactose (milk sugars) in varying amounts. This stems from a reduction or complete lack of lactase, the enzyme responsible for breaking down lactose in the gut. Other intolerances include sucrose, histamine and food dyes. Varying amounts of the offending substances may be tolerated and total avoidance is not always necessary.
The Bottom Line
Most symptoms of food reactions are quite general and are shared among a host of conditions such as environmental allergy, infection, metabolic disorders or other disease processes. Never self-diagnose an allergy or other food reaction. This could lead to missing a serious underlying cause for your symptoms. When true allergy and other causes for symptoms such as celiac disease or sulphite sensitivity have been ruled out, work with your dietitian or other licensed health professional to discover which foods may be causing you discomfort and learn how to eat a balanced diet without them.
Hungry for knowledge? Email nutrition@choicesmarkets.com.
