I have a lot of people come to me and state that they are allergic to this food and that food, when in fact they do not have a food allergy, it’s simply a food intolerance. The term 'food allergy' is often misused because many people don’t know the difference between an allergy and an intolerance.
Food allergies are quite serious and usually life-long. Although, some kids grow out of allergies, many will have to live with their food allergy for life, especially if it begins in adulthood.
On the other hand, food intolerance may be curable, depending on the cause. I bold that because it’s important. The cause is important. For me, the cause of my multiple food intolerances were due to gut health. I fixed my gut health and I cured my food intolerances, which, at my worst, included gluten (non-celiac), casein, nuts, all fruit, most vegetables (except root vegies), most grains (except rice) and legumes.
So what’s the difference between a food allergy and a food intolerance?
A food allergy involves the immune system, whereas a food intolerance involves the digestive system (except for sulphite and benzoate reactions). A food intolerance can cause a wide range of symptoms, such as bloating, gas, stomach pain, diarrhoea, irritable bowel syndrome, hives, rashes and headaches. Food intolerances take longer to manifest, and reactions can happen days after ingesting the food. However, food allergies cause a rapid reaction and can sometimes be deadly.
Food Allergies – Immune Mediated
IgE mediated, e.g. oral allergy syndrome, acute urticaria
Non-IgE mediated, e.g. coeliac disease
Mixed IgE and non-IgE mediated, e.g. eosinophilic esophagitis
Cell mediated, e.g. contact dermatitis
Food Intolerance – Non-Immune Mediated
Metabolic – this may be cause by an enzyme deficiency or carbohydrate malabsorption, for example;
Lactose intolerance
Fructose intolerance
Polyols intolerance
Toxic – such as food poisoning, for example;
Scombroid fish toxin
Pharmacologic – This is a chemical sensitivity or reaction to food components, for example;
Caffeine
Salicylates
Amines
MSG
Other/Undefined – This can be a reaction to artificial preservatives. It has been shown that this can be a trigger for asthma and anaphylaxis, for example;
Sulphites
Benzoates
How Do You Diagnose a Food Intolerance?
Food intolerance can be difficult to diagnose. Particularly since symptoms often appear 24 to 48 hours after ingesting the offending food. Another factor which makes diagnosing food intolerance difficult is dose dependency. Many people with food intolerance will experience more, or less severe symptoms depending on how much they eat. Food intolerance is often dose dependent.
Diagnosis of a food intolerance should be done alongside your doctor and dietician if possible; involving clinical history, responses to testing and treatment, identifying triggers, and the elimination of other conditions that may be causing symptoms.
Be aware of unorthodox testing which can be quite misleading. These “tests” for food allergies and intolerance are expensive and have no credible evidence. They can even lead to misleading results and dangerous treatments. Some of these include, Vega testing, kinesiology, allergy elimination, cytotoxic food testing, iridology, pulse testing, hair analysis and IgG food antibody testing. These tests often play on your desperation. I tried a number of these methods when I was very sick and desperate for answers. I wasted A LOT of money!
I know from experience that doctors often don’t know much about nutrition (there are some that do). So working with your GP as well as a nutritionist or dietitian is the best course of action.