What is the difference between a Food Allergy or Food Intolerance?

AMUK Healthy Living Blog


What is the difference between a Food Allergy and Food Intolerance?

Author : Hazel Econs

Many of us have reactions to food or other substances. These can range from mild to severe, even life-threatening in some cases. What many people refer to as an allergy is actually an intolerance. So how can we know if it is a food allergy or a food intolerance?

A true food allergy usually causes an immediate reaction, within 30 minutes to two hours. This reaction can be rashes, hives, wheezing, vomiting, swelling of the tongue and/or lips or in severe cases anaphlyactic shock. An allergy is very straightforward to identify with standard skin prick tests or blood tests.

Food intolerance is more common, not life threatening and the reactions are less severe although often distressing. Reactions can occur hours or even days after a certain food has been eaten. Symptoms caused by an intolerance can be rhinitis, asthma, eczema, itching, nausea, stomach cramps, bloating, wind, palpitations and many others. In fact food intolerance is responsible for many modern-day conditions and ill-health. There are no 100% accurate blood tests to identify food intolerances, the most accurate means is by "Elimination & Challenge" (see below) although some blood tests can give useful indicators if the dietary method is too difficult to adhere to.

The most common culprits are usually common foods. Although we fill our shopping trolley with a huge variety of foods if you actually study the packaging you will see that we are frequently eating the same ingredients but in a variety of forms. For instance, we will have grains in our cereals, our bread, croissant or wrap and pasta, also in the biscuits and cakes let alone wheat in many tinned, packaged and convenience foods. The same is true with dairies, these are eaten in a variety of disguises, hence, both grains and diaries are amongst the most commonly identified foods we are intolerant too. However, it is unusual to find a person intolerant to just one food.

So how can I find out if I have a food intolerance?

The first thing is to identify the culprit(s). This can be done by Elimination and Challenge, which means avoiding common allergenic foods for a couple of weeks, seeing a clearance of your symptoms and then reintroducing those avoided foods in a specific manner to identify the problem foods. If this is not possible due to life-style or other reasons there are food intolerance tests which give some useful guidelines although not as accurate as the dietary method.

Once the food triggers have been identified and have been avoided for 6-8 weeks or more, ones tolerance improves and these foods can again be used sporadically without the same ill effects. However, if they are eaten frequently they can cause the same symptoms. A minority of patients with extensive food reactions will always remain sensitive and require a treatment we at Allergy Medical UK offer called desensitisation to improve their tolerance to these foods.

Dr. Econs' philosophy is to identify and treat the cause not just the symptom. Read more on the Food Intolerance page under Conditions.


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