What's the difference between allergies & food intolerances?

Do you know the difference between a food allergy and a food intolerance?

Last Updated: 29th December 2022 · Written by Donna Mastriani

A food allergy and a food intolerance are often thrown around in the same conversation and are thought to be the same thing when this couldn’t be further from the truth. An allergy is an entirely different condition to an intolerance and we’re here to clarify the difference for you. As well as being two different conditions, there are a lot of ‘untruths’ lying around regarding each term such as ‘an allergy can be cured if the food is removed for a period of time’ or ‘an allergy can be created by regular consumption of a food’. 

What is a food allergy?

A food allergy, when occurring, creates an immune reaction within the body. This is usually caused by the protein of an allergen entering the bloodstream. This tends to happen more often at a younger age as the lining of the gut isn’t yet fully developed. When you are exposed to the allergen, whether you have ingested, inhaled or touched the item, an IgE immune response is released as the body now sees the allergen as a threat. This release histamine and symptoms that can occur immediately or up to a couple of hours later.

Symptoms of an allergy can be;

Symptoms are completely individual and can differ from person to person, however, in the worst-case scenario, anaphylactic shock can occur in which an EpiPen needs to be administered as well as seeking urgent medical attention. It is important that you know what to do in a situation where someone is suffering an allergic reaction as it has the potential of being life-threatening. If diagnosed with an allergy through an allergy test or an experience with a reaction, you need to do all you can to constantly avoid these items. 

What is a food intolerance?

A food intolerance, such as lactose intolerance, occurs when an individual’s gut lacks the correct digestive enzymes to break down the foods. In this case, we are going to look at immune-mediated intolerances which is a reaction to IgG antibodies. There are four types of IgG antibodies – IgG₁, IgG₂, IgG₃ and IgG₄. IgG₁ is a first responder to a reaction, however, if a reaction continues to happen to a food item because we are continually exposed to an allergen, we begin to produce IgG₄ antibodies. IgG₂ and IgG₃ antibodies are not produced in response to a food item which is why at Lifelab Testing, we find IgGthe most relevant antibody for testing food intolerances

Symptoms to a food intolerance can occur up to 72 hours after the food item has been consumed. Symptoms include;

Bloating and cramps.

• Flatulence.

• Changes in bowel movements.


• Headaches.

• Fogginess.

Symptoms of an intolerance may only occur if you have eaten a large amount of the food. We can reduce symptoms of an intolerance by adjusting our diet to remove all the trigger items and then reintroducing the items after 6-8 weeks of not having consumed them. This is known as an elimination diet. 

How can you discover your allergies and intolerances?

The answer is simple, a Lifelab Testing kit. Having one of our at-home blood testing kits delivered straight to your door means that you can begin your journey to health from the comfort of your own home. A small blood sample could change your life and relieve you of your symptoms when tested in our laboratory. From as little as £74.99, you can order one of our fantastic tests and discover whether you are suffering from a food allergy or food intolerance.

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