Health & Lifestyle

The difference between a food allergy and a food intolerance (or food hypersensitivity)

The difference between a food allergy and a food intolerance (or food hypersensitivity)

Ask anyone born before 1970 if they know what a ‘food intolerance’ is and I bet around 80% of them would say there’s no such thing, it’s an urban myth or it’s an excuse for a fussy eater. And do you know what, around a year ago, I would have probably said the same thing.

Do you know why? Because I didn’t recognise that the uncomfortable symptoms I had 99% of the time weren’t actually ‘normal’. I just put up with them, not realising that they were actually having a detrimental impact on my body both physically and mentally. The lack of energy, consistent bloating rendering half of my wardrobe redundant and stomach cramps all took their toll on my mental well being. The symptoms of a food intolerance or food hypersensitivity may not be as severe as those associated with a food allergy, but the long term impact of them due to them being more difficult to diagnose, can be really quite debilitating.

Food intolerance symptoms

Over the past few months, I’ve been doing a lot of research into the science behind food intolerance and I aim to share it with you in hopefully more of a digestible (no pun intended) and easy to understand manner.

First things first, what is the difference between a food allergy and a food intolerance?

What is a food allergy?

Fortunately the definition of a food allergy is quite clear and involves the immune system, although there are two different types.

The most common type of food allergy involves the production of Immunoglobulin E (IgE) antibodies. In short, when you eat something containing the allergen, your body’s immune system goes into ‘fight’ mode, producing IgE antibodies to attack the perceived threat. As a result of this, you get unpleasant side effects (as you do when your body is attacking a virus) which can manifest themselves through symptoms such as gut problems, rashes, itching, swelling and difficulty breathing.

Food allergy vs food intolerance

Although the symptoms of a food allergy sound pretty scary, the positive is that they are relatively easy to diagnose through testing for the presence of IgE in the blood. As such, the symptoms associated with food allergies can be avoided by removing the allergen from your diet. Fortunately, it is now a legal requirement for food manufacturers to list all common allergens in products making them easier to avoid.

The second type of food allergy is a lot harder to diagnose because, although it is also caused by the immune system, it is not caused by the production of a specific antibody. This is known as a non-IgE food allergy, a true allergic reaction, and can also cause severe symptoms including vomiting, inflammation of the gut, pain, diarrhoea and constipation. Food allergies can also cause skin problems such as eczema – something which you might not always associate with what you are putting in your body. This type of food allergy is more common in children and can only be diagnosed through specialist help.

According to charity allergy UK, food allergies are quite rare, affecting around 2% of adults and up to 8% of children in the UK (although considering the second type of food allergy is rarely diagnosed, I have to wonder how accurate these figures are).

What is a food intolerance?

The definition of a food intolerance is a lot less clear cut than a food allergy and they are much harder to diagnose. Symptoms of a food intolerance aren’t as severe as those associated with a food allergy but, from my experience, the culmination of these symptoms over time can make life difficult. These symptoms can include bloating, stomach pain, skin problems such as psoriasis, constipation, diarrhoea and lack of energy which, over time, can lead to mental health problems.

Food allergen vs food sensitivity

Identifying the type of food you have an intolerance to can be extremely difficult, particularly as it’s not uncommon to have an intolerance to multiple food types and often, the proteins in these foods are present in some unlikely places. For example, who knew that the proteins in dairy can be present in the flavourings used in crisps?! In addition, symptoms relating to a food intolerance can take up to 72 hours to present themselves so if you’re anything like me, you’ll have eaten plenty during that time!

The general advice is to keep a strict food diary while monitoring your symptoms to see if you can spot any trends. In all honesty, once I finally admitted to myself that my symptoms weren’t normal, I wanted a quicker fix (plus I didn’t trust myself to keep a food diary). That’s why I decided to take a YorkTest. This involved sending a blood sample off to be analysed for the presence of Immunoglobulin G (IgG) antibodies. IgG antibodies are the first to be made to fight an infection. Depending on the level of IgG antibodies in your blood when presented with different food types suggests whether you may or may not have an intolerance to it. The more IgG antibodies, the more intolerant you are to the food type being tested.

Food allergen vs food sensitivity

It has to be noted that this isn’t an exact science (hence why intolerances are much harder to diagnose than food allergies which tend to present symptoms within a couple of hours) and as such, these tests aren’t available through the NHS. I have to admit, once I cut out dairy, I felt an improvement from around two weeks however after around three months of continuing with this strict diet, I started to once again suffer with severe bloating. So I’m slightly back to the drawing board. I’m not going to do another IgG test but I am going to experiment through keeping a food diary and cutting out gluten over the next month or so to see if I can reduce or eliminate these symptoms. Dairy is definitely still an issue for me, so I’m not going to reintroduce this just yet. I want to get to the point where I don’t suffer with the bloating for a sustained period of time before trying to reintroduce my trigger foods.

If you think you might be suffering from a food allergy or intolerance, I hope this goes some way to helping you to take the next step.


Related Articles

The difference between dairy intolerance and lactose intolerance You often hear the term ‘lactose-free’ bandied around; from adverts showing lactose intolerant hedgehogs in supermarkets to rugged men shouting libert...
Turning my intolerance into a positive I have just got back from a lovely weekend in Wensleydale near Leyburn with Chris and his family. We stayed at a gorgeous cottage called Theaked Stone...
Grilled cajun turkey steak with roasted aubergine Following our trip to Tuscany, we were both ready for something light but tasty for dinner. This dish struck exactly the right cord (and, as always, w...


Leave a Reply

Your email address will not be published. Required fields are marked *