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Food Intolerance 101


What is food intolerance?

If you’re new to food intolerance testing, I’m sure you’re eager to find out all about food sensitivities. After all, approximately 45% of the UK population suffer from a food intolerance – that’s nearly half of the population! The good news is that you don’t have to be a science whizz to understand information on food intolerance or how this plays an effect on the body.

A food intolerance can occur when your body has difficulty digesting certain foods. When this occurs over time, large food particles (proteins) may enter the blood stream.

What causes food intolerance?

When food particles enter the bloodstream, the immune system can sometimes identify these food protein particles as “foreign” and produces IgG antibodies to “attack” the food in question. This response is your immune system’s natural defence mechanism to ward off harmful invaders in the body which can create inflammation.

This inflammation could trigger bothersome symptoms, which may persist or develop in the body if they are neglected. Imagine that the immune system is working over-time and as the years progress it gets knackered and not as efficient as you would like it to be.  A weak immune system is not able to protect you well not just from food attacks.

Can you develop a food intolerance?

Yes, you can develop a food intolerance at any point in your life. However, it is often very challenging to pinpoint exactly what foods and drinks you’re reacting to.

Food intolerance testing is not something that is currently offered on the NHS. Instead, people are encouraged to eliminate certain foods one-by-one to identify an intolerance, especially ones you suspect are causing a reaction. However, this can often be an exhaustive process and not knowing where to start can be daunting.

If you’re keen to find out if there’s something you’re reacting to in your diet, then we’re here to help. Our lab  analyses your IgG reactions to up to 208 food and drink ingredients and offer post-test aftercare through nutritional consultations, relevant content material and ongoing guidance from our Customer Care team.

Do I need to take a food intolerance test?

It’s important to discuss any symptoms you may have with your GP, so they can refer you for further tests to rule out any underlying conditions. If you are still suffering thereafter, it is at this point where you may wish to take a closer look at your diet.

Do I have a food intolerance?

Symptoms of a food intolerance can often be wide-ranging and affect various parts of the body. From digestive problems, headaches, skin issues through to anxiety and depression. Common food intolerance symptoms include:

  • Diarrhoea

  • Bloating

  • Rashes

  • Headaches

  • Nausea

  • Fatigue

  • Abdominal pain

  • Runny nose

  • Reflux

  • Flushing of the skin


We always encourage to see your GP first to rule out any underlying conditions. Food intolerance is often the last possible cause people investigate for their symptoms. Did you know medically unexplained symptoms account for up to a fifth of GP consultations in the UK? These symptoms include, tiredness, depression, anxiety, skin issues and digestive problems.

An IgG food intolerance test can pinpoint what foods and drinks your body could be reacting to which can be a useful starting point for an elimination diet. Usually there is more than one food and drink ingredient that the body is reacting to and, therefore, an IgG test could override the guesswork on what works for and against your body.

Food intolerances and behavioural issues in children

Almost all children and who are struggling with learning, behaviour and social problems also suffer from food sensitivities. If the brain is out of balance, the digestive system dysfunctions and the immune system gets out of balance. This also works the other way around.  This imbalance ultimately leads to these food sensitivities.  You may read more about this here.

What is an IgG test?

IgG is a fancy word for testing the reaction to proteins in foods. This simple blood test is used as a measurement strategy of food-specific IgG antibodies for identifying foods to which a person may be sensitive. This type of testing is now considered mainstream as many choose to use this approach as a starting point for an elimination diet.

Our lab’s specific IgG antibody programmes test for food-specific IgG antibody reactions to 200+ different whole food extracts. The test is not diagnostic of any condition but is used as an aid to management of dietary intake, a “starting point” for an elimination diet.

How long do the effects of food intolerance last?

The onset of symptoms is usually much slower compared to a food allergy and may be delayed by many hours after eating the offending food. Because of this, it makes it challenging to pinpoint what foods and drinks are triggering your symptoms. The signs of food intolerance are often prolonged, especially if offending foods are eaten on a regular basis.


What’s the difference between a food allergy and a food intolerance?

When it comes to the difference between food allergy and food intolerance, many people assume they are the same thing, especially when they’re used interchangeably in conversation. However, they are both very different.

An allergy could be life-threatening, and symptoms often develop soon after consumption. A food intolerance, on the other hand, is not life-threatening and symptoms could develop as far as 72 hours after eating the problematic food. In scientific terms, the body produces IgE antibodies during an allergic reaction and IgG antibodies can be involved when it comes to a food intolerance. This means that the biological processes behind a food allergy and a food intolerance are notably dissimilar.

You can find out more on the difference between the two here.

Thinking of a food intolerance test? Here’s what to look for:

Good question! It’s fair to say that the market for food intolerance tests is heavily saturated due to an increased demand of interest in health and wellbeing. That’s why it’s important for you, the customer, to make sure you make well-informed choices when it comes to purchasing a food intolerance test.

How are you meant to tell the difference between the plethora of diagnostic tests that are available to you? How can you tell those based on good science and those that have no basis? It’s a difficult task. Luckily, there are simple things you can look out for to check the reputation of a diagnostic test:

  • There should be consumer data to show that the test works – This can come in the form of customer survey results, real-life testimonials or statistics

  • On the topic of statistics, look out for reproducibility stats. This means that two separate results of the same person’s sample should correlate with each other. At our lab, we have a >98% rate

  • Sounds technical, but make sure the test has got a CE mark. This symbol is applied to products which complies with EU safety, health and environmental requirements

  • What post-test support is on offer? You want to get the most of your money so see if you get nutritional consultations included in the programme, guidebooks, food diaries and access to a support team to help you along the way


We’re proud to say that we have all of the above.

How our blood tests compare to other methods:

At your fingertips, you have a range of tests online to choose from. There is hair testing which analyse a sample of your hair against energy fields all the way through to VEGA tests which measure the electromagnetic conductivity in the body. These food intolerance tests often appear to be cost-effective and found on discounted websites, but unfortunately these methods have no scientific basis and are not proven to work.

Results from these types of tests can lead to many foods being eliminated from the diet unnecessarily and research studies show that these tests provide information that is no better than chance


You also have the option to choose the IgG method which, according to one study, “shows promise with clinically meaningful results. It has proven useful as a guide for elimination diets, with clinical impact for a variety of diseases”. This is what our lab expertly specialises in– a leading provider in IgG food intolerance testing.

Our lab is different compared to the many food intolerance companies out there. Not only do they hold substantial evidence to support IgG food intolerance testing, but they are in a unique position with 35 years of experience, a wealth of customer feedback and proven robust methodologies that work.

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