Food Intolerance | Gut Health | London Doctors Clinic


Food Intolerance Testing

Food Intolerance Test | Gut Microbiome Test

What is food intolerance?

Food intolerance testing is designed to identify the food that make some people unwell. People with sensitivities or intolerances to certain food can experience adverse reactions. This can be a recurring reaction, happening each time a person ingests the food. Food sensitivity/intolerance causes difficulty in digesting certain foods which can lead to an unpleasant reaction such as bloating, abdominal pain, intestinal gas or diarrhoea.

What is your gut microbiome?

Your ‘gut microbiome’ is made up of billions of bacteria and other microorganisms that co-exist with other human cells in the lower intestine. These microorganisms, mainly comprising bacteria, are involved in functions critical to your health and wellbeing. The gut microbiome is responsible for aiding digestion, absorbing nutrients, regulating vitamin levels and supporting the immune system.

The microbiome is strongly influenced by external factors like eating habits, antibiotics, illness, stress and more. This means that you can strengthen it by modifying your diet. Even if you eat a good diet, your microbiome might still lack the ability to synthesise specific vitamins or breakdown dietary fibre.


We offer two home tests to help identify food intolerances and assess your gut microbiome.

Food Intolerance Test – Blood sample (self-collection)

  • Optional Nutritional Therapist consultation for £30

£249: Results in 3 days. 

Gut Microbiome Test – Stool sample (self-collection)

  • Optional personalised diet-plan for £86

£139: Results in 4-5 weeks. 


What causes food intolerance?

It is often unclear why a person is sensitive to certain foods. Common causes include:

  • Lactose intolerance: meaning your body can’t digest lactose.
  • Wheat intolerance: some people find wheat simply hard to digest.
  • Food additives: for example, artificial sweeteners or flavour enhancers.
  • Chemical causes: for example, caffeine or amines found in cheeses.
  • Contaminant causes: for example, toxins, viruses, bacteria or parasites that have contaminated foods.

What are the symptoms of food intolerance?

In general, people who have a food intolerance tend to experience:

  • Abdominal pain
  • Bloating
  • Intestinal gas
  • Diarrhoea
  • Joint pain
  • Headaches & migraines
  • Skin rashes or itching
  • Fatigue

How do I treat food intolerance?

The only way to manage a food intolerance is to stop eating the food for a while and then reintroduce small quantities while monitoring how much you can eat without causing symptoms.

Taking an IgG food intolerance test is a quick, easy and accurate way of identifying your unique trigger foods and drinks.

You will receive a guide which will provide useful hints, tips, and expert guidance to ensure you can follow a new diet that is delicious and nutritious, all whilst removing or reducing consumption of your problem foods and drinks.

How does the test process work?

The Brunel Health IgG Food Intolerance Test is a quick, accurate and reliable way of identifying unique food reactions. The test analyses 134 relevant food and drink antigens, in categories of:

  • Grains & Staples
  • Dairy & Eggs
  • Protein Supplements
  • Fruits & Vegetables
  • Herbs, Spices & Oils
  • Meat & Seafood
  • Nuts, Seeds & Beans
  • Drinks

How do I complete a food intolerance test?

Your test kit will be shipped to your door which includes everything required to take a finger-prick blood sample. Following the analysis of your blood sample, you will receive a 12-page report detailing exactly which ingredients you have reacted to, and the level of severity of the reaction.

How much does it cost?

Test price is £249

You can also choose to add an optional Nutritional Consultation. For just an extra £30, you can have a 30-minute telephone consultation with a CNHC registered Nutritional Therapist to help implement and action your results.

What happens after I receive my results?

Taking an IgG food intolerance test is a quick, easy and accurate way of identifying your unique trigger foods and drinks.

With the help of your report, and supplementary food intolerance guidebook you can optimise your diet based on the results, ensuring your diet is bespoke and just right for you! Following the test results is a great way to start a guided elimination diet, optimising your intake of foods and drinks based on your personal test results.


Gut Microbiome Testing

How will a gut health test help me?

The test analyses the DNA of your bacteria and the types of bacteria present. It provides information about the various functions of your gut bacteria, like the extent to which they protect you against certain diseases and inflammation, as well as what vitamins they synthesise. You will receive recommendations to improve and maintain the balance of your microbiome by adding specific foods to your diet.

How do I complete the Microbiome test?

Your test kit will be shipped to your door which includes everything to collect a stool sample. You provide the bio-sample and post it to the lab where your results will be processed within 4-5 weeks. Your results will include a detailed online report with personal lifestyle recommendations.

Why is it important?

There is no one ideal ‘Healthy Gut’, each person has a unique bacterial footprint. In order to find out how to boost your gut health, you need to know how your individual microbiome is performing so you can find out exactly what you need to do in order to support it.

How is my gut health sample analysed?

Your sample is analysed in the lab using Illumina technology. The DNA fragments in your sample are studied to identify your microbes and evaluate their proportion in the microbiome.

What is the cost of a Gut Microbiome Test?

Test price is £139

What happens after I receive my results?

Gut bacteria are influenced by external factors such as diet, lack of essential nutrients may cause some bacterial species to die off. In this case, it is important to have diversity, so that other bacteria can fulfil these functions and prevent pathogenic species from moving in. The diversity can be maintained by having a healthy diet.

In addition to dietary recommendations that come with your report, our Dietitian can assist you with building a personalised diet plan to strengthen your gut health. Adding on a personalised diet plan is an optional extra you can purchase for £86.

Test price plus consultation is £225. 


Buy your test online

Click the button below to order your food intolerance or gut microbiome test online. You will have the option of adding the additional consultation or nutritional plan on the order form.

Frequently Asked Questions

What different types of tests are available?

Two tests are currently available. They are:

Food Intolerance Test – £249 (£279 includes a Nutritional Consultation)

Gut Microbiome Test – £139 (optional Dietitian Consultation can be added for £86)

When should I get tested?

You can get tested for a food intolerance at any time. A food intolerance does not involve your immune system. There is no allergic reaction, and it is never life-threatening. If you regularly have diarrhoea, bloating, tummy pain or skin rashes but you’re not certain of the cause, please see a GP.

Can I take the test if I am sick or taking medication?

We recommend that you collect a stool sample in the absence of gastrointestinal symptoms. Additionally, if you have been taking antibiotics, a course of NSAID’s or have undergone surgery, please wait three months before taking the Atlas Biomed Microbiome Test.

How long do results take to come back?

The Food Intolerance Test results are received within three days.  

The Gut Microbiome Test is more complex therefore results are received within 4-5 weeks.

What can I do to improve my symptoms?

After completing the Food Intolerance test, you will receive a 12-page report detailing exactly which ingredients you have reacted to and includes expert guidance to ensure you can follow a new diet to remove or reduce consumption of your problem foods and drinks. If you require further advice, we offer a Nutritional Consultation.

Where can I get more advice?

To get more advice about a suspected food intolerance, you can opt to have a 30-minute consultation with a Nutritionist to help implement and action your results.

If you need further advice on weight management, gastrointestinal conditions or nutrition support you can book a 60-minute video appointment with our Dietitian for just £100.