We Do Not Offer Testing Only Services

As the leading functional medicine clinic in the UK, we support our clients in optimising their health and tackling illnesses. To do this we offer tests that help us identify the root cause of their health concerns. With that in mind, our testing services are only for patients under consultation with our expert practitioners.

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Our functional medicine approach offers a variety of treatments including nutritional support, and lifestyle modifications which help to improve your symptoms.


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Irritable bowel syndrome (IBS) is one of the most common digestion disorders we treat at the clinic.

IBS is a disorder that affects the large intestine. Signs and symptoms include cramping, abdominal pain, bloating, gas, and diarrhea or constipation, or both.

IBS doesn’t cause changes in bowel tissue or increase your risk of colorectal cancer. IBS is not diagnosed by colonoscopy, blood tests or MRI. It is a functional bowel disorder.

As a functional medicine clinic, we aim to identify the root cause or causes of IBS, adopting a biopsychosocial approach to restore you back to good health.

What is IBS?

Irritable bowel syndrome (IBS) is the most common gastrointestinal complaint, affecting up to 20% of all UK adults.

It’s believed that 75% of people who have IBS never seek a doctor’s help. Of the minority who do, it accounts for 10% of all doctor’s visits and 50% of referrals to gastroenterologists.

  • 1 in 5 UK adults suffers from IBS
  • 10% of doctor’s visits are due to IBS
  • 3 out of 4 people force themselves to live with their symptoms
  • 50% of gastroenterologist referrals are due to IBS

Over the years, it’s had a variety of names: spastic colon, spastic bowel, mucus colitis, colitis, and functional bowel disease. It’s called ‘functional’ bowel disease because people who have IBS don’t have any obvious changes in bowel structure or other serious complications, and they rarely require hospitalisation. Nevertheless, IBS can significantly restrict a person’s lifestyle.

The most common pattern of IBS is diarrhoea alternating with constipation. Bowel movements (i.e. pooing) usually relieve the discomfort. Other common IBS symptoms include:

  • Abdominal pain and spasms
  • Gas

What causes IBS?

In 20% of cases, IBS is originally triggered by infection. These people are more likely to have diarrhoea-dominant IBS. The infection causes inflammation in the mucosal tissues (the gut lining), which stimulates immune and muscle changes. When the inflammatory response continues over time, the bowels learn to be over or under-reactive to stimuli.

In others, there’s usually no single cause for IBS. By using the functional medicine model, we aim to find the root of the problem in each person, working with him or her individually in response to their biochemical uniqueness.

There are lots of potential causes of IBS. Some of these include:

  • Food sensitivities
  • Lactose intolerance
  • Malabsorption of nutrients
  • Endometriosis

How do we test for IBS?

Testing can be used to investigate the underlying causes of IBS. In our practice, we typically use four different tests:

Comprehensive Digestive Stool Analysis

This stool test provides us with intestinal health markers, giving us insight into your digestive capacity. It enables us to see whether inflammation is present.

The test also looks at infections and pathogens including H.Pylori. These bacteria, yeast/fungi or parasites that may be contributing to your health complaint.

Food Intolerance Testing

There are countless food intolerance tests available on the market. While some of these tests can provide useful insights on occasion, we prefer to use elimination diets with patients—simply because they tend to yield better results.

When we feel a food intolerance test is warranted, we work with Cyrex Laboratories and Dunwoody Labs.

SIBO Testing

SIBO stands for Small Intestine Bacterial Overgrowth. Put simply, it means a person has too much bacteria in their small intestine.

SIBO is viewed as one of the most common causes of IBS, especially the constipation-dominant type. We test for SIBO using something called a hydrogen breath test.

After a 24-hour pre-test protocol—which includes a restricted diet for 12 hours followed by a 12 hour fast—you complete your hydrogen breath test. It takes three hours and requires a breath sample every 20 minutes.

When the results are in, we get to see how much hydrogen and methane gas were produced over this time period. This allows us to see whether you test positive or not for SIBO.

Organic Acids Testing

Bacteria and fungi living in the intestines create breakdown products (known as metabolites) that are excreted in your urine.

If you have elevated values for certain metabolite markers, it may be an indication that you have yeast or bacterial dysbiosis.

What’s the best IBS diet?

We’re all different, so any diet for IBS needs to be tailored to the individual. Based on your clinical history and tests, for example, it may become clear that you require a low FODMAP diet with no grains, while another person would do better on the specific carbohydrate diet.

There’s no one-size-fits-all solution.

There are many dietary approaches that can work well for irritable bowel syndrome. Some examples include:

  • gluten-free diet
  • a grain-free diet
  • the specific carbohydrate diet
  • a low histamine diet
  • a gluten and dairy-free diet
  • the low FODMAP diet
  • the GAPS diet

How do we support IBS?

In the functional medicine model, we also pay a lot of attention to the mental, spiritual and emotional aspects of people’s health. Our bodies are a reflection of what’s going on in our emotional life, so the importance of mindset cannot be underestimated.

Our functional medicine model uses a systems-biology approach to understand the underlying causes of IBS. Some of these include:

  • Motility disorders
  • Imbalances in the microflora, also known as dysbiosis
  • Overgrowth of certain bacteria that are associated with systemic illness

Our consultation process for IBS

We aim to get to the root cause if your IBS symptoms, addressing them via a jointly agreed nutritional and lifestyle protocol.

Step 1: Pre-consultation

We offer a discovery call to best match you to the most suitable practitioner for your needs. You’ll then receive a questionnaire and a food diary to fill in ahead of your session.

Step 2: Initial Consultation

Together we gather a detailed picture of your health, and further testing will be recommended if necessary. You’ll come away with a nutritional and lifestyle protocol.

Step 3: Follow-up Consultations

We ensure your progress through regular meetings. These give you the opportunity to talk about your experiences, review test results and make adjustments where necessary.


Suspect you have IBS or want to learn more? Please give us a call today on 0203 332 0030.


” Nishta has been extremely supportive and helpful with my daughter who was experiencing severe IBS symptoms. She had an immediate instinct of what could be the underlying issues causing the problem and was more helpful than her gastroenterologist
in getting to a diagnosis. It was so reassuring to have her support during a very worrying time
Thank you so much. ”


” I came to Oliver after having years of IBS and being told the same thing by GP’s who don’t seem to take the symptoms of IBS seriously. I had constant bloating and difficultly passing stools. After a few sessions with Oliver he took a detail look at my life-style and my eating habits and recommend several changes along with herbs and supplements to cleanse and rebuild my gut.
My symptoms have improved greatly and have pretty much disappeared. I know where to turn if I have any issues in the future regarding my health. ”


” Oliver really helped me with my stomach problems. I had been an IBS sufferer for many years and things had reached a crisis point in which I seemed to be becoming very intolerant of a whole range of normal, everyday foods – resulting in severe diarrhoea. I was starting to restrict my diet in quite drastic ways. Oliver arranged for some tests which set my mind at rest and put me on a comprehensive plan of supplements, as well as giving me detailed, practical advice on diet.
Things improved a lot within a couple of months. I no longer feel any need to restrict my diet but I’ve got into the habit of making more healthy choices. ”


Health and Nutrition Resources

Understanding and Treating Small Intestinal Bacterial Overgrowth (SIBO)

Leaky Gut syndrome, IBS and food sensitivity

Bloating, stress and inflammation via the gut-brain axis (GBA)

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