Lab testing for digestive health

One of the main problems that many nutritional therapy clients experience is digestive symptoms. We know that IBS (irritable bowel syndrome) covers a wide range of symptoms, and these include bloating and excess gas often after eating a meal, alternating diarrhoea and constipation, abdominal discomfort, inflammation, skin disorders, with associated low energy and poor sleep. This also contributes to anxiety and raised stress levels.

Understanding digestive symptoms 

It's helpful to find the root cause of these symptoms. When there are imbalances in friendly and unfriendly bacteria, this will increase inflammation and intestinal permeability (leaky gut).

This happens when the mucous lining of the gut (intestine) becomes damaged and allows toxins to leak through the semipermeable lining into the bloodstream. In a 2020 study of patients with these symptoms, the diversity of gut flora was reduced compared to a healthy control group (1).

These toxins may trigger an inflammatory response in the body. Too many unfriendly bacteria compared to the amount of friendly bacteria populating the gut can be a factor contributing to these symptoms.

This may have resulted from antibiotic use, lowered immunity, infections, high stress levels, hormone imbalances, parasites, infections, ingesting certain foods, or often more than one of these factors (2). 

Stool testing and microbiome balance

Lab testing is available from registered nutritional therapists. From a stool sample, an accurate, detailed analysis of imbalances in gut flora can be made in the whole digestive tract, including IBS.

What can gut testing reveal?

This helps find the root causes of digestive symptoms. These include skin disorders, nutrient malabsorption and weight issues. A 2014 clinical research study highlights the benefits and improved health outcomes when stool testing is used for these symptoms (3). Lab results are used in a clinic with registered nutritional therapists to give dietary and supplement recommendations, to help rebalance and restore optimum health.

Breath testing for SIBO

You may be wondering if your symptoms are caused by small intestinal bacterial overgrowth (SIBO). Symptoms may include bloating, flatulence, abdominal discomfort, and diarrhoea. A study in 2020 from Smolinska et al. found that breath testing can provide current insights into the balance of the digestive microbiome. This includes abdominal pain, bloating, and constipation (4).

Breath testing for SIBO analyses and identifies microbiome imbalances, using a handheld device to measure hydrogen and methane levels. These imbalances and root causes are then assessed in a clinic and recommendations made for your diet, with herbal and food-based supplements prescribed to rebalance levels. 

Factors that may influence digestion

Often, small imbalances in friendly and unfriendly bacteria, and fungal overgrowth can have significant effects on digestive function. Nutrients, including the balance of vitamins and minerals, affect the acid/alkaline balance and contribute to digestive function.

A full assessment of your diet and lifestyle is also made at your consultation, following completion of a food diary. Sometimes the foods we like eating the most are the ones contributing to symptoms. These foods can be identified with an antibody finger tip lab blood test. This will give the level of reactivity of each food, helping to find the root cause of digestive symptoms.  

Stress levels may also be affecting your digestive problems, another factor that needs to be assessed. Raised stress levels affect the digestive process, often leading to longer-term disruption that can be assessed and addressed if root causes are found. The connection between the gut and the brain, often affected by the immune system, all contribute to digestive problems and IBS. Finding these root causes is key to finding solutions to the problem. 

Hormones and digestive symptoms 

Balanced digestive function supports healthy hormone balance. Addressing any imbalances in gut bacteria and optimising gut health helps to support and regulate hormones. A healthy, diverse gut microbiome with a wide range of different friendly bacteria is critical for hormonal balance. 

Diet and digestion

By eating a wide range of colourful foods, 'Eating a Rainbow' every day and avoiding processed foods, this will encourage diversity in the microbiome (healthy range of friendly bacteria).

Foods to include are a range of vegetables, fruits and fermented foods, which naturally provide friendly bacteria to help break down foods and populate the gut with friendly bacteria. Fermented foods have been shown to support a healthy microbiome (gut flora) and have benefits to health in a 2022 study (5).

Registered nutritional therapists may recommend any of these lab tests, or an IgG antibody food sensitivity lab test, combined with clinical assessment of diet and lifestyle, with recommendations made for changes to your diet. All factors that may be contributing to your digestive symptoms are assessed fully at your consultation. 

References

Wei W, Wang HF, Zhang Y, Zhang YL, Niu BY, Yao SK. Altered metabolism of bile acids correlates with clinical parameters and the gut microbiota in patients with diarrhea-predominant irritable bowel syndrome. World J Gastroenterol. 2020;26(45):7153-7172. doi:10.3748/wjg.v26.i45.7153

Morales PS, Wijeyesekera A, Robertson MD, et al. A focus group study to assess perspectives of patients with irritable bowel syndrome on human milk oligosaccharides and lifestyle insights. Eur J Nutr. 2025;64(5):196. doi:10.1007/s00394-025-03719-5
https://journals.sagepub.com/doi/pdf/10.7453/gahmj.2013.100

A. Smolinska et al. Volatile metabolites in breath strongly correlate with gut microbiome in CD (Crohn’s disease) patients, Analytica Chimica Acta. (2020) 1025: pp 1-11. DOI: 10.1016/j.aca.2018.03.046

Kumpitsch C, Fischmeister FPS, Mahnert A, Lackner S, Wilding M, Sturm C, Springer A, Madl T, Holasek S, Högenauer C, Berg IA, Schoepf V, Moissl-Eichinger C. Reduced B12 uptake and increased gastrointestinal formate are associated with archaeome-mediated breath methane emission in humans. Leeuwendaal NK, Stanton C, O'Toole PW, Beresford TP. Fermented Foods, Health and the Gut Microbiome. Nutrients. 2022 Apr 6;14(7):1527. doi: 10.3390/nu14071527. PMID: 35406140; PMCID: PMC9003261.