Irritable bowel syndrome is one of the most common gastrointestinal diagnoses, and one of the least satisfying. For many patients, the diagnosis amounts to confirmation that something is wrong without meaningful explanation of why, and without a clear treatment pathway beyond dietary restriction and stress management advice that, while not wrong, rarely gets to the root of the problem.
Bloating, altered bowel habit, abdominal pain and discomfort are not conditions to simply manage. They have causes, and those causes can be identified and addressed.
Why IBS Is Not a Single Condition
The label IBS describes a pattern of symptoms rather than a specific pathological process. Patients who fit the diagnostic criteria may have arrived at their symptoms through entirely different mechanisms: gut microbiome dysbiosis, visceral hypersensitivity, impaired gut motility, small intestinal bacterial overgrowth (SIBO), dysregulated gut-brain signalling, food intolerances, impaired digestive enzyme production, or some combination of these. The treatment that resolves the condition depends entirely on which of these mechanisms is operating in that individual.
This is why generic dietary advice, including the commonly recommended low-FODMAP approach, produces good results for some patients and minimal improvement for others: it addresses one potential mechanism without establishing whether that mechanism is actually present.
The Role of the Gut Microbiome
The gut microbiome, the community of microorganisms inhabiting the large intestine, plays a central role in digestive health. Dysbiosis, an imbalance in the composition of this community, is associated with altered fermentation patterns, increased intestinal permeability, local inflammation and altered gut motility, all of which can produce or contribute to IBS symptoms. The microbiome is influenced by diet, antibiotic use, stress, sleep and a range of other factors, and it can be assessed through functional stool testing.
Food Intolerance vs Food Allergy
Food allergy involves an IgE-mediated immune response and typically produces rapid, clear-cut reactions. Food intolerance is a different phenomenon: a non-immune-mediated reaction that is often delayed by hours or days, variable in severity and dependent on the quantity consumed and the overall state of the digestive system at the time. This delay makes self-identification of intolerances unreliable, and elimination diets conducted without clinical guidance frequently produce unnecessary restriction without resolving the underlying problem.
Small Intestinal Bacterial Overgrowth
SIBO, the presence of excessive bacteria in the small intestine, produces fermentation of carbohydrates in a location where it should not occur, generating gas and triggering symptoms that closely mirror IBS. It is underdiagnosed in primary care, responds to specific treatment protocols and can be assessed through breath testing.
What a Clinical Nutrition Assessment Looks Like
Claire Ward’s approach to digestive health begins with a detailed clinical and dietary history, mapping the symptom pattern, its onset, its triggers and its relationship to diet, stress and other variables. From this she identifies which mechanisms are most likely to be involved and recommends the most appropriate functional testing to confirm or rule out specific contributors.
The resulting protocol is precise and targeted: not a blanket elimination diet but a structured intervention addressing the specific drivers identified in that individual’s case. Rebuilding digestive function, rather than simply avoiding triggers, is the goal.
If your digestive symptoms have not been adequately explained or resolved, book a clinical nutrition consultation with Claire at Hever Health.