What Does the NHS Say About Food Intolerance?
IBS vs Intolerance Explained
An honest look at food intolerance, IBS, and where testing genuinely fits in
If you've been told your bloating, fatigue or digestive discomfort is 'just IBS,' you're not alone, and it's worth understanding what that label does and doesn't explain.
Contents
What the NHS says about food intolerance
IBS vs food intolerance: what's the difference
Why food intolerance symptoms are so hard to spot
What the NHS says about home testing, and where practitioner-led testing differs
Why guessing rarely works
A structured, personalised approach
FAQs
What the NHS says about food intolerance
The NHS has long acknowledged food intolerance as a genuine issue, distinct from a food allergy. Its guidance describes common intolerances (to things like lactose, gluten, caffeine and certain food additives), the kinds of symptoms that can result, including bloating, stomach pain, diarrhoea, skin reactions and fatigue, and recommends keeping a food and symptom diary as a first step, alongside speaking to a GP or registered dietitian for persistent or severe symptoms.
Worth being accurate here: this isn't a new policy or a sudden 'recognition,' it's fairly established, standard NHS guidance, most recently reviewed in mid-2026 as part of routine content maintenance. What is worth knowing is that a structured approach, tracking symptoms, then testing and reintroducing systematically, is consistent with how the NHS frames good practice for identifying triggers.
IBS vs food intolerance: what's the difference
IBS is a symptom-based diagnosis. It describes a pattern, bloating, pain, and changes in bowel habits, but it doesn't necessarily explain why those symptoms are happening. For some people, an underlying food intolerance is part of that picture. For others, it isn't, IBS can have several contributing factors, including gut motility, the gut microbiome and stress. An IBS diagnosis and a food intolerance aren't mutually exclusive, and aren't automatically the same thing either.
Why food intolerance symptoms are so hard to spot
Unlike allergies, food intolerance reactions are typically delayed (often hours or even days later), inconsistent, and difficult to track without some structure. You might eat a food today, feel fine, then feel unwell tomorrow. No wonder it's confusing, and no wonder random elimination rarely gets to a clear answer on its own.
What the NHS says about home testing, and where practitioner-led testing differs
It's worth being upfront about this, because it matters: NHS guidance specifically advises against unregulated home food intolerance test kits, on the grounds that there's limited evidence they give accurate or clinically meaningful results. That caution is aimed at unsupervised, direct-to-consumer kits bought without any professional interpretation attached.
This is genuinely relevant to how testing is approached here. At FIT, IgG-based food intolerance testing is a debated area within the wider allergy field too, several allergy bodies have raised similar concerns that IgG antibody levels mainly reflect food exposure rather than proven intolerance on their own. That's why results are never handed over as a standalone report, they're interpreted by a registered nutritional therapist alongside your symptom history, and used to guide a structured elimination and reintroduction process rather than treated as a definitive diagnosis in themselves.
Why guessing rarely works
Many people try to manage symptoms by cutting out foods randomly, following generic advice, or attempting elimination diets alone. Without guidance, this often becomes restrictive, stressful and inconclusive, and can lead to unnecessary long-term avoidance of foods that were never actually the problem.
A structured, personalised approach
At FIT, the focus is on advanced food intolerance testing, expert interpretation rather than a raw report, structured elimination (not cutting everything at once), guided reintroduction, and a personalised nutrition and lifestyle plan built around your results. Our Advanced Food Intolerance Assessment is built this way.
If you've been told your symptoms are 'just IBS,' that doesn't mean they aren't real, valid, or worth investigating properly. Understanding what's actually driving them tends to matter more than the label attached to them.
FAQs
Does the NHS recognise food intolerance testing? The NHS recognises food intolerance as a genuine issue and recommends a structured, symptom-tracking approach, but specifically advises against unregulated home test kits due to limited evidence of accuracy. This is different from practitioner-led testing with professional interpretation, though the underlying caution about testing in isolation, without proper guidance, applies either way.
Can you have IBS and a food intolerance at the same time? Yes. IBS is a symptom-based diagnosis, and a food intolerance can be one of several contributing factors behind it, though not everyone with IBS has an underlying food intolerance.
How is food intolerance actually diagnosed? There's no single perfect test. A food and symptom diary, combined with structured elimination and reintroduction, is the NHS-recommended starting point. Practitioner-led testing can help target which foods to focus on, provided it's interpreted alongside your symptoms rather than used alone.
Should I try an elimination diet on my own first? You can, but unstructured elimination often leads to excessive restriction without a clear answer. A structured approach, ideally with professional guidance, tends to get to a useful conclusion faster and with less unnecessary food avoidance.
About Becki Hawkins
Becki Hawkins, BSc (Hons), mBANT, CNHC, is the founder of FIT Nutrition & Testing Clinic and a Registered Nutritional Therapist with over 20 years of experience. She specialises in evidence-based personalised nutrition and functional testing, helping clients uncover the root causes of digestive issues, hormonal imbalances, and unexplained symptoms. Becki combines clinical expertise with culinary creativity, translating complex test results into practical, delicious nutrition plans that work in real life. Her approach is simple: test, don't guess. Because guessing doesn't heal. Knowing does.