FOOD INTOLERANCE NATUROPATH · MAROOCHYDORE, SUNSHINE COAST & ONLINE
Food Intolerances & Food Sensitivities
Support for digestive symptoms, confusing food reactions and increasingly restricted diets
If more and more foods seem to trigger bloating, pain, diarrhoea or nausea, it can become difficult to know what is genuinely causing the reaction, or what is still safe to eat.
The reaction may be real, but the food itself may not be the whole explanation. The timing, amount eaten, combination of foods, underlying digestive pattern and type of reaction all help determine what the next step should be.
When eating starts to feel unpredictable
Some food reactions are clear and reproducible. Others are far less consistent: a food is tolerated one week and uncomfortable the next, or a similar meal produces a different response. The list of suspected foods grows, yet avoiding them does not make digestion reliably better.
You may recognise this pattern
You react to foods you previously ate without difficulty
The amount you tolerate varies from one day to another
Symptoms build after mixed meals, making one ingredient difficult to identify
You have removed gluten, dairy or several FODMAP groups but remain symptomatic
You feel temporarily better on a restricted diet, then symptoms return
Your “safe food” list is becoming smaller and eating away from home feels stressful
Food reactions are not all produced by the same mechanism. A useful assessment starts by defining the pattern rather than placing every symptom under the label of “food sensitivity.”
WHAT THE TERM MEANS
Food intolerance is not the same as food allergy
“Food sensitivity” is a broad, non-specific term. People often use it to describe almost any unwanted symptom after eating, but it is not one clearly defined diagnosis.
A food allergy involves an immune reaction to a food protein. Reactions may include hives, swelling of the lips, face or eyes, vomiting, wheeze, throat tightness, difficulty breathing, dizziness or collapse. Suspected food allergy requires medical assessment and, where appropriate, referral to a clinical immunology or allergy specialist.
A food intolerance does not usually involve the same allergic mechanism. Symptoms are often digestive and may depend on the amount consumed. Lactose intolerance is one example.
Other reactions may relate to fermentable carbohydrates, naturally occurring food chemicals, coeliac disease, an existing gastrointestinal condition or the way a sensitive gut responds to normal digestion.
The distinction matters because the appropriate investigation, and the level of avoidance required, can be completely different.
A food can trigger genuine symptoms without the reaction being an allergy, and a negative allergy test does not explain every form of food intolerance.
The same symptom can have more than one explanation
Bloating after bread does not prove gluten intolerance, and diarrhoea after dairy does not automatically mean milk allergy.
Several mechanisms can produce similar symptoms.
Enzyme-related intolerance
In lactose intolerance, reduced lactase activity means lactose is not fully broken down. The amount consumed often matters, and some people tolerate smaller serves or lower-lactose foods.
Food allergy
Food allergy may cause rapid symptoms affecting the skin, digestive tract, breathing or circulation. It should not be diagnosed through intolerance tests or managed through unsupervised food challenges.
Digestive conditions can change food tolerance
IBS, inflammatory bowel disease, gastrointestinal infection, altered bowel motility and other digestive conditions can affect how meals are tolerated. The food may expose the symptoms without being the underlying diagnosis.
Coeliac disease
Coeliac disease is an immune-mediated condition triggered by gluten. It is not a food intolerance and requires strict, lifelong gluten avoidance once properly diagnosed. Testing becomes less reliable after gluten has already been removed.
This is why identifying a symptom-producing food is useful, but it is not always the end of the assessment.
DOSE & CONTEXT
Why a food may cause symptoms sometimes, but not every time
Many non-allergic food reactions are threshold-dependent. A small amount may be tolerated, while a larger serve produces symptoms.
The total meal matters too. Several individually tolerated foods may collectively exceed a person’s current threshold. This can make the final food eaten appear responsible when the entire meal created the load.
Tolerance may also be influenced by:
Portion size
The combination of foods eaten together
Whether several fermentable foods are consumed in one sitting
Bowel function and the degree of constipation present
Menstrual cycle changes in digestive sensitivity
A recent gastrointestinal illness
Alcohol, caffeine, stress or a particularly high-fat meal
Stress does not mean the symptoms are imagined. The gut and nervous system communicate continuously, and a more sensitive digestive system can respond more intensely to distension and normal intestinal activity.
Variability is therefore information. It may suggest that dose and digestive context matter more than permanent intolerance to the food itself.
FODMAPS & IBS
When multiple foods trigger bloating, pain or altered bowel habits
FODMAPs include fructans, galacto-oligosaccharides, lactose, excess fructose and polyols. They occur across many nutritious foods, including wheat, onion, garlic, legumes, dairy products, fruit and some vegetables.
In people with IBS, FODMAPs can increase water and gas within the bowel. A gut that is more sensitive to stretching may experience this as pain, pressure, visible distension or an urgent change in bowel habit. This does not mean FODMAPs are inflammatory, damaging or “bad” foods.
A structured low-FODMAP trial can be useful when the symptom pattern fits IBS, but the restrictive phase is intended to be temporary. Foods are then systematically reintroduced to identify which groups and serving sizes matter for that individual.
Remaining on an unnecessarily strict low-FODMAP diet can reduce variety, make social eating difficult and leave someone avoiding foods they may tolerate perfectly well.
WHEAT OR GLUTEN
Bread causes symptoms, but is gluten necessarily the problem?
Wheat contains several components that can be relevant to digestive symptoms.
Gluten is the protein that triggers coeliac disease. Wheat also contains fructans, a type of FODMAP that can contribute to bloating, gas and pain in some people with IBS.
Someone may therefore feel better after removing bread and pasta without knowing whether the relevant change was less gluten, fewer wheat fructans or a broader change in the way they were eating.
That distinction has practical consequences. Coeliac disease requires strict, lifelong avoidance of gluten. Fructan sensitivity is usually dose-dependent and does not necessarily require complete avoidance of wheat or every trace of gluten.
If coeliac disease is a possibility, speak with your GP before beginning a gluten-free diet. Coeliac blood tests and biopsy are most reliable while gluten is still being consumed. Removing it first can lead to inaccurate results and may require a supervised gluten challenge later.
WHY TOLERANCE CAN CHANGE
“I used to eat this without a problem. What changed?”
A new reaction does not automatically mean the body has developed a permanent intolerance to that food.
Sometimes the change is relatively direct, such as lactose intolerance becoming more noticeable after gastroenteritis. In other cases, food reactions appear within a broader shift in bowel function and digestive sensitivity.
The surrounding timeline can help determine what deserves investigation:
Did symptoms begin after food poisoning, antibiotics, travel or another illness?
Is constipation causing symptoms to build as the day progresses?
Are reactions confined to large serves or mixed meals?
Did symptoms begin alongside weight loss, bleeding, anaemia or persistent diarrhoea?
Has the diet become progressively more restricted?
Were coeliac disease, inflammatory bowel disease or other medical causes assessed before foods were removed?
SIBO may be relevant for some people with persistent bloating and altered bowel habits, but symptoms after food do not diagnose it. Breath testing is most useful when the clinical pattern supports a specific question and the result would change treatment.
TESTING
Can a food sensitivity test tell you exactly what to avoid?
There is no single blood test that can reliably identify every non-allergic food reaction.
Food-specific IgG panels are commonly marketed as “food sensitivity” tests, but IgG antibodies generally reflect exposure to a food rather than proving that it is causing symptoms. Professional allergy organisations do not recommend IgG testing to diagnose food allergy or intolerance.
Large panels can produce long lists of positive foods. Removing them may create unnecessary restriction and anxiety without addressing the actual digestive pattern.
Useful investigation depends on the suspected mechanism.
Testing may include
Coeliac serology while gluten is still being consumed
Lactose or fructose breath testing where the history supports it
Allergy assessment when symptoms suggest an immune-mediated reaction
Medical investigation for persistent diarrhoea, bleeding, weight loss, anaemia or inflammatory features
Hydrogen and methane breath testing when SIBO or IMO is a credible clinical question
For many non-allergic reactions, a structured food-and-symptom history followed by a time-limited elimination and planned reintroduction is more informative than a broad test panel.
Removing a food can provide relief, but it does not always prove the cause
A carefully chosen elimination can help establish whether a food or food group is contributing to symptoms. The quality of the reintroduction matters just as much as the removal phase.
If several foods are removed simultaneously and symptoms improve, it may be impossible to know which change mattered. If foods are never reintroduced, a short-term experiment can quietly become a long-term restricted diet.
Restriction also changes several variables at once. Removing dairy may reduce lactose, fat or total food intake, while removing gluten often reduces wheat fructans as well. Feeling better is useful information, but it does not automatically identify the mechanism.
A stronger process has a defined question:
What reaction are we trying to reproduce or reduce?
Which food component is most plausible?
How long will the trial run?
What will count as a meaningful response?
How and when will the food be challenged again?
The goal is the broadest varied diet that can be eaten comfortably, not permanent restriction for its own sake.
01 — Define the reaction
We clarify the symptoms, timing, severity and consistency. A reaction beginning within minutes is assessed differently from bloating that builds over several hours or symptoms that emerge only after a large mixed meal.
02 — Reconstruct the timeline
We examine when tolerance changed, what was happening with bowel function, whether symptoms followed illness or treatment, and which investigations have already been completed.
03 — Assess dose and reproducibility
The amount eaten, food combinations and response on different occasions help distinguish a reproducible trigger from a threshold effect or an incorrectly blamed ingredient.
04 — Review the current diet
We look at what has already been removed, whether those exclusions improved symptoms and whether the remaining diet provides enough energy, protein, fibre and micronutrients.
05 — Identify what requires testing or referral
Suspected allergy, coeliac disease, inflammatory symptoms or other red flags require the appropriate medical pathway. Digestive testing is considered only when it answers a defined clinical question.
06 — Build a structured next step
The plan may involve symptom stabilisation, a targeted short-term dietary trial, treatment of a relevant digestive condition and planned food reintroduction. Progress is measured by both symptom change and the ability to maintain or expand dietary variety.
MY APPROACH
Making sense of the reaction pattern
When food feels unpredictable, the first task is not to remove more of it. It is to establish what kind of reaction is occurring and whether the pattern points to one food, a dose threshold or a broader digestive issue.
You do not need to know which food is responsible before booking
You may have one suspected trigger, several inconsistent reactions, an IBS diagnosis or a diet that has become increasingly difficult to manage.
Your initial consultation can be used to organise the reaction pattern, review what has already been investigated and decide whether the next step should involve medical testing, a targeted dietary trial, digestive assessment or structured reintroduction.
Consultations are available in Maroochydore and at Kunara Marketplace in Forest Glen on the Sunshine Coast, and online throughout Australia.
Frequently asked questions
-
It can appear that way. Tolerance may change after gastrointestinal illness or alongside a broader change in bowel function and digestive sensitivity. The reaction pattern and timeline help determine whether a specific intolerance, another digestive condition or a dose-related threshold is more likely.
-
It depends on what is being tested. There are established investigations for specific conditions, including coeliac serology, allergy testing and some carbohydrate breath tests. Broad food-specific IgG panels are not recommended for diagnosing food allergy or intolerance.
-
Not necessarily. FODMAP-related symptoms, for example, can result from fermentation, water movement and sensitivity to intestinal stretching rather than damage caused by the food. Medical investigation is important when symptoms or pathology suggest inflammation, coeliac disease or another organic condition.
-
Not automatically. Removing both at once makes it harder to identify what changed and may create unnecessary restriction. Coeliac testing should also be considered before gluten is removed. The best starting point depends on the symptom pattern and current diet.
-
Sometimes. Tolerance may improve when the relevant digestive issue is addressed, bowel function stabilises or foods are reintroduced at an appropriate dose. Some diagnosed conditions require lasting avoidance, so the goal depends on the mechanism rather than assuming every intolerance is permanent, or temporary.