In brief
Symptoms after eating certain foods. A food allergy involves the immune system and can be dangerous, while a food intolerance does not involve the immune system.
- Anaphylaxis, a severe allergic reaction, is an emergency. Use an adrenaline autoinjector if one is available, then call triple zero (000).
- Common triggers of anaphylaxis include milk, eggs, peanuts, tree nuts, seafood, bee stings and some medicines.
- Breath tests and biopsies for lactose and fructose intolerance are not recommended, because they can give inaccurate results.
When to get help
Get help now
- Anaphylaxis is an emergency. Signs include difficult or noisy breathing, a swollen tongue, swelling or tightness in the throat, difficulty talking, wheeze, or persistent dizziness or collapse. Use an adrenaline autoinjector if one is available, then call triple zero (000).
Source: healthdirect Australia, Anaphylaxis.
See your doctor if
- You think a food is causing your symptoms.
- You have lost weight or have blood in your poo.
Things that can contribute
- Food intolerances
- Irritable bowel syndrome
- Coeliac disease
- Food allergy
Questions you could ask your GP
- Should I be tested for coeliac disease or food allergy?
- Could a dietitian guide an exclusion diet?
- Are the tests I have seen advertised reliable?
Based on healthdirect Australia, Food intolerance and testing. You can also check your symptoms with the healthdirect Symptom Checker, or speak with a registered nurse on 1800 022 222.
How it works
A food intolerance happens when your digestive system cannot break down or absorb a certain food. It can cause constipation, diarrhoea, bloating, gas, nausea, stomach aches, migraines and fatigue, hours or days after eating. Common culprits include lactose, gluten, fructose, histamines, sulfites and glutamates such as MSG.
There are no specific tests for food intolerance, and healthdirect warns that many advertised tests lack the proof to show they are reliable. A doctor or dietitian can guide an exclusion diet and reintroduction. Coeliac disease is an autoimmune condition, so keep eating gluten until you have been tested.
Connections
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Reactions to food is linked with
Food intolerances can cause bloating, gas and stomach aches.
Source: healthdirect Australia, Food intolerance and testing
If you think gluten affects you, do not stop eating it until coeliac disease has been tested for and officially diagnosed.
- Histamine intolerance Emerging
Histamine intolerance happens when the body does not have the right type or amount of enzymes, and it can cause symptoms hours or days after eating.
Source: healthdirect Australia, Food intolerance and testing
Sources
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Summarised from healthdirect. Sources read on 12, 13 and 16 October 2026. General education only, not medical advice. Spotted a mistake? Please tell us through the HuBu-Intel contact page.