Food Allergy, Food Intolerance and Coeliac's Disease - The Differences Explained


What's causing my symptoms?

It is estimated that food sensitivity of some description affects up to one third of the Australian population. The Australian Bureau Of Statistics last checked the data from 2011 to 2012 and estimated that 17% of our population had a diagnosed allergy or sensitivity.


We estimate that this number needs to be doubled in 2018. There is no doubt that this number is rising each year and we must also consider that food sensitivities are one of the most commonly under-diagnosed conditions. Many patients reporting several years of doctors visits prior to finally getting the help they need.


Taking these factors into consideration it is safe to estimate that around one quarter to one third of the Australian population is currently suffering with some form of food reaction.


So why is it such a challenge to get an accurate diagnosis?

One of the primary issues is the confusion over the different type of food reactions and different testing methods. Many people assume that they have been effectively screened after performing one type of test. However food allergies, food intolerance, food sensitivities and Coeliac's disease, though often presenting with similar symptoms, are very different conditions.


Each type of food reaction is unique, has a unique immune response (or none at all) and therefore requires a completely different testing approach. So while some people may think that they have been tested for food sensitivities and got an "all clear" - the testing method may not have been appropriate for their particular reaction.


A common example of this is those who have had a test for Coeliac's disease. If they had a negative result they may assume that they do not react to gluten.


However this only confirms that they do not have the unique condition of Coeliac's disease. It is still absolutely possible that this person has a gluten intolerance, Fructan sensitivity (a plant compound found in many foods including most gluten containing grains) or even a wheat allergy.


Many of our patients at Food Intolerance Australia report years of suffering and numerous expensive investigations prior to finally getting the help they deserve. So today we'd like to share the breakdown and defining features of each condition, along with the unique testing procedure, and any other beneficial notes or resources we think could be helpful for you.


Remember, if you are suffering and not sure where to begin, you can always book a consultation with one of our experienced Nutritionists who will help to guide you and can recommend the most appropriate next steps for you.


Food Allergies (IgE reaction)

  • Type of reaction: An immediate immune response to the allergen. Symptoms are typically inflammatory of some kind and can be fatal if not treated. Common reactions include swelling, itching, hives, breathing difficulty and vomiting.

  • Typical response time: Fairly immediate

  • Treatment: Strict life long avoidance of foods and contaminated foods. Possibly requires antihistamine. Individual may be required to carry an epi-pen in case of accidental exposure. Immune therapy is available where drop doses are used to improve immune response to the food, however this is time consuming, costly and not guaranteed to be effective. Life long elimination of the food is the primary recommendation.

  • Food Avoidance: Life long and strict avoidance in most cases, even a crumb could be fatal for some.

  • Severity: Can be life threatening.

  • Testing process: Blood test (RAST testing), available via your GP through medicare. Skin prick testing available with an allergist.

  • NOTE: Coeliac's disease is the exception to the rules of this list. Coeliac's disease is an autoimmune disease which is initiated by an allergic reaction to gluten. We will discuss this condition separately as it requires an individual testing process and has a unique symptom picture.

Food Intolerance (IgG Reaction)

  • Type of reaction: A food intolerance IgG reaction is another allergic reaction, however due being a distinctly different reaction to a food allergy (not life threatening), it is important that this is classified separately in order to prevent confusion.

  • Symptoms: Various reactions can occur with a food intolerance. This may include localised symptoms such as bloating, gas, bowel changes, or may be inflammatory in nature such as skin rashes, hives, eczema etc. Systemic conditions such as headaches, fatigue and depression are also common.

  • Typical response time: Symptoms of food intolerance typically appear between 1-48 hours following digestion.

  • Treatment: Many patients follow the avoidance rule life long as a management for their food intolerance, but this is not necessary. At Food Intolerance Australia we have developed a 3 step process to the treatment of Food Intolerance. Step 1 is to avoid or reduce foods (based on level of reaction). Step 2 is to repair the digestive function and balance the immune system. This allows us to help patients reach Step 3 which is to reintroduce previously problematic foods and regain tolerance.

  • Food avoidance: Temporarily while the underlying problems are being addressed.

  • Severity: Symptoms are debilitating and distressing but not life threatening.

  • Testing process: Blood IgG testing is the only scientifically accepted and accurate way of determining your food intolerances. The blood should be professionally screened for antibodies and analysed for reactions to specific food antigens (the food protein). We believe for guaranteed accuracy the sample should be taken by a trained health professional and appropriately stored. Testing should be completed by specialised pathology laboratories.

  • NOTE: Hair testing is not a viable option for food intolerance testing and consistently shows up with inaccurate results. Our team sent off two hair samples from the same person's head, taken 2 minutes apart. To test the validity of the method we sent them off under different names. We received two very different reports with different reactions and recommendations. There is no evidence to support that hair testing has any ability to determine food intolerance. There are no antibodies present in the hair and hair is easily contaminated during collection, transport etc. We do not recommend or refer for this method.

Food Sensitivity (FODMAP)

  • Type of reaction: Poor absorption and tolerance of certain carbohydrates in foods.

  • Typical symptoms: As this is an issue with digesting the food, rather than an immune response, the reactions will be localised to the digestive system. Primary symptoms incude gas, bloating, diarrhoea, constipation, pain and cramping.

  • Typical response time: Typically 12-48 hours after ingestion.

  • Treatment: The most common treatment is to eliminate all high FODMAP foods initially, and then reintroduce 1 by 1 after a period of resolution (feeling better or, ideally symptom free). However at Food Intolerance Australia we have found many people react to FODMAP foods due to having IgG intolerances which has damaged or distressed the digestive lining. Many of our patients with FODMAP sensitivity have had great results reintroducing their FODMAP foods after following a 3 step process. Step 1: remove or reduce all diagnosed IgG reactions. Step 2: Continue to avoid both IgG reactions and high FODMAP foods for 3 weeks, while also introducing supportive supplements such as probiotics, enzymes and specific amino acids. Step 3: Reintroduce FODMAPs after 3-4 weeks and continue to avoid IgG's for indicated period of time.

  • Food avoidance: Depending on the management. If under the care of the right practitioner food avoidance should be brief as is for the purpose of symptom relief only.

  • Severity: Uncomfortable and annoying, never systemic or life threatening.

  • Testing process: Elimination rechallenge diet seems to be the most reliable for quick relief - our Nutritionists are fully trained and experienced in assisting patients with a healthy (temporary) transition to a low FODMAP diet. An alternative method is the Hydrogen Methane Breath test which assesses the level of gasses in the breath, thought to be eliminated following a reaction from the gut bacteria.

  • Note: According to studies conducted by Monash University, breath testing does not appear to be reliable or produce reproducible results. Therefore at Food Intolerance Australia we generally recommend against breath testing.

Coeliac's Disease

  • Type of reaction: This is an autoimmune reaction which is initiated by gluten allergy. Put simply it is an immune reaction to gluten resulting in destruction of the digestive lining throughout the small intestines. The damage to the intestinal wall (which is responsible for absorption of nutrients) results in numerous nutritional deficiencies and chronic inflammation.

  • Symptoms: Typical symptoms include severe and chronic fatigue, weight loss or difficulty maintaining a healthy weight, nausea diarrhoea or severe constipation, severe bloating (appearing pregnant), gas, mouth sores, hair loss, iron deficiency anaemia, dental abnormalities (such as white spots on the teeth), osteoporosis, depression, dermatitis herpetiformis and neuropathy (unexplained pain, numbness, tingling and weakness). Due to the destruction of the small intestines and the immune imbalance, many patients can form IgG food intolerance to other foods in addition to coeliac's disease, leading to additional symptoms (See food intolerance symptoms discussed above).

  • Typical response time: Typically 2 hours after ingestion with symptoms lasting 24hours or more.1

  • Treatment: Required treatment is life-long strict avoidance of all gluten containing grains. For some it takes many years to recover despite following a strict diet. Some patients are highly senstitive and may experience symptoms after just a few crumbs. Common contamination risks include sharing toasters with others using gluten containing breads, dipping the knife back in the butter after spreading gluten bread and cross contamination in non-specialised restaurants and bakeries.

  • Food avoidance: Life long and very strict. No flexibility at all.

  • Severity: Highly serious condition which can increase the risk of other serious conditions such as Thyroid dysfunction, Osteoporosis, Rheumatoid Arthritis and other autoimmune conditions, Lymphoma.

  • Testing process: Blood test named Coeliac Serology is the first step to determine the likelihood of Coeliac's disease. This test can exclude the possibility but not confirm. If there is a positive result then there is typically endoscopy and colonoscopy to follow which will confirm or deny diagnosis.

  • Note: It is essential that the patient is eating gluten regularly in order to be able to confirm diagnosis. General preparation guidelines for an endoscopic assessment of Coeliac's disease is to consume 4 slices of wheat bread per day for 6 weeks. If you have been gluten free for some time and would like to be screened for Coeliac's disease click here to read about your options for accurate diagnosis.

If you or anyone you know is suffering with any of the symptoms listed on this page, please get in touch with one of our advisers today. Any unexplained health decline should always be investigated as early intervention is key in preventing more serious complications.


Our customer service team is here to answer your queries. We'd love to assist you with finding the most appropriate testing package, or Nutrition support, in order for you to begin your journey to better health through optimum Nutrition.


Food Intolerance Australia

Technical Advisory Team


© 2018 by Food Intolerance Australia

Brought to you by Sydney City Nutritionist

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