Are you among the 17 per cent of Aussies who avoid certain foods due to an allergy or intolerance? Before you self-diagnose, read what our experts have to say.
You only have to host a kid’s birthday party, or invite friends and family over for a meal, to discover how common food allergies are. An adverse reaction to food can be a bewildering experience — firstly, trying to work out what triggers your symptoms, and then learning how to avoid the offending foods. This can also affect your social life — for example, finding safe options on the menu when you eat out, or planning a dinner and catering for someone who has special dietary requirements.
The good news is, over time, you can manage a food allergy or intolerance more easily — you might even discover delicious substitutes. Here’s our guide to finding out why you might be reacting to certain foods, starting with three of the main reasons for adverse reactions — and ways to ensure you don’t miss out on essential nutrients.
1. Food allergy
Food allergy occurs in around one in 20 children and about 2 per cent of adults, according to the Australasian Society of Clinical Immunology and Allergy (ASCIA). These allergies occur when your body’s immune system reacts unusually to the food you eat and attacks it by releasing histamine. The most common allergy trigger foods are egg, cow’s milk, peanuts, tree nuts, seafood, sesame, soy, fish and wheat.
If you’re allergic to a food, the symptoms will usually appear within 30 minutes to two hours after eating. Symptoms vary, from mild itchiness, hives and rashes through to vomiting and serious anaphylactic reactions, requiring immediate medical help. ASCIA recommends that you ask your doctor to complete an Action Plan for Allergic Reactions (available from allergy.org.au) to ensure a swift response in the event of a severe reaction.
What to avoid
Quite simply, you should try to avoid whatever causes the reaction. “The most important thing to remember about the symptoms of food allergies is that they will occur every time the suspected food is eaten,” says clinical immunologist and allergist, Dr Marianne Empson. “If you don’t eat the food, you won’t react.”
This can be harder than it seems, as the offending food could be an ingredient in a variety of processed foods. A specialist dietitian can teach you how you can prevent occurrences and ensure your diet is nutritionally balanced.
If you suspect you have a food allergy, it’s important to have it investigated by your doctor — not to self-diagnose. Your GP might recommend that you see a specialist to undergo an allergy test.
2. Food intolerance
Food intolerances can produce symptoms that are similar to food allergies, but the cause is quite different. Usually food intolerances affect the digestive system, and trigger reactions by irritating nerve endings in your skin, airways, nervous system and gut.
Some common reasons for food intolerance include:
Lack of an enzyme to properly digest the food, such as lactase deficiency, which is responsible for lactose intolerance.
A reaction by individuals to a specific group of carbohydrates, such as FODMAPs.
Sensitivity to certain food chemicals or preservatives, such as salicylates or amines.
The symptoms are usually digestive problems associated with Irritable Bowel Syndrome, such as bloating, stomach cramps and diarrhoea. They tend to come on slowly, long after you have eaten, making diagnosis difficult. If you suspect food intolerance, it is a good idea to keep a food and symptom diary to help your doctor pinpoint what the issue might be, so they can refer you to the right specialist.
What to avoid
Not surprisingly, this depends on what’s causing the intolerance. For instance, lactose intolerance occurs when someone can’t digest the lactose which is present in milk and other dairy products. Three out of four people with Irritable Bowel Syndrome (IBS) notice improvements when they follow a low-FODMAP diet, says Dr Sue Shepherd, Advanced Accredited Practising Dietitian and clinical researcher. To learn more, visit shepherdworks.com.au.
Why doesn’t cow’s milk like me?
A food allergy to cow’s milk protein
Difficulty digesting lactose, the natural sugar in milk (lactose intolerance)
Sensitivity to the grass the cow ate.
3. Coeliac disease
Coeliac disease, pronounced ‘seel-ee-ak’, is not actually an allergy. Instead, it’s an autoimmune disease where a person’s immune system reacts abnormally to gluten, the protein found in wheat, barley, oats and rye. An estimated one in 70 people is living with coeliac disease, according to Coeliac Australia, but four out of five remain undiagnosed.
“There are a variety of symptoms, including abdominal pain, bloating and flatulence, but they can also include fatigue, headache or mouth ulcers,” explains Sally Tobin, communications manager at Coeliac Australia. “An absence of these symptoms is also possible.” If you suspect you have coeliac disease, you can learn your risk from an online assessment at coeliac.org.au/assess. Then, if indicated by the results, make an appointment to see your GP for a proper diagnosis.
What to avoid
Currently, there is no cure for coeliac disease and you need to follow a strict gluten-free diet for life. This rules out many foods, including bread, cakes, cereals and pasta, but also several less obvious products that contain wheat flour, such as soy sauce, seasonings and sausages.
Why doesn’t bread like me?
Undiagnosed coeliac disease, causing you to react to gluten
Food allergy to wheat
Food intolerance to the fructans in wheat (oligosaccharides, which are the ‘O’ in FODMAP)
Sensitivity to the type of preservative used in the bread (such as propionate 282).
If you are avoiding certain foods, you may be missing out on essential nutrients, so it’s important to make sure you’re getting them elsewhere.
Don’t miss out on diabetes-friendly cereal fibre. Boost your intake with:
Nuts, seeds and legumes
Don’t miss out on heart-healthy monounsaturated fats. Boost your intake with:
Don’t miss out on brain-boosting omega-3 fats. Boost your intake with”
Don’t miss out on bone-strengthening calcium. Boost your intake with:
Salmon (with bones)
Calcium-fortified soy milk
NOTE: If you’re allergic to soy, you may have problems with these foods too, so check with your doctor or dietitian.
Don’t miss out on hunger-busting plant proteins. Boost your intake with?
Cooked legumes (chickpeas, lentils, split peas and lupin)
Why so sensitive?
A study of one-year-olds in Melbourne found that more than one in 10 had a food allergy. In an effort to pinpoint the causes of the high rates of food allergies in babies, the following theories are being studied extensively.
Over-cleanliness: Our obsession with cleanliness reduces exposure to different types of bacteria that help build our immune systems.
Changed diets: We’re eating a much greater variety of foods than we used to, including more processed and packaged foods, meaning there are more potential allergens in our diets.
Delayed introduction: Protecting infants from eating potentially allergenic foods, like nuts, might actually be inhibiting their bodies’ ability to tolerate them.
Environmental factors: We all have increased exposure to chemicals and pollution in our day-to-day lives.
Vitamin D deficiency: Babies born and breastfed over the winter months have a higher incidence of allergy, suggesting vitamin D is a factor.