One friend is lactose intolerant; another’s son has a milk allergy. Do they mean the same thing?
No, they don’t. While people often use the terms interchangeably in conversation, and while they may even cause similar symptoms, there’s an important difference between food intolerance and food allergy.
Food Allergy
Like other allergic reactions, a food allergy involves your immune system and may affect many different bodily organs at once.
If you have a food allergy, your immune system may go into overdrive when it encounters a certain food protein and trigger an allergic response.
Allergic responses can range from irritating to dangerous. If you’re allergic to something, you might react with itchy skin, swelling, nausea, vomiting or diarrhoea. Or your allergy might trigger anaphylaxis, a serious and potentially deadly allergic reaction that compromises your breathing and cardiovascular system.
Who Gets Food Allergies?
A growing number of people are affected by food allergies, which occur in approximately 5-10% of kids and 2-4% of adults in Australia and New Zealand. There has been a five-fold increase in the numbers of young children (0-4) being admitted to hospital with anaphylaxis due to a food allergy in the last decade.
Food allergies can develop at any point in life but they’re most common in children under the age of 5. See your doctor if you think you or your child has a food allergy. A proper diagnosis enables you to be sure of which foods are safe and means you’re not cutting out some foods unnecessarily.
If your child is allergic to cow’s milk, wheat, egg or soy, they will probably grow out of it. However, allergies to peanuts, tree nuts, sesame and seafood tend to persist in about 75% of affected children. If you develop a food allergy as an adult, it will probably persist.
We can help prevent some food allergies developing by introducing a range of foods to babies around the age of 6 months (but not before 4 months). Research shows that delaying the introduction of some foods until after a baby’s first birthday may make food allergies more likely.
Which Foods May Cause an Allergic Reaction?
If you have kids at childcare or school, you’ll probably have been asked not to pack certain foods – like egg or nuts – in your child’s lunch box to avoid risking the health of classmates with food allergies.
Foods that commonly cause allergic reactions include:
- Peanuts
- Tree nuts (almonds, Brazil nuts, cashews, chestnuts, hazelnuts, hickory nuts, macadamia nuts, pecans, pine nuts, pistachios, walnuts)
- Eggs
- Cow’s milk
- Soy
- Fish
That said, any food could potentially cause an allergic reaction, including fruit.
Food Intolerance
Food intolerance may cause some of the same symptoms as food allergy but the underlying cause is different.
Food intolerances don’t involve your immune system or perhaps involve pathways different to that of allergic reactions. Adverse symptoms is usually limited to your digestive system rather than affecting other parts of your body. Onset of symptoms can be immediate or delayed.
Though it can be distressing, food intolerance is generally less serious than a food allergy since it won’t cause life-threatening symptoms like anaphylaxis. Food intolerance basically means you have trouble tolerating a certain food. You may find you can tolerate small amounts of ‘problem’ foods but that you develop a reaction if you have too much. It’s a bit like managing to put up with an irritating part-time colleague but really struggling to cope when he gets a full-time job in your office.
Who May Have Food Intolerance?
Intolerance to some foods may happen in people who:
- Have Irritable Bowel Syndrome
- Are missing the enzyme that digests dairy, leading to lactose intolerance
- Are sensitive to food additives
- Are dealing with ongoing stress.
If you notice that certain foods cause you trouble, talk to your doctor. Better management of an underlying condition may improve your ability to handle the food or your doctor may recommend methods to aid digestion of certain foods.
Which Foods May Cause Intolerance?
The most common food intolerances are to:
- Dairy – caused by an inability to break down lactose
- Gluten – non-celiac gluten sensitivity may affect up to 13% of people
- Caffeine – some people react badly to this popular stimulant
- Salicylates – these compounds occur naturally in fruits, vegetables, teas, coffee, spices, nuts and honey but trigger uncomfortable symptoms in some people
- Amines – some people can’t break down histamine so must avoid fermented foods
- FODMAPS – in particular people with IBS, who may benefit from a low-FODMAP diet
- Sulfites – these preservatives may affect your enjoyment of wine, beer or dried fruit.
Some foods, eggs and shellfish being good examples, can be associated with both allergy and intolerance reactions. Intolerance to these usually also causes G.I limited symptoms such as vomiting or diarrhoea that can be troublesome, but in contrast to true allergy there is no progression to hives, swelling or breathing difficulties.
People can also be intolerant to artificial food colourings, MSG or aspartame (a sugar substitute).
How Can Allergy Qld Help?
If you think some foods have a bad effect on you or on your child, then we can help. Our experienced allergy clinicians will listen to your experiences and carry out any tests that may be needed. We take you from wondering what’s going on, to understanding why some foods may cause you trouble and knowing how to manage that. Please make an appointment today.
