Allergy vs. intolerance: What is the difference?
As mentioned in our Managing food allergies in babies & children article , the key difference between a food allergy and a food intolerance is that a food allergy involves the immune system reacting to a usually harmless substance. These may include certain foods, pollen, animal dander or dust mites. They can also include certain medications or insect bites.
On the other hand, food intolerances are less specific and cover a wide range of adverse food reactions which do not involve the immune system. Whilst these can be uncomfortable and may impact general health and wellbeing, they do not involve life threatening reactions to food like anaphylaxis.
Food intolerances may instead cause symptoms such as digestive discomfort, bloating, wind, diarrhoea, rashes, mouth ulcers and headaches by a number of other means which are unrelated to the immune system. These symptoms may not always appear immediately after eating the problematic food, which can also make it tricky to pinpoint what the trigger foods are. It may also take several occurrences of eating a food high in a particular offending food component to “push it over the edge” and contribute to a symptom, again, making it difficult to identify what food or foods are causing the symptoms for your child.
Some of the most common types of food intolerances in children include:
- Intolerances to food chemicals such as amines, glutamates and salicylates - these naturally occurring chemicals found in foods can irritate nerve endings at different sites in the body causing symptoms.
- Food additive intolerance affects a small number of children. The common food additives that may contribute to symptoms include tartrazine and preservatives such as sulphites and benzoates that you may find in packaged foods and dried fruit.
- Cow’s milk protein intolerance, sometimes accompanied by soy milk protein intolerance - this typically occurs before 1 year of age in both breastfed and formula-fed babies. However, most children outgrow this intolerance by the time they reach 5 years of age.
Lactose intolerance in children
Generally speaking, lactose intolerance is uncommon amongst babies. Breast milk is naturally rich in the milk sugar, lactose. Lactose intolerance in children typically is due to a lack of the enzyme responsible for digesting this milk sugar called lactase, which can be due to genetics or can also develop over time. Lactose intolerance is not the same as cow’s milk protein intolerance.
New research was published in 2019 which analysed the results of a clinical trial involving 75 Chinese children aged between 5 and 6 years with mild to moderate milk discomfort or lactose intolerance (confirmed via a urinary galactose test). The study reported that replacing conventional milk with a2 Milk™ "reduced gastrointestinal symptoms associated with milk intolerance" in many subjects. More research is needed to understand the broader implications of these results.
a2 Milk™ contains the same amount of lactose as found in conventional cow’s milk. This means that if your child has lactose intolerance as confirmed by your healthcare professional, then it will be necessary to exercise the same precautions when introducing your child to a2 Milk™ as you would in relation to any other cows’ milk. The Australian Dietary Guidelines suggest that up to 250mL cows’ milk may be well tolerated by lactose intolerant individuals if consumed with other foods and spread over the day.
However, it is important to bear in mind that all cow’s milk, including a2 Milk™, should be excluded from your child’s diet if your child has been diagnosed with a cow’s milk allergy or cow’s milk protein intolerance. These are different to lactose intolerance and A1 protein sensitivity, which is explained further below.
Understanding A1 protein intolerance
Research over the years demonstrates that some people who experience digestive discomfort when drinking conventional cows’ milk find a2 Milk™ easier on digestion. This is because the A1 beta-casein protein that is found in conventional milk is digested differently to A2 beta-casein protein. There is a growing body of evidence that supports the unique benefits of consuming milk from cows that naturally produce only the A2 beta-casein protein type, like a2 Milk™.
Diagnosing food intolerances
Diagnosing food intolerances does not require a blood test, so please be aware of online test kits promising insights from your child’s blood, urine or hair to determine food intolerances.
Your healthcare professional may want to rule out an allergy first with some of the tests discussed in the Managing food allergies in babies & children article. Depending on the results of these tests, your healthcare professional may then discuss with you the possibility of your child having a food intolerance by exploring potential dietary triggers and referring you to an Accredited Practicing Dietitian . Your dietitian can then assist you further in understanding what your child’s trigger foods are and at what amounts your child can tolerate them.
Managing food intolerance in babies & children
Generally, getting to the bottom of a food intolerance for your child may involve eliminating the suspected offending food for a period of time, and then systematically reintroducing, also known as “challenging”, that food in increasing amounts to determine what your child’s unique “threshold” is to that particular food or food component.
From there, your dietitian will guide you through how to reintroduce more foods into your child’s diet whilst minimising the chances of an adverse food reaction to maximise nutrition but minimise symptoms.
An elimination diet is certainly not meant to be a lifelong diet. Rather, it is a tool to be used under the strict supervision of a dietitian to help you understand your child’s intolerances and ultimately liberalise their diet whilst continuing to avoid or minimise severe or frequent symptoms that can interfere with their quality of life.
The good news is that, unlike food allergens, foods that your child may be intolerant to do not necessarily need to be completely excluded in all cases.
For example, even if you have lactose intolerance, you may be able to consume certain types of dairy foods in limited quantities. Research has shown that many lactose intolerant individuals can tolerate up to 250mL of lactose-containing milk per day when consumed with other foods and spread over the day. Hard cheeses such as cheddar and parmesan cheese are very low in lactose, and many lactose intolerant individuals have found that they can tolerate lactose-containing yoghurt too.
The important distinction between food allergies and food intolerances is that, whilst the symptoms associated with a food intolerance are uncomfortable, they are generally not dangerous to your child’s health.
Top tips for managing food intolerances in children
- Unless your child’s food intolerance is caused by a common allergen, it may not be immediately apparent on the product labelling whether the product contains a potentially offending food or food component. Working with a dietitian is key to helping you become confident with reading product labels and ingredient lists so that you can navigate your child’s food intolerances on a daily basis.
- Ensure that you do not keep your child on a restricted diet for a long period of time, as this can increase their risk of developing a nutritional deficiency and can cause them to miss out unnecessarily on key nutrients they need each day to grow, develop and thrive!
- There will be times where you introduce foods to your child which exceed your child’s tolerance threshold, or their tolerance thresholds may even change over time, causing their symptoms to re-emerge – if this happens, don’t be too hard on yourself! The symptoms will almost always resolve on their own within a short period of time and despite the discomfort a food intolerance reaction can cause, they will not put your child’s health and wellbeing at risk.
- Speak with your local dietitian with an interest in childhood food intolerances
Article written by accredited practicing dietitian & nutritionist, Stefanie Valakas.