Managing Food Allergies
What causes food allergies to specific foods has been researched for many years. When somebody has a reaction to food, that individual's immune system sees that particular food product – for example peanut – and thinks that it is something harmful for the body.This is because people with food allergies have been exposed to that food in a way that made the immune system think that this was something harmful rather than something innocuous that wouldn't cause any problem.When the individual then has contact with that food – say peanut – by either by eating it, some goes into their eye or if it's rubbed onto some broken skin, they could get an allergic reaction. This is because their immune system has already recognised that this is something that is foreign and needs to be dealt with.
Allergies, like most chronic conditions, are caused by a combination of genetic and environmental factors. More recently there has been a breakthrough in understanding that if a child has an inflamed disrupted skin barrier in the first year of life, and they are potentially exposed to allergenic foods through the skin, this causes the immune system to pick up on that food as something that is harmful to the body.
Going back to our previous example of peanut, the child then develops an allergic response to peanut and the next time the child is exposed to peanut the body starts to have an allergic response.
A top tip for those suffering from food allergies would be to get a proper allergy diagnosis so that they know exactly what it is that they are allergic to. For example, somebody could have a reaction to scrambled egg, and think that they're allergic to the egg, but it could be the milk that was used to prepare the scrambled egg. So, it's very important to get some proper allergy testing which can be done by skin test or a blood test using a specific IgE testing.Once you have a formal allergy diagnosis, then you need to have a good understanding of the types of allergic reactions you might have. You could get an immediate allergy reaction which would cause hives and swelling and potentially anaphylaxis. Or it could be a delayed allergy reaction, in which case it would cause allergy symptoms later, a few hours after eating the food, and that could be skin rashes or eczema or gut issues.You need to know how to identify the types of reactions that you're going to have and how to manage them. If you are experiencing a food allergic reaction, the first thing would be to stop eating the food that's causing the issue. You need to know how to manage the food allergy, including having a proper emergency plan, particularly for those with immediate food allergies that will need the right medication.Then you need to ensure that you know how to avoid that food once you know what you are allergic to, such as by reading food labels properly. Telling people that you have an allergy is a good idea, so that they don't give it to you inadvertently. It's also important to make sure that if you have a food allergy – for example to cow’s milk – and you avoid cow's milk in your diet, and that you make sure your diet has enough in the way of calcium, vitamin D and iodine. This is because you may lack those nutrients if you're not having cow's milk, so it's important to look into that to make sure that nutritionally your diet is complete. This is even more important when managing food allergies for children who are still growing and in breastfeeding mothers who have increased calcium requirements.
Whether the body can be trained in getting rid of food allergies is something that has been intensely researched in the last five to ten years. We know that with immunotherapy for inhalant allergens– for example for pollen allergies and house dust mite allergy – can have injections, take tablets or sprays under the tongue, which can help to retrain the immune system to be less allergic to those inhalant allergies.When it comes to foods, in terms of certain foods that are naturally outgrown – for example most children outgrow their egg and milk allergy – there are things that can be done to help that individual outgrow their milk and egg allergy more quickly. This can be done by introducing baked forms of that food into the diet. Please that this does need to be done under medical supervision, rather than just at home. There are certain food allergies that are more persistent, meaning that once a child has that allergy, usually they remain allergic for the rest of their lives. Examples include that only 20% of children outgrow their peanut allergy and only 10% of children outgrow tree nut allergies such as cashew and walnut allergy.The question whether immunotherapy (also known as desensitisation) actually ‘gets rid’ of food allergy is really important because a lot of the media has been portraying this food allergy treatment as a cure. What the studies have shown is that it does not cure the food allergy but it does reduce the risk of accidental reactions to the food and reduces severity of allergic reaction if a reaction does occur. The person doing the food allergy desensitisation or oral immunotherapy program needs to continue taking that food every day for the rest of their lives. This means that it's not something that would be defined as a ‘cure’. A cure would be that you no longer have to think about eating that food, you can just eat it whenever you want. Rather than a cure, we say it will make that individual ‘bite proof’. An example would be if they are peanut allergic and had some peanut by mistake in a restaurant, they would be much less likely to have an allergic reaction. Also if they were to have an allergic reaction, studies have shown that it is much more likely to be a milder allergic reaction than if they were not taking this treatment.
When it comes to food allergy reactions, you have two types of food allergy – immediate allergy reaction and delayed allergy reaction. Immediate food allergy causes hives and swelling, itchy, runny nose, vomiting, and in the most severe cases could lead to problems with the airway, breathing or consciousness.
For immediate food allergies symptoms – for example a skin rash hives, or swelling – then using a non-sedating antihistamine such as cetirizine is a good treatment. These can be bought over the counter for children over the age of two years, because it is licensed from that age. However, for children under the age of two, this would need to be prescribed.
In terms of more severe allergic symptoms such as problems with airway, breathing, or circulation, this is something that needs to be treated with adrenaline. This is also known as an anaphylactic reaction (a life-threatening allergic reaction). Adrenaline auto injectors are not available over the counter so they do need to be prescribed. This emergency medication is the gold standard treatment for anaphylaxis and if it is used you must always call 999 to get emergency services and say the word ‘anaphylaxis’.
It's so important when managing food allergies for you or your child, that you see somebody who is able to diagnose the allergy and any related allergies properly, and give you a personalised emergency plan to help you to recognise allergic symptoms and know how to manage them. Read more about how we can help with food allergy management.
When it comes to delayed allergies, the symptoms may be an eczema flare or maybe some gastrointestinal issues. For an eczema flare, many good moisturisers are available over the counter and the National Eczema Society has some great information about this. If the skin becomes very red and inflamed there are some topical steroids that can be applied. Some of these are available over the counter, and some need to be prescribed.
When it comes to the gut, and symptoms associated with the gut, it's very much about removing the offending food from the diet to see if that improves the symptoms. Sometimes some people can use a non-sedating antihistamine, like cetirizine which may help, but the main treatment would be to avoid the foods causing the symptoms.
Want to know more Allergic Rhinitis Facts? Read the full article on All you need to know about allergic rhinitis by consultant paediatric allergist Dr Helen Brough.
- Hives resembling a nettle rash
- Swelling around the mouth or eyes, which can extend to different parts of the body
- Vomiting or having loose stools
- Sneezing or rubbing the nose and/or eyes
- Rarely, anaphylaxis (problems breathing)
- Persistent cough or swollen tongue
- Trouble breathing or wheezing
- Impact on blood pressure, leading to dizziness or sudden sleepiness
- Paleness or appearing floppy
- Flare-up of redness on the skin
- Dry, itchy patches resembling eczema
- Appearance of small dots under the skin
- Gastrointestinal issues, particularly severe colic, stomach pains, loose stools, constipation, or gastroesophageal reflux (more common in young babies)
- Allergen Avoidance: Understanding how to read allergy labels on packaged foods to identify potential allergens and ensure safe consumption.
- Dealing with "May Contain" Labels: Learning how to assess and manage the risks associated with products that may contain traces of the allergenic food.
- Eating away from home: Guidance on navigating restaurants, including communicating dietary needs to staff, asking what ingredients are in the foods when there is either a formal, buffet style or family style service, and making informed choices.
- Handling Takeaways: Understanding how to navigate food options from takeout establishments with no food labels while ensuring allergen safety.
- Recognising Allergic Reactions: Educating parents on identifying the signs and symptoms of an allergic reaction in their child.
- Response to Symptoms: Providing clear instructions on how to address different types of allergic reaction symptoms after a child eats, including when and how to administer appropriate medications.
- Emergency Action Plan: Developing a personalised emergency plan that outlines steps to be taken in case of severe allergic reactions, including the use of epinephrine auto-injectors and seeking immediate medical attention.
- Nutritional Alternatives: Ensuring suitable substitutes and alternatives to the allergenic food are available to maintain proper nutrition and support the child's growth and development.
- In the event of a life threatening severe allergic reaction that may impact the airway, breathing, or consciousness (anaphylaxis), intramuscular adrenaline is considered the gold standard treatment.
- Parents must first ensure their child is in the appropriate position. If the child is experiencing consciousness issues, they should lie down with their legs elevated. If the child is experiencing airway or breathing difficulties, they can sit up but should not be fully upright.
- It is crucial to administer the adrenaline auto-injector immediately (training on proper usage is provided in my clinic). Following administration, the child should remain in the same position, and someone should call emergency services at 999, explicitly stating "anaphylaxis."