This can make flying a minefield. Not just because traces of nut could be in the air vents of a plane but because of cross-contamination. But that doesn't mean flying with an allergy or flying with someone with an allergy is impossible.
What is an allergy?
An food allergy is when your immune system has a response to a particular food. It's the immune system's job to fight infections, but there can be instances when it becomes primed to respond to foods. This can be triggered when food is eaten and also when inhaled or through touching — the reason airlines make an announcement that nuts will not be served on the flight if someone on board has a nut allergy.
Once someone has come in contact with an allergen, their immune system reacts and symptoms can either appear immediately or take several hours. Symptoms include coughing, vomiting, itchy throat or in the worst case scenario, anaphylactic shock (when the airways narrow and blood pressure drops).
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Someone with an intolerance will have less serious symptoms, such as digestive issues when consuming the food. This can be something like a gluten intolerance. Unlike someone with an allergy, a person living with an intolerance can sometimes get away with eating small amounts of the food and be near others who are consuming it.
If you think you have an allergy, you can get tested at your GP. Intolerances are slightly harder to pinpoint but the gold standard of understanding a food intolerance is to cut the food out for 21 days and then consume a large amount of it on day 22.
You would then wait seven days to see if any symptoms appear. The most common intolerances are gluten, dairy, egg and soy, so it may be worth considering an elimination diet if you are suffering with digestive symptoms.
For those who have an intolerance, you can order a free-from meal ahead of your travel. In fact, it's usually fresher than the general food offering.
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Precautions
It is advised that if you have an allergy you should take measures such as keeping your EpiPen in your hand luggage, labeling medication and informing crew on boarding about what allergy you have.
For U.S. carriers' policies on allergens, visit here.
What else can you do if you are traveling with an intolerance or allergy
Inform the airline: You can call the airline at the time of the booking, at check-in or tell the ground staff and cabin crew and they will accommodate your needs as best they can. Most airlines ask passengers to let them know about their allergies sooner.
Take your own food: Prepare snacks in advance and take them with you on the flight. You will then know what is in your food.
Bring medications and medical documents: The airline may ask you for documents about your allergy and medication. It's a good idea to have this just in case — it could just be a letter from your doctor.
Clean around you when you board: If you have a severe allergy, it may be a good idea to clean around your seat to make sure it's free from allergens.
