The good news is that very few people with asthma need to watch out for the foods they eat – apart from following the usual healthy eating advice.
But a small number of people with asthma do have a problem with certain foods triggering their asthma symptoms.
Why can food increase your risk of asthma symptoms?
Food could be an asthma trigger for you because you’re:
- allergic to certain foods. This means you can have an allergic reaction very quickly when you come into contact with your food allergen. And the allergic reaction quickly brings on your asthma symptoms such as wheezing, coughing and difficulty breathing. People with food allergies need to strictly avoid the food they react to.
- sensitive to certain foods, or additives in foods, such as preservatives. Being sensitive to certain foods is not the same as a true allergy, and there’s less clear-cut evidence to show a link to asthma symptoms. But some people with asthma tell us that other kinds of chemicals and ingredients in food products trigger their asthma symptoms.
“Don’t confuse food allergy with food intolerance, which isn’t connected with asthma symptoms,” says Sonia Munde, Head of Helpline.
“Food intolerance can cause symptoms such as stomach ache and bloating hours to days after eating a food. But unlike a true allergy, it isn’t connected to your immune system, and there’s no evidence to suggest it will trigger asthma symptoms.”
How do you know food is one of your asthma triggers?
Although a lot of food allergies start in childhood, you can develop them as an adult too. If you think food might be bringing on your asthma symptoms, but you’re not sure, talk to your GP or asthma nurse soon. Evidence shows that an asthma attack that’s triggered by an allergic reaction to food can be worse, particularly for children with food allergies.
And children with food allergies and asthma are more likely to have high risk allergic reactions to food. This means they’re more likely to have possibly fatal anaphylactic reactions, particularly if their asthma isn’t well controlled.
Your GP can:
- help you work out how to keep a food diary to identify patterns and clues about which foods might be affecting you, or your child. This might include writing down what you eat each day, and any asthma symptoms.
- offer you a referral for skin prick testing to help confirm or rule out any food allergies
- discuss possible food sensitivities with you – which won’t show up in an allergy test
- support you in excluding certain foods or food groups if you need to, to see if symptoms improve
- help you work out if it’s something else, for example acid reflux, that’s making your asthma symptoms worse, rather than an allergy
- update your written asthma action plan and talk about the best ways to deal with any asthma symptoms triggered by food.
How to avoid food triggering asthma symptoms or an asthma attack
If you have a food allergy and asthma there are five things you need to do to cut your risk of an asthma attack.
- Avoid the foods you’re allergic to – especially if you’re at risk of anaphylaxis, which is a life-threatening allergic reaction. “Symptoms can come on extremely quickly,” says Sonia Munde. “People with anaphylaxis need immediate treatment with an auto-injector (EpiPen) and will then need to go to hospital.”
- If you have an auto-injector, keep it with you. Use this immediately if you’re having severe anaphylactic symptoms.
- Keep your asthma reliever inhaler with you at all times, to use if food triggers your asthma symptoms.
- Use your preventer inhaler every day to control inflammation in your airways, meaning you’re less likely to react badly to your asthma triggers. If you have a food allergy, and your asthma’s not well controlled, it increases your risk of any allergic reaction being more severe.
- Talk to your GP or asthma nurse and get your written asthma action plan updated with any new triggers information. It’s important that you manage your asthma and your food allergy together to cut the risk of one making the other worse.
What are the most common food allergies or sensitivities?
Although any kind of food may cause a sensitivity or allergy in some people, there are some food types that are much more likely to cause a problem.
Some of the most common food allergens are: gluten (from wheat and cereal products), shellfish, eggs, milk, tree nuts, peanuts, sesame seeds, and soya.
Some food allergies, such as allergies to milk and eggs, are more common in children.
The most common food sensitivities that can trigger asthma symptoms are:
- Histamine – this is a naturally produced ingredient in some foods such as yogurt, mature cheese, and smoked meats. It’s also found in alcoholic drinks like wine.
- Sulphites – these are used as preservatives in foods such as processed meats and pickled foods. They’re also found in drinks such as wine, beer and cider.
Top tips to cut the risk of food triggering asthma symptoms
- Get ‘free from’ lists from your local supermarket. These will show you all the products free from the allergen you have to avoid.
- Avoid ready meals. If you prepare your own meals you’ll feel more confident about what’s gone into them.
- Plan ahead for eating out. Call ahead to make sure all restaurant staff, from the chef to the kitchen staff, to the waiters know about your allergy.
- Read labels carefully. By law the 14 major allergens (including wheat, milk, nuts and egg) have to be clearly listed in bold on pre-packed manufactured foods throughout the EU. If you’re allergic, or sensitive, to ingredients outside of this list you’ll need to read the whole list through to check. Check and double check because it may not be immediately obvious that your trigger ingredient is in a product.
Need more support and advice?
You can speak to one of our asthma nurse experts by calling 0300 222 5800.
Or chat with them via Whatsapp on 07378 606 728. They can talk to you about all your triggers, including food, and the best ways to stay well with your asthma.
You can also find out more about particular food allergies on the NHS website.
Last updated December 2018
Next review due May 2020