Food Allergy Symptoms

Experiencing an adverse reaction to a food can be scary and confusing. It’s important to understand food allergy symptoms and the difference between allergies and intolerances, so you can find the trigger and prevent it happening again.

There are a wide range of symptoms – some immediate and obvious and others more subtle or misunderstood. Firstly it’s important to understand different types of allergies and whether your reaction is from an allergy or intolerance.

Immediate food allergy symptoms

If you have an immediate food allergy (also known as an IGE allergy) you will experience symptoms soon after eating. The most common symptom is a food allergy rash, known as hives, which is raised, red and itchy. This usually occurs on the face but can spread across the body.

You might also experience an itchy mouth, swelling of the lips, eyes or face, or stomach cramps and vomiting. In babies or young children, you might notice they are very distressed, stop feeding or try to scratch at their tongues.

In severe reactions, an immediate allergy can affect your breathing and circulation with wheezing, swollen throat or collapse. Most immediate food allergy symptoms can be treated with antihistamines but for more severe reactions, also known as anaphylaxis, you need to call 999 as it is a medical emergency.

Delayed food allergy symptoms

Delayed food allergy symptoms can start showing after a few hours, or up to 72 hours later so sometimes it can be difficult to know what food has triggered them.

Symptoms can include stomach ache, diarrhoea, reflux, colic or eczema flares.

Food intolerance symptoms

Food intolerances do not involve the immune system like allergies do. However, they can still cause some uncomfortable and difficult symptoms. Intolerances are more likely to show up as bloating, stomach discomfort, sleep disturbances or changes in bowel movements.

The first step to decoding your symptoms is to keep a record of any foods and reactions. If you have experienced immediate symptoms, stop eating that food until you have spoken to your GP, who may refer you for tests. With delayed allergies or intolerances it can sometimes take longer to notice patterns and know which foods to eliminate. A dietician can help support you with any eliminations.

You can learn more about food allergies in my book Living With Allergies.