Food intolerances
A food intolerance is a physical reaction that occurs after eating certain foods, which can make you feel unwell. It is not usually serious, but it may have an impact on your quality of life.
Read on to learn more about them and their symptoms, causes, common types, diagnosis and treatment options.
What is a food intolerance?
A food intolerance is when your body reacts to certain foods and causes symptoms. You experience symptoms because you struggle to digest these foods. This reaction does not involve your immune system and the symptoms usually affect your digestive system. They can occur every time soon after you eat the triggering food.
Food intolerance vs food allergy
Both food intolerances and food allergies can cause people to have symptoms in response to specific foods, but they are completely different conditions.
A food allergy occurs when a certain food causes a biochemical reaction that involves your immune system. It results in an exaggerated response, with symptoms that can affect the whole body. A food allergy may be more severe than a food intolerance and can be life-threatening for some people.
Food intolerances are far more common than food allergies and never serious or life threatening.
Symptoms
You may have all or some of these common symptoms if you have a food intolerance and you eat a triggering food. They can develop a few hours after eating the triggering food and might last a few hours or days. Symptoms of a food intolerance will be different for each person and each reaction.
The symptoms can include:
- Tummy pain
- Bloating
- Diarrhoea
- Passing gas
You may have other symptoms that outside your digestive system, such as headaches, feeling sick, feeling tired, or joint pain.
Causes
If your body finds it difficult to digest certain foods, it can cause a food intolerance. Having a condition like IBS (irritable bowel syndrome) can also make you more prone to becoming sensitive to food.
Sometimes your body does not have the specific enzyme needed to digest certain foods. For example, people with lactose intolerance do not have the enzyme required to digest a type of sugar, called lactose, which is found in dairy products.
Common types of food intolerances
Food intolerances are triggered by some types of foods. Lactose intolerance is the most common intolerance in the UK.
Other types of food intolerances include:
- Gluten intolerance, which occurs when your body finds it difficult to digest wheat, rye and barley. These ingredients are in foods like bread or pasta.
- Histamine intolerance, which occurs in response to things like wine and cheese
- Alcohol intolerance
- Caffeine intolerance, where things like coffee, tea or some fizzy drinks can cause symptoms
Other ingredients people may be intolerant to include sulphites, found in some canned food, beer and wine, or salicylates, which are found in some fruits and vegetables. Some people are intolerant to monosodium glutamate (MSG), which can be found in cured meats and other savoury foods.
Diagnosis
A food intolerance can be difficult to diagnose, and it can cause similar symptoms to other conditions.
Keeping a food and symptoms diary to track the foods you eat and your reactions can help you determine what the trigger may be. You should record:
- What you eat and drink
- When it was consumed
- Your stress levels throughout the day
- The time and duration of all your symptoms
If you have symptoms of a food intolerance, it is important to speak to your doctor and you may need a referral to a specialist. At Digestive Health UK, we will discuss your symptoms with you and review your medical history. You may also need a physical examination. Our gastroenterologists and dieticians will work closely together to help us determine the possible cause of your symptoms.
Food intolerance tests
There are a few ways we can diagnose a food intolerance. We might ask you to follow a special diet, called an elimination diet, to help determine which food is causing your intolerance. We’ll ask you to avoid the suspected trigger for a few weeks to see if your symptoms improve. Afterwards, you can start eating the food again to see if your symptoms return. If your symptoms come back, you may have a food intolerance. Our dieticians can help guide you through this process.
You may also need some tests to confirm your diagnosis and some intolerances have specific tests. For example, we can diagnose lactose intolerance using a breath test. In this test, you will drink a liquid with lactose in it and then breathe into a container every 30 minutes, for a few hours. If you have a lactose intolerance, high levels of hydrogen will be picked up in your breath.
There are some commercial food intolerance tests available. However, we would recommend getting your diagnosis from a specialist instead, as there is limited medical evidence to support the tests’ accuracy and results.
Watch our video FAQs on food intolerance tests here: Food intolerance FAQs
Treatment
Your treatment plan will be developed with you and our specialists, including a dietician.
There are various aspects involved in treating a food intolerance. This includes dietary therapies and/ or medication, depending on your intolerance and if you have an underlying condition.
Dietary therapies can include avoiding the triggering food or limiting the amount you eat. If you do not know what your food intolerance is, we may recommend a low FODMAP diet. This is where you temporarily restrict certain foods that contain specific carbohydrates for around four to eight weeks. These foods are slowly reintroduced to your diet to determine what you are reacting to.
We might recommend medication to help you with the digestion of certain foods or treat your underlying condition, if you have one. Some people may be able to eat small amounts of their triggering food, or prevent a reaction, by taking certain medication.
For example, if you are lactose intolerant, you should eat lactose-free dairy products. You may also be able to take lactase enzymes before eating foods with lactose in to assist how they are digested and broken down. We might also recommend medications to manage any symptoms, such as antacids or anti-diarrhoeal medicine.
If you have a vitamin deficiency because of your food intolerance, we may treat you with supplements.
At Digestive Health UK, we partner with City Dieticians to offer treatment options and dietary therapies that are best suited to you. We will guide you through your treatment plan and help you on your journey to managing your food intolerance.
Book an appointment
If you have gastrointestinal symptoms, or think you may have a food intolerance, our expert team can help you identify the cause, find a diagnosis and develop a treatment plan that is right for you.
Book an appointment to find out more about how we can help you.