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A gluten-free diet is imperative for people with coeliac disease. However, it can also be life-changing for those who suffer from a gluten intolerance.
The gluten-free diet excludes foods which contain gluten, a protein found in the grains wheat, barley and rye. People who have coeliac disease must exclude gluten from their diet for life. For others with an intolerance to gluten, the eating plan may help to ease some of their symptoms. Various studies, including this 2018 research, found that a gluten-free diet is the only effective treatment for coeliac disease. This is because gluten can damage the gut of people with the condition.
Cristian Costas Batlle, a specialist gastroenterology dietitian, says: “Coeliac disease is a multisystem autoimmune condition, where gluten causes damage to the small intestine when eaten. “For people with coeliac disease, gluten can cause digestive and non-digestive symptoms. This is because the condition affects other systems in the body. So if gluten is not removed from the diet properly it can cause long-term complications.”
However, people with a gluten intolerance, which can cause symptoms like abdominal pain, constipation and headaches, may be able to tolerate small amounts of gluten in moderation.
What is a gluten-free diet?
A gluten-free diet is an eating plan which removes all foods containing gluten. Gluten is a protein found in the grains wheat, barley and rye. A gluten-free diet may be adopted by people for health reasons including coeliac disease and gluten intolerance. British Society of Gastroenterology guidelines found that for those with coeliac disease, a lifelong and strict gluten-free diet is the only option to manage the condition. However people with an intolerance to gluten often also adopt the diet in order to ease some of their symptoms.
Nowadays awareness around gluten has improved significantly and products containing gluten must be clearly labelled. There are also many gluten-free products available to buy in the supermarket.
Specialist gastroenterology dietitian Cristian Costas Batlle, who treats patients at City Dietitians, told us: “A gluten-free diet is really important for people with coeliac disease as it is the only available options people have to heal their gut. There are no medications that can stop gluten from causing gut damage. So people need to follow a strict gluten-free diet for life in order to keep the gut healthy. This also helps them to avoid long-term complications associated with damage to the small intestine. If the diet is not followed there is an increased risk of mortality. Plus, a greater chance of developing conditions like cancer and osteoporosis.”
For many people starting a gluten-free diet may feel quite daunting. This is often because there are so many products which must be avoided or carefully checked for ingredients.
Benefits of a gluten-free diet
The main benefit of a gluten-free diet is good health for people with coeliac disease. This is because their immune system reacts to even the smallest amount of gluten and can damage their gut. However, people with an intolerance to gluten can also feel the benefits too of fewer uncomfortable symptoms.
For people with coeliac disease: the only option is to follow a gluten-free diet.
Removing gluten from their meals and snacks helps patients to avoid painful symptoms. These include diarrhoea, steatorrhea (fatty stools), weight loss, abdominal pain, bloating, constipation, fatigue and iron deficiency.
For people with gluten intolerance, a gluten-free diet can help to reduce symptoms including abdominal pain, constipation and headaches.
However, while there are certainly benefits to be gained from a gluten-free diet, researchers have warned that people should not remove it from their meals unnecessarily (if not coeliac). This is because many gluten-containing products also have important nutrients in them. This study found that gluten-free processed grain products are often lower in fibre, iron, zinc and potassium than those which contain gluten.
So cutting gluten entirely from your diet should only be done with careful consideration. If you are unsure about what you can and can’t eat it is worth speaking to a dietitian or nutritionist. This may help you to narrow down what is causing your symptoms.
Coeliac disease vs gluten intolerance
Coeliac disease and gluten intolerance are quite different health conditions, although sufferers may experience some of the same symptoms. This is because coeliac disease is an autoimmune disorder and must be medically diagnosed. For people with the disease, the immune system has been reacting to gluten and damaging their gut. Over time this damage prevents the absorption of nutrients from food and can lead to long-term health problems. Someone with gluten intolerance, however, may have similar symptoms to celiac disease, but will not experience damage to their gut.
The main differences between coeliac and gluten intolerance are:
- Caused by the immune system reacting to gluten and damaging the gut
- Must avoid gluten in order to allow the gut to heal in order to start absorbing nutrients from their diet
- Symptoms: diarrhoea, steatorrhea (fatty stools), weight loss, abdominal pain, bloating, constipation, fatigue, iron deficiency
- Some people with coeliac disease cannot eat oats as they contain a protein called avenin, which is similar to gluten
- Caused by non-coeliac gluten sensitivity or a wheat allergy
- Avoiding gluten may help to avoid/reduce symptoms. However small amounts of gluten may be tolerated.
- Symptoms: diarrhoea, abdominal pain, bloating, constipation, rash, headache, breathing difficulties
Cristian, a specialist gastroenterology dietitian, told us: “Gluten intolerance doesn’t actually exist as a medical diagnosis. When people use this term it’s usually because they feel they have symptoms when they eat gluten-containing foods. However, it’s always important to dig deeper. The first thing to do is get tested for coeliac disease, to ensure it’s not that. This is because symptoms can be similar. Also, gluten is only one of the components in wheat that people can have symptoms with. Some people that think they have ‘gluten intolerance’ could have a wheat allergy. Or, alternatively, could be reacting to other components in wheat like fructans, due to having irritable bowel syndrome.
“Finally some people have what we call non-coeliac gluten or wheat sensitivity. This is a medically-recognised condition, once coeliac disease and wheat allergy have been ruled out.”
For these reasons, it is worth seeking help from a registered nutritionist or dietician to get to the bottom of the issue. This will ensure that you do not give up gluten unnecessarily, as this can lead to additional problems.
This research found that while there is evidence that shows gluten avoidance may be beneficial for some patients with gastrointestinal symptoms, such as irritable bowel syndrome, other data shows that removing gluten from your diet when it is not necessary can actually lead to problems. These potential harms include possible nutritional deficiencies and financial costs. Plus, the restricted diet and lifestyle can have negative social and psychological implications.
Naturally gluten-free foods
While removing gluten from your diet may feel tricky at first, there are plenty of naturally gluten-free foods. These include lots of fresh foods, non-processed meats and certain grains.
Fresh foods that can be part of a gluten-free diet:
- All fruits
- All vegetables (including potatoes)
- Beans and legumes
- Most low-fat dairy products
- Non-processed meat, poultry and fish
- Seeds and nuts
Grains, starches or flours that can be part of a gluten-free diet:
- Ancient grains, including amaranth, millet, teff, sorghum
- Gluten-free flours, such as rice, soy, corn, potato and bean flours
Foods that contain gluten
While sometimes it’s obvious which foods contain gluten, at other times it can be hidden. That’s why it’s vital to read the ingredients of a product unless its label can confirm that it is ‘gluten-free’. This is because wheat or gluten is often added to processed foods as a thickener, binding agent, flavouring or colouring.
Registered dietitian Cristian told us: “People may find gluten unexpectedly in products like frozen chips, certain sauces (like HP sauce), crisps, sweets and chocolates, as well as drinks like supermarket cola or Vimto.”
Here are some foods that contain gluten and some that are worth watching out for:
Natural sources of gluten:
- Wheat (including its different varieties: durum, einkorn, emmer, Kamut, spelt)
- Triticale (a cross between wheat and rye)
- Oats, in some cases
- Wheat flours and derivatives (enriched flour, farina, farro, milled wheat, graham flour, self-rising flour or phosphate flour, semolina, wheatberries)
Food and drink commonly containing gluten:
- Beer, ale, porter, stout (usually contain barley)
- Bread, breadcrumbs, croutons, pastries
- Bulgur wheat
- Cereals and granola
- Chips and fries
- Gravies and sauces (including soy sauce)
- Imitation meat products or seafood
- Processed meat
- Vegetables in sauce
How to check food labels
Learning how to check food labels is very important for following a gluten-free diet. This is because it may not always be obvious if a product contains gluten. In the UK ‘gluten-free’ can only be used on food which contains 20 parts per million or less of gluten. All pre-packaged food labels must also list clearly any ingredients containing gluten, no matter how little of it is used.
Registered dietician Cristian explains why: “Unfortunately for people with coeliac disease, less than a crumb of gluten is enough to cause damage to the gut. So it’s important to check for ingredients like wheat, rye and barley which all have gluten in them. You should also make sure oats are labelled gluten-free.”
Here’s how to check food labels for a gluten-free diet:
- Look for a gluten-free label or a crossed-out grain symbol
- Check the ingredient list for wheat, barley, rye, oats
- Check for ‘may contain’ warnings for gluten or wheat
Coeliac UK also has an app which enables you to scan labels on food in supermarkets. This can help you to decide if they are suitable for your diet.
Cristian adds: “People with coeliac disease should also check for cross-contamination on food labels. This is to ensure food in the packet hasn’t come into contact with gluten in the cooking or manufacturing process. As even these small amounts can still cause damage to the gut.”
Nowadays many supermarkets have dedicated areas for gluten-free substitute foods.
Advice for eating gluten-free in restaurants
The best advice for eating gluten-free in restaurants is to ensure that you communicate your needs with staff. This may include calling the venue in advance of your visit to discuss the gluten-free options available. This is also a chance to ask how the food is prepared, in order to prevent any cross-contamination. In addition, make sure you explain your dietary needs to the person serving you when you arrive.
Foods to be particularly careful about when eating in restaurants:
- Sauces and gravy
- Breadcrumbs used as a coating
- Stock cubes and powders
- Oils used for frying
- Fried products cooked in the same oil as other food which contain gluten
Many restaurants will now include gluten-free symbols on their menus, which should help you to order. You can also request that your meal is prepared using different pans and utensils to avoid cross-contamination.
Coeliac UK has a gluten-free symbol that venues can display to show they are accredited by the organisation. This means they follow strict procedures in food handling and ingredient use to ensure a safe gluten-free experience. Plus it also has a list of venues available on its website and app, which offer gluten-free options.
Gluten-free diet: a dietitian’s verdict
Registered dietitian Cristian Costas Batlle says: “I think the gluten-free diet is still seen as a fad by many people. However, we must understand that for people with coeliac disease it’s the only choice they have to treat their condition. It is a lifelong restrictive diet which can be very challenging to follow due to having to constantly avoid cross-contamination.
“It also has its risks if not applied properly. This is because we need to make sure the diet is adequate and balanced once gluten is removed. This is why I think people should always get tested for coeliac disease before removing gluten from the diet. We need to make sure only people who need this treatment are restricting their diet.
“Currently our testing for coeliac disease only works with accuracy when people are on a gluten-containing diet. Deciding that you have ‘gluten intolerance’ and just removing gluten from your diet could lead to being misdiagnosed. Having undiagnosed coeliac disease that is not treated properly can then cause more problems further down the line.”
Where to seek further advice
If you think that you may have coeliac disease you must take some tests in order to be diagnosed. During this time it is important that you continue to eat gluten, otherwise, the tests may be inaccurate. You should then do the following:
- Take an online assessment with Coeliac UK to see whether you may have coeliac disease. Then make an appointment to see your GP.
- Have a blood test to check for antibodies which can indicate coeliac disease. (Although worth noting that it is possible to have a negative test and still have coeliac disease.)
- If the test is positive or your GP suspects coeliac disease, you will be referred to a gastroenterologist (gut specialist). They may then recommend a gut biopsy or further blood tests to help with diagnosis.
More information is available from Coeliac UK, which has more than 60 groups around the UK. Each one offers advice and support to people with coeliac disease and those living gluten-free.
In America, the Celiac Disease Foundation also supports those living with the condition and fundraises for further research.
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