Gluten free diets have gained a lot of headlines, both positive and negative, and are often dismissed as a fad, but for those with coeliac (celiac) disease, or non-coeliac gluten sensitivity (NCGS), following a gluten free diet is a medical necessity.
Gluten is the collective term for a type of resilient, stretchy protein found in some cereals such as wheat, rye, and barley. Some people are sensitive to gluten and develop a range of symptoms that vary from coeliac disease to general aches, weakness and feeling tired all the time. Following a gluten free diet can sometimes resolve non-specific symptoms that are difficult to pin down to any particular cause. There is a printable gluten free food list at the end of this post.
What is gluten protein
Gluten is a storage protein found in grains. All grains contain these storage proteins, but the specific ones found in wheat, barley and rye can trigger immune reactions in susceptible people when they are eaten. Some people with gluten sensitivity also develop symptoms when eating oatmeal, although many types of oat are now bred to be gluten-free and can be tolerated.
Gluten is an enormous composite protein which forms a strong, stretchy mesh of smaller proteins linked together. These proteins include long, springy strands of glutenin and shorter, rounder protein polypeptides which bind these strands together. Glutenin gives gluten its elasticity, while the smaller binding molecules gives it is strength. The binding proteins in gluten from different cereals are slightly different in their amino acid sequences and have different names:
- In wheat the small gluten molecule is gliadin
- In rye it is secalin
- In barley it’s hordein
- In oats it is avenin
- In maize it is zein.
The fact that gluten is both strong and stretchy allow it to trap bubbles of gas and expand during bread-making so the dough rises.
Some people develop immune reactions against gluten proteins, especially against the smaller gliadin protein. These immune reactions involve white blood cells (lymphocytes) and may include the development of anti-gliadin antibodies.
In some people, gluten sensitivity causes immune cells to mistake part of the bowel lining as foreign so they mount an attack. This attack causes an inflammatory reaction in which the lower part of the small intestines (jejunum) becomes infiltrated with lymphocytes and the intestinal wall withers (atrophies) to cause coeliac (or celiac) disease. Coeliac disease is also known as gluten-sensitive enteropathy and was once more commonly known as sprue.
Gluten and coeliac disease
Coeliac disease results from a severe hypersensitivity to the smaller gliadin proteins found in wheat gluten, although why this reaction happens remains unknown. It may be due to a direct toxic effect of gluten on the bowel wall in people who have inherited certain genes, or may result from immune reactions triggered by previous exposure to an infection such as rotavirus. Sometimes coeliac disease develops after bacterial food poisoning (gastroenteritis), pregnancy, surgery, or severe stress.
The intestinal symptoms of coeliac (celiac) disease include:
- Abdominal pain, which can be severe
- Diarrhoea, which is typically pale, smelly, greasy and float due to poor fat absorption
- Noisy bowel movements (borborygmi)
- Acid reflux and heartburn
- Weight loss
- Weakness and fatigue
Infants may experience vomiting, a swollen belly, poor appetite, muscle wasting, poor growth and failure to thrive due to an inability to absorb the vitamins, minerals, energy and building blocks needed for growth.
The non-intestinal symptoms of coeliac disease can include:
- Weakened bones (osteopenia, osteoporosis) due to poor absorption of nutrients
- Neurological symptoms such as pins and needles, numbness, poor co-ordination, attention deficit, learning disorders and even seizures
- Mouth ulcers
- An itchy, blistering skin rash (dermatitis herpetiformis) which typically appears on the elbows, knees, torso, buttocks and scalp
- Hormone imbalances – including delayed puberty, loss of periods and reduced fertility.
Those who develop the skin symptoms often do not to develop the abdominal symptoms of coeliac disease.
The symptoms of coeliac disease are brought on by exposure to dietary gluten and resolve when following a gluten free diet. Someone who is sensitive to the gliadin form of gluten is often sensitive to the types of small gluten molecules found in other grains, too, especially the secalin found in rye and the hordein in barley, because of the similar amino acid chains they contain.
People with gluten sensitivity are less likely to react to the avenin gluten in oats, but everyone is different depending on the way their immune cells respond and type of antibodies they make.
How common is coeliac disease?
Gluten sensitivity can be present from birth and appear after weaning onto gluten-containing foods, but most often it develops later in life.
If symptoms develop in childhood, the sufferer is often shorter than expected due to poor absorption of nutrients from the gut. In adults, the condition is commonly diagnosed in the third to fourth decade and affects more females than males.
Coeliac disease is diagnosed by antibody testing (for IgA anti-tissue transglutaminase antibody or IgA TTG). Sometimes a biopsy of the intestinal wall is also needed to confirm the diagnosis by identifying the typical infiltration by white blood cells (lymphocytes) and flattening of the jejunal wall and loss of the tiny, finger-like projections (villi) that absorb nutrients and fat from the diet.
Coeliac disease affects around 1 in every 100 people and often runs in families. Coeliac disease is twice as prevalent in Ireland, Italy, Sweden and Finland, but the highest rates are found among the Sahrawi of Africa, where 1 in 17 people are affected.
Coeliac disease is more common in people with other autoimmune conditions such as type 1 diabetes, ulcerative colitis and autoimmune thyroid disease.
If you think you could have gluten sensitivity, see your doctor for tests to confirm whether or not you have coeliac disease.
It’s estimated that for every person with coeliac disease, however, there are at least another six or seven with a non-coeliac gluten sensitivity so, even if coeliac disease testing is negative, you could still have a non-coeliac gluten sensitivity.
Non-coeliac gluten sensitivity (NCGS)
Non-coeliac gluten sensitivity was first recognised in 1980 and now appears to be more common than coeliac disease. Non-coeliac gluten sensitivity or NCGS is believed to affect between 7% and 35% of the population – a wide range that depends on how it is defined. NCGS is diagnosed if eating a food containing gluten causes unpleasant symptoms but is not associated with the classic intestinal wall changes associated with coeliac disease.
Because the symptoms of NCGS vary from person to person, it is classed as a syndrome, or cluster of symptoms, which can include a combination of intestinal and non-intestinal symptoms, or many only include non-intestinal symptoms such as tiredness and a rash.
The intestinal symptoms of NCGS are similar to those of coeliac disease itself but are less severe, and may include:
- abdominal pain
- mouth ulcers
- anal fissures
The non-intestinal symptoms of NCGS can include:
- lack of wellbeing
- foggy thoughts
- joint and muscle pains
- eczema-like skin rashes
- recurrent mouth ulcers.
In children, non-coeliac gluten sensitivity has also been linked with attention deficit disorder, aggression, autistic spectrum behaviours and asthma.
Other symptoms that have been linked with NCHGS, include depression, nasal congestion, irritable bladder, ingrown hairs, period problems, sleep difficulties, mood swings, hallucinations and schizophrenia.
What causes NCGS?
The exact protein that triggers non-coeliac gluten sensitivity has not yet been identified, and may not be gluten itself. Grains contain proteins other than gluten which might cause non-gluten sensitivity reactions. Some experts believe NCGS is caused by sensitivity to proteins called amylase-trypsin inhibitors.
There is increasing evidence of a link between the gut and the brain. One possibility is that some of these symptoms are due to increased intestinal permeability (leaky gut syndrome) which might allow gluten peptides or other wheat-derived proteins to enter the bloodstream and reach the brain. A popular hypothesis is that these wheat-derived proteins either trigger inflammation within the brain, or affect nerve signalling chemicals and communication between brain cells to cause neurological and emotional symptoms.
Gluten free diet
The treatment of both coeliac disease and non-coeliac gluten sensitivity is to follow a gluten-free diet.
When you have confirmed coeliac disease, following a gluten-free diet usually produces a rapid improvement in symptoms within a few weeks and must be followed for life.
When you have NCGS, it is unknown if long-term, strict avoidance of all gluten-related products is needed. In some people, symptoms of NCGS are transient and resolve on their own, so that you may be able to tolerate gluten-containing foods again after a period of abstinence.
The good news is that gluten exposure is something you can control, and removing gluten from your diet can dramatically impact your health and quality of life whether you have coeliac disease or non-coeliac gluten sensitivity.
Gluten-free diet food list
A gluten-free diet allows you to eat a wide variety of nutritious foods, including the following naturally gluten free foods. You can find a gluten free food list printable at the end of this post.
Type Of Food
|Grains||Rice, tapioca, sago, arrowroot, buckwheat (which despite its name is not related to wheat), millet, hempseed, teff, maize, corn and cornflour
|Wheat, wheat bran, rye, barley, spelt, kamut, einkorn wheat, emmer (farro), semolina, some oatmeals, and products made from them eg bread, pastry, pasta, couscous, cakes, biscuits, breakfast cereals unless declared gluten-free|
|Vegetables||All fresh vegetables, beans, peas, lentils
|Canned vegetables or vegetables in ready meals if they contain certain emulsifiers, preservatives, thickening agents, stabilizers, or starch eg potato croquettes|
|Fruits, nuts, seeds||All fresh fruit, nuts and seeds||Fruit pie fillings that contain thickening agents or starch|
|Dairy products||Eggs, milk, cream, unprocessed cheese, natural and some fruit yoghurts||Yoghurt containing muesli or grains, yogurt thickened with starch, processed cheese that contains thickening agents|
|Meat||All fresh, unprocessed meat, poultry or offal
|Meat pies, beefburgers, sausages, scotch eggs, pork pies, tinned and other processed meats that contain starch|
|Fish||All plain (uncoated) fresh fish eg salmon, tuna, mackerel, cod, prawns, lobster, crab, mussels
|Processed fish products, preserved fish, fish in batter, fish in bread crumbs, fishcakes, fish fingers|
|Fats||Butter, pure olive oil, nut oils and seed oils that do not contain additives.||Margarine and vegetable oils may contain additives with gluten|
|Drinks||Tea, freshly ground coffee, fruit juice, wine, non-barley beer, spirits
|Barley water, instant coffee, ready-made coffee or cocoa from drinks machines, beer and stout made from barley, malted night-time drinks|
|Other||Fresh herbs and spices||Most stock cubes, gravy mixes, ready meals and processed foods of any kind|
Gluten is alcohol soluble and can be removed from wheat to produce a gluten-free wheat starch, so many gluten free foods are available, such as gluten-free foods such as bread, crispbread, biscuits, cakes, breakfast cereals and pasta.
Gluten-free flours include: soya flour, potato flour, pea flour, rice flour, gram flour
Gluten is added to some cosmetic products but rarely listed in the ingredients. Although gluten is not absorbed through the skin, when used in lipstick or foundation small amounts can be ingested. If your intestinal or skin symptoms persist, despite following a gluten-free diet, use cosmetics labelled as gluten-free.
Wheat starch is sometimes added to medicines, but it is of pharmaceutical quality and considered gluten-free. If in doubt, talk to a pharmacist.
Gluten foods to avoid
When following a gluten free diet, avoid foods that include ordinary (gluten-containing) wheat, rye, barley and flours/products made from these.
Avoid any food labelled as containing wheat, gluten or gliadin. Wheat is often present in products such as soups, stock-cubes and dessert mixes.
Avoid foods containing Flour starch, Wheat flour, Wheat starch, Food starch, Edible starch, Modified starch, Gelatinised starch, Vegetable starch, Cereal filler, Cereal binder, Cereal protein, Malt, Rye, Hydrolysed vegetable protein, Kamut, Natural flavouring, Soy Sauce, Gum, Triticale, Spelt, Rusk, Barley unless they are declared gluten-free. Wheat can be processed to render it gluten-free by washing the gluten out of flour.
Gluten-free is not the same as wheat-free
A product can be wheat-free and not gluten-free. A product can be gluten-free and not wheat-free. There are however, products which are both gluten-free and wheat-free.
Take a multivitamin supplement
If you have coeliac disease, or are following a restricted diet because of non-coeliac gluten sensitivity or wheat sensitivity, it is important to take a multivitamin and mineral supplement. This will help to guard against the nutritional deficiencies that can result from poor nutrient absorption or avoiding certain foods. Check your supplement is gluten-free. Click here for my review of the Best Multivitamin Supplements.
Some people with non-coeliac gluten sensitivity find that taking digestive enzymes, which break down wheat proteins and gluten, can reduce their symptoms. If you have symptoms due to NCGS a product supplying gluten protease, cellulase and amylase may help. NB If you have coeliac disease it is important to continue avoiding gluten-containing foods.
Aloe vera has a soothing effect on the bowel. Select products declared aloin-free to avoid a laxative action.
Click here for: Gluten free food list printable