Intolerance to Gluten – A Complete Guide

Intolerance to gluten is the most common food sensitivity. Use this page to find out if you are suffering from it, and what to do if you are.

This is an in-depth guide to gluten intolerance and sensitivity. Here are some of the things that you can learn from this page.

If you want an overview of everything there is to know about intolerance to gluten please read on past the table or use the table below to navigate to the part of the page that you are most interested in. On the other hand, if all you really want is a concise guide to a certain aspect of living with an intolerance to gluten just click the links on the bottom right of this page to be taken to the right place.

What is Gluten Intolerance?


Gluten intolerance is sensitivity to some of the proteins found in wheat and other grains. People with this kind of sensitivity are sensitive to what is called true gluten.

Gluten free crackersTrue gluten is a composite of two proteins, gliadin and glutenin that are joined together with starch. Other grains such as corn contain gluten but it is a different form that many people’s bodies may tolerate.

However, it is important to realise that some people can be sensitive to all forms of gluten even those found in corn. This is called true gluten intolerance or sensitivity. (For more information visit our section about what grains you can eat if you are gluten sensitive)

Is an intolerance to gluten the same as celiac disease?


The answer to whether celiac or celiac disease is the same as gluten intolerance is it depends on which professional you speak to. The closest I could get to a logical answer was the one I found at the University of Chicago Celiac disease centre page. They say:

“We use “gluten intolerance” when referring to the entire category of gluten issues: celiac disease, non-celiac gluten sensitivity and wheat allergy. Celiac disease is an inherited autoimmune disorder that affects the digestive process of the small intestine.”

“Non-celiac gluten sensitivity” (what many call “intolerance to gluten”) causes the body to mount a stress response (often GI symptoms) different from the immunological response that occurs in those who have celiac disease (which most often causes intestinal tissue damage).”

That is as clear as it gets, but what we do know for sure is that avoiding gluten is better for the health of someone who is sensitive to gluten than continuing to eat it.

Gluten Sensitivity is Different from Wheat Intolerance


Wheat intolerance and gluten sensitivity are two different conditions. Those with non-celiac gluten sensitivity cannot eat wheat because it contains gluten, which is the protein that gives dough made with wheat flour its elasticity. They are also not able to eat other grains that contain true gluten for example barley and rye.

However, someone who is just wheat intolerant may be able to happily eat barley and rye without any adverse effects. This is because their body is sensitive to proteins that are only found in wheat, but not in other grains.

The causes of sensitivity to gluten


Studies carried out in America show that around 15% of the offspring of someone with an intolerance of gluten has the condition. This suggests that gluten intolerance is inherited. In those people, the symptoms of gluten sensitivity manifest themselves at an early stage in life.

However, some people find themselves developing issues with gluten later in life. Exactly why that happens is not fully understood.

It may be that the condition has been present all of the time, but the symptoms were too mild to notice. However, it may also be that a health or stress event triggered the symptoms. For example, some women discover that their body is sensitive to gluten after they give birth.

The symptoms of gluten sensitivity and intolerance


The symptoms of gluten intolerance vary considerably from person to person. Some people experience only one or two symptoms, others experience the full spectrum.

When the symptoms are mild or intermittent it can be quite hard to spot gluten sensitivity.

Here are the main symptoms:

Digestive issues related to gluten sensitivity


Bloating and gas


Constipation (most common in children who are gluten intolerant)

Skin symptoms

Keratosis Pilaris (chicken skin) appearing on the arms or thighs. This looks like permanent goose bumps it can be red and inflamed and may itch.

Less common symptoms of gluten intolerance



Brain fog

Feeling tired after eating gluten

Dizziness and lightheadedness

Poor balance

Unexplained infertility

The early onset of hormone issues such as PMS or PCOS

Man with a headacheMigraines


Joint pain and inflammation


Mood swings and depression

Some research indicates that the presence of an autoimmune disease can indicate that a person is sensitive to gluten. This includes diseases like arthritis, lupus, MS, psoriasis and scleroderma.

Foods to avoid if you are gluten intolerant


The list of foods that contain gluten is long, very long. Here is an overview of the main culprits:


Wheat and wheat germ

Rye and rye based products

Bulgar wheatEars of barley



Graham flour

Most forms of matzo


Spelt flour


Malt beerMalt and most malt flavouring

Commercial soups both tinned and dry

Commercial bullion and broths

Many cold cuts, in particular, dry sausage products like pepperoni

French fries are often dusted with flour before freezing, so contain gluten

Many of the major fast food retailers also dust their chips with flour, so need to be avoided

Most processed cheese (e.g., Velveeta)

Mayonnaise and sauces that contain mayonnaise

Most varieties of ketchup

Malt vinegar

Soy sauce and teriyaki sauces

Most salad dressings

Imitation crab-meat, bacon and other processed meats

Egg substitutes


SausagesSausages of all kinds

Most meatballs because they contain breadcrumbs

Most breaded products

Non-dairy creamer

Tempura vegetables and seafood

Gravy powders

Many marinades

Canned baked beans


Commercially prepared chocolate milk

Breaded foods

Some fruit fillings and puddings

Ice cream

Root beer

Communion wafers

Energy bars

The majority of trail mixes




Instant hot drinks

Some flavoured coffees and teas

Vodka bottleMost brands of vodka

Wine coolers


Veggie burgers

Roasted nuts that are coated

The majority of beers

Some oat products because of the risk of cross-contamination

Oat bran (unless it is certified gluten free)


Hidden Gluten in Meat


Cold cuts that are factory processed

Wieners and hot dogs made with cereal fillers

Sausages made with cereal fillers

Honeyed hams some of which are coated with a starch-based coating

Breaded meats lick chicken Kiev

Meatballs made with bread or cereal filler

Meat or fish that has been marinated or basted with a grain based product 

Hidden gluten in common ingredients

The following ingredients also contain gluten:

Avenal saliva cyclodextrinEars of oats

Brown rice syrup


Fermented grain extract

Hordeum distichon

Hordeum vulgare


Hydrolyzed malt extract or vegetable protein (HVP)

Hydrolyzed soy protein


Modified food starch

Phytosphingosine extract

Samino peptide complex

Secale cereale


Modified food starch

Textured vegetable protein

Hydrolyzed plant protein

Hydrolyzed vegetable protein

Hydrogenated Starch which is also called Hydrolysate

Hydroxypropylated Starch

Pregelatinized starch

Vegetable gum

Vegetable protein

Extenders and binders




Artificial flavors – especially smoky ones

Caramel coloring and flavoring

Gravies – check out both thickening agents and liquid base.

Baking powder (commonly contains grain – wheat or corn)

Triticum aestivum

Triticum vulgare

Tocopherol/vitamin E

Yeast extract

Surprising foods that contain gluten


Candy dusted with wheat flour

Many canned soups

Processed cheeses

Chocolate that has had malt flavouring added

Some brands of stock cubes

Dip and dry sauce mix

Ice cream and frozen yogurts made with starch products

All dairy products – if you are very sensitive to gluten dairy products made with cow’s milk from grain fed cattle can cause a reaction, but this is normally only a problem for those with a full-blown gluten allergy.

Some non-dairy creamers

3 bottles of soy sauceSoy Sauce


Instant coffees and teas, which may contain cereal products such as barley

Mayonnaise that contains grain based thickeners or vinegar

Mustard made from powder

Oil and foods fried in oil that is corn based may cause issues with those who are sensitive to the gluten in corn

Sour cream – May contain modified food starch of indeterminate source.

Dry roasted nuts & honey-roasted nuts basted in a cereal-based flavouring

Vitamins and supplements may contain gluten

What grains can gluten intolerant people eat?


For the most part, I follow and share the advice given by the medical community to the letter. However, every now and again I come across a new piece of research, which makes me stop and think that maybe the current best practice within the mainstream medical community is not 100% correct.

This happened when I started to research which grains those with gluten issues should be eating. I found a piece that pointed out that several of the grains nutritionists say are OK for those with gluten sensitivity to eat actually contain high levels of gluten.

The advice was that many with sensitivity to gluten could potentially benefit from cutting out these grains:








Rice (wild rice contains virtually no gluten, so it is fine)

Many health authorities include corn, oats, sorgum and rice on the list of grains that it is all right for those with gluten sensitivity to eat.

Perhaps the most sensible approach is to eliminate all of the above grains and re-introduce rice, millet, oats, sorgum and finally corn one at a time. If your symptoms return, you know that your body cannot tolerate those particular forms of gluten as well as the ones found in wheat, rye and barley.

Gluten intolerance testing

If you suspect that gluten does not agree with you. it is very important to be tested by a professional rather than simply eliminate gluten from your diet. This is because there is a chance that you could have celiac disease. You need to eliminate celiac disease as the underlying cause of symptoms when you eat gluten-laden foods.

This is because celiac disease does long term damage to your digestive system. Over time, this damage can have a serious affect on your health.

The diagnosis of celiac disease is not easy


This is because a damaged intestine cannot extract important nutrients from your food. When you consider that between 92 and 97% of the nutrients from your food is absorbed in the intestines it is vital that this organ functions properly.

The longer you go un-diagnosed the worse the damage to your intestines will be.

To determine whether your inability to eat gluten is caused by celiac disease you need to see a doctor. You cannot test for it at home. For the test to be accurate, you need to have been eating gluten as part of your regular diet prior to the test.

The first stage of celiac coeliac diseasedisease testing is to take a blood test that looks for the presence of celiac antibodies. If they are present, a biopsy will be taken from your gut to confirm the disease. Sometimes the blood test will be negative for celiac or celiac antibodies, but symptoms persist. In that situation, your doctor will usually send you for a gut biopsy.

If both tests are negative, the chances are you are intolerant of gluten or wheat. In other words, you have non-celiac gluten intolerance.

What is involved in non-celiac gluten sensitivity testing?


Currently, there is no biological marker for non-celiac gluten intolerance. However, your medical history of you and your family will be covered as part of the diagnostic process. This is because if your parents had issues with gluten there is a heightened risk that you will too.

In addition, you may be offered a radioallergosorbic blood test (RAST test). When it comes to gluten intolerance, some allergists prefer to use an Immunocap test (CAP-RAST) this brand of test gives the medical professional more data to work with. Some physicians also offer skin prick testing for gluten. Unfortunately, these tests are not 100% reliable, but they can diagnose some cases of food intolerance.

Alternative allergists may also use challenge testing or electrodermal screening, but these intolerance diagnostic approaches are not recognised by all in the profession. They are known to produce a lot of false positive results in particular electrodermal testing.

For gluten intolerance by far the most reliable testing method is an elimination diet. Should you suspect your body reacts badly to gluten simply eliminate it from your diet for three or four weeks then re-introduce it. If your symptoms ease when you are not eating gluten and begin to reappear when you start eating gluten again you are gluten intolerant.

Because gluten is a big protein, it can take years to purge your body of it. This means that not all of your symptoms will clear straight away it will take time for your body to remove all elements of gluten and then time for any damage to heal.

The connection between chronic diseases and gluten sensitivity


We have already mentioned that if your inability to eat gluten turns out to be celiac disease the impact on your general health is high. The fact your body cannot efficiently absorb the nutrients from your food means that over time you can become quite ill.

Gluten free recipes


If you are looking for gluten free recipes we have a growing database on this site. Just click on the gluten intolerance tab in the main menu, and choose the recipes that interest you from the drop down menu.