What is a gluten-free diet?
Following a gluten-free diet involves eliminating all gluten-containing foods and beverages. Gluten-containing grains, such as barley, rye, and wheat, are ingredients present in many staple foods included in the typical Western diet. On average, North Americans consume about 5 to 20 g of gluten per day, but for certain individuals, ingesting gluten may lead to gastrointestinal (GI) upset and damage to the GI tract.
What is gluten?
“Gluten” is the general term for a group of proteins that are found in certain grains, including barley, rye, and wheat. In nature, gluten proteins promote germination and seedling growth.
In culinary applications, gluten is widely used to modify the quality, texture, flavor, and moisture content of foods.
Wheat is one of the most common sources of gluten, mainly consisting of the proteins glutenin and gliadin. Proteins similar in structure to gliadin have also been found to trigger gluten-related GI upset, including hordein in barley, secalin in rye, and avenin in oats.
What are gluten-free products?
Baked goods made with wheat flour, such as breads and pastries, are well-known sources of gluten; however, gluten is also commonly used as an additive, often as a thickener or gelling agent, in processed foods including candies, dressings, sauces, meats, and vegetarian meat substitutes. Since gluten is ubiquitous in the food supply and consumer demand for gluten-free products has continued to grow, many brands now distinguish when their product is gluten- free. Gluten-free labeling is voluntary, but if a brand chooses to label its product as “gluten-free,” certain regulations must be followed.
The U.S. Food and Drug Administration (FDA) has set specific criteria in order to ensure that foods that are labeled as “gluten-free” are safe for consumption by those with gluten intolerances. According to the FDA, a gluten-free labeled food or beverage must have less than 20 ppm (parts per million) of gluten, the lowest consistently detectable amount. Gluten-free foods can be:
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Naturally gluten-free (e.g., apple, poultry)
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Made from a gluten-free grain (e.g., corn, rice)
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Made from a gluten-containing grain that has been processed to remove gluten (e.g., wheat starch)
Products labeled “free of gluten,” “no gluten,” and “without gluten” must also abide by the FDA’s criteria; however, claims such as “gluten-friendly,” “no gluten ingredients,” and “wheat-free” do not fall under the FDAs ruling and, therefore, may not be gluten-free.
Gluten-related label claims
|
Claim |
Meaning |
|
Gluten-free |
Applies only to packaged foods |
|
Gluten-friendly |
Often used in restaurants to describe a gluten-free menu item that was prepared in a kitchen that also uses gluten-containing foods No oversight to guarantee the product is gluten-free |
|
Wheat-free |
Not monitored by the FDA; however, all foods containing wheat must list wheat clearly on the ingredients label No guarantee the product is gluten-free |
|
May contain gluten |
The food or product may contain traces of gluten Often found on products that are manufactured using shared equipment, increasing the possibility of cross-contamination |
Who should follow the gluten-free diet?
Certain health conditions warrant adherence to a gluten-free diet. Depending on the condition, a lifelong gluten-free diet may be necessary.
Celiac disease
Celiac disease, also known as celiac sprue or gluten-sensitive enteropathy, is a chronic, autoimmune condition in which the immune system abnormally responds to gluten resulting in damage to the small intestine. Common symptoms of celiac disease include abdominal pain, bloating, and diarrhea.
Patients with celiac disease must adopt a strict, lifelong gluten-free diet, as well as avoid all gluten-containing personal care products, supplements, and medications. Living gluten-free is necessary to reverse and avoid further damage to the small intestine, as well as mitigate some of the risks associated with long-term, unaddressed celiac disease. Research indicates that it takes approximately three to six months of following a gluten-free diet for the small intestine to heal in children.
For adults, this healing process can take approximately two to three years.
Did you know?
Celiac disease affects approximately 1% of the global population.
The small intestine is lined with tiny, finger-like structures called villi. The villi are responsible for facilitating nutrient absorption from food. In undiagnosed and/or unaddressed celiac disease, the villi become damaged and flattened, lessening their ability to absorb nutrients. This can lead to various negative health consequences such as nutrient deficiencies, certain cancers (e.g., intestinal cancer, intestinal lymphoma), infertility, neurological disorders, and osteoporosis.
Research suggests that individuals with celiac disease are more likely to be diagnosed with other autoimmune conditions, such as:
• Addison’s disease: a condition affecting the functioning of the adrenal glands and hormone production
• Autoimmune thyroid diseases: Hashimoto’s thyroiditis (a cause of hypothyroidism) and Grave’s disease (a cause of hyperthyroidism)
• Type 1 diabetes mellitus: a condition that occurs when the pancreas produces little to no insulin
• Dermatitis herpetiformis: a chronic skin condition characterized by itchy bumps or blisters, particularly occurring on the forearms near the elbows, knees, and buttocks and worsened when gluten is ingested
• Psoriasis: a chronic skin condition that accelerates the growth cycle of skin cells, leading to thick red skin and silvery patches on the elbows, knees, scalp, face, hands, and feet
• Rheumatoid arthritis: a chronic inflammatory condition that causes swollen, painful joints
• Systemic lupus erythematosus (lupus): an autoimmune condition affecting various organs such as the skin, joints, kidneys, and brain
Similarly, individuals with these autoimmune conditions may be more likely to develop celiac disease. Implementation of a gluten-free diet may help slow the progression of these autoimmune conditions, especially if started at an early stage.
Gluten sensitivity and intolerance
Gluten sensitivity, sometimes referred to as gluten intolerance or non-celiac gluten sensitivity,
is a disorder affecting an individual’s ability to tolerate gluten. Gluten sensitivity is not well understood and researchers are actively investigating to gain a better understanding of this condition. Patients with a gluten sensitivity may experience similar signs and symptoms to celiac disease; however, consuming gluten while gluten sensitive doesn’t appear to cause the same damaging effects to the small intestine or long-term health issues when ingested.
Wheat allergy
Wheat allergy is an allergic response to foods containing wheat. Wheat allergy is most common in children, and about 65% of children outgrow their allergy by adulthood; however, some people may continue to experience this condition into adulthood. Individuals with a wheat allergy don’t necessarily need to follow a gluten-free diet, but should strictly follow a wheat-free diet. This means that they can still safely consume other gluten-containing foods such as rye and barley.
If you have a wheat allergy, you should avoid wheat-containing foods as well as personal care products that contain wheat. In some cases, simply inhaling wheat flour can trigger an allergic response. Depending on the severity of the allergy, some patients may experience anaphylaxis,
a severe, life-threatening allergic response, in response to allergen exposure, requiring immediate treatment with epinephrine (adrenaline) and medical attention.
Gluten-free grains
| Gluten-containing grains |
Gluten-free grains and pseudograins |
|
Barley, Bulgar, Durum, Farro, Kamut, Rye, Semolina, Spelt, Triticale, Wheat |
Amaranth, Buckwheat, Corn, |
*Oats may contain traces of gluten and may not be tolerated by certain individuals.
Precautions
A gluten-free diet is considered safe for most individuals; however, it’s important to be aware of the various vitamins, minerals, and fiber found in gluten-containing grains that will need to be obtained through other dietary sources. Consider the following nutrients and dietary components when following a gluten-free diet.
Alternate sources of dietary components found in gluten-containing grains
|
Dietary component of concern |
Dietary sources |
|
Fiber |
Gluten-free whole grains, fruits, vegetables, beans, legumes, nuts, seeds |
|
Folate |
Beans, legumes, asparagus, eggs, leafy greens |
|
Iron |
Soy, beans, legumes, dark leafy greens, beef, chicken, turkey, oysters |
|
Niacin |
Fish, beef, chicken, turkey, beans, legumes, nuts, seeds |
|
Riboflavin |
Eggs, organ meats, lean meats, milk, green vegetables (e.g., asparagus, broccoli, spinach) |
|
Thiamin |
Meat, poultry, pork, seafood, eggs, yogurt, beans, legumes, soy, nuts, seeds |
It’s also important to note that just because a food or beverage is gluten-free, that doesn’t necessarily mean that it’s a healthy choice. Many store-bought gluten-free products, such as cakes, cookies, and crackers, are highly processed and often contain just as much sodium, sugar, fat, and artificial ingredients as their gluten-containing alternatives.
Remember that many foods are naturally gluten-free
If you’re new to the gluten-free diet and you’re feeling overwhelmed by all of the ingredients you need to avoid, keep in mind that most whole foods are naturally gluten- free. You can freely enjoy many foods, including fruits, vegetables, beans, legumes, gluten-free grains, nuts, seeds, meat, poultry, fish, seafood, eggs, and dairy products,
as long as they are prepared without cross-contamination or added gluten- containing ingredients.
Watch out for non-food sources of gluten
Gluten isn’t only found in foods; it can also be found in many products you use regularly such as medications, supplements, and personal care products (e.g., toothpaste,
lip balm, lotion, soap, shampoo). When following a gluten-free diet, particularly if you have celiac disease or a wheat allergy, use extra caution and read product labels thoroughly to ensure that they’re gluten-free.
Hidden sources of gluten
Checking the ingredients label is the simplest way to recognize a gluten-free product. Don’t see wheat, barley, or rye? Gluten could be in the ingredients list under a different name. Below are common gluten-containing ingredients.
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Bread crumbs
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Brewer’s yeast
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Bulgur
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Cereal extract
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Club wheat
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Couscous
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Cracker meal
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Durum
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Einkorn
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Emmer
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Farina
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Farro
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Flour (all-purpose, bread, cake,high-gluten, high-protein, instant, pastry, self-rising, soft wheat, steel ground, stone ground, whole wheat )
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Freekeh
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Graham
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Hydrolyzed wheat protein
• Kamut
• Malt (malt extract, malt flavoring, malt syrup, malt vinegar)
• Seitan
• Semolina
• Spelt
• Sprouted wheat
• Starch (gelatinized starch,modified starch, modified food starch, vegetable starch)
• Triticale
• Vegetable protein
• Vital wheat gluten
• Wheat berries
• Wheat bran hydrolysate • Wheat germ oil
• Wheat grass
• Wheat protein isolate
Frequently asked questions (FAQ)
What does the term “gluten-free” mean?
The FDA defines “gluten-free” as a food or product that is naturally gluten-free, does not contain a gluten-containing ingredient, or contains a gluten-containing grain that has been processed to remove gluten. All products labeled “gluten-free” should contain less than 20 ppm of gluten, a level generally recognized as tolerable by individuals with gluten sensitivities.
Is wheat the same as gluten?
Gluten is a complex protein found in wheat grains and other gluten-containing grains such as barley and rye. A product claiming to be “wheat-free” doesn’t contain wheat; however, it potentially contains gluten, making it unsafe for individuals following a gluten-free diet to consume. Most foods containing wheat also contain gluten, but some wheat products are processed to remove gluten, such as wheat starch.
Is celiac disease the same asa wheat allergy?
Celiac disease is an autoimmune condition that causes damage to the small intestine when gluten is ingested, whereas a wheat allergy is an allergic response to wheat. Individuals with a wheat allergy may experience symptoms similar to celiac disease, but damage to the small intestine does not occur. Unlike celiac disease, many individuals outgrow a wheat allergy
by adulthood.
How do I know if I should follow a gluten-free diet?
If you are experiencing symptoms of celiac disease or gluten sensitivity, it’s best to consult your integrative healthcare provider for appropriate testing and recommendations before adopting a gluten-free diet. Celiac disease cannot be diagnosed based on symptoms alone. Your practitioner may perform a physical exam, order a serum antibody blood test that identifies tissue transglutaminase IgA antibodies, and recommend an intestinal biopsy to determine whether intestinal damage is present.
Gluten sensitivity can be more challenging
to diagnose. Your practitioner may order a blood test or food sensitivity test; however, these testing methods are not always accurate. In some cases, your practitioner may recommend that you follow an elimination diet to determine whether your symptoms are caused by gluten or another dietary offender.
How long should I follow the gluten-free diet?
Certain health conditions, such as celiac disease, require lifelong adoption of the gluten-free diet. For some individuals, however, following the gluten-free diet may be beneficial temporarily. Working with your integrative practitioner is the best way to understand how long you should follow the gluten-free diet.
Where’s the best place to find gluten-free foods?
Naturally gluten-free foods as well as specialty gluten-free foods can be found
in most grocery stores. Opting for naturally gluten-free foods is the most cost-effective way to enjoy a balanced gluten-free diet. Certain gluten-free grains can be purchased from local grocers, but some specialty or less common grains may need to be purchased from a health food market.
Can I eat at restaurants while following a gluten-free diet?
Yes! Many restaurants offer gluten-free menu items and are willing to accommodate your dietary restrictions. Dining out may require some additional planning ahead of time to ensure that the restaurant can safely prepare a meal for you.
A product says “may contain gluten” on its label. Can I safely eat it?
If you have celiac disease or you’re highly sensitive to gluten, you should avoid products that “may contain gluten” as the product might have come in contact with gluten during the manufacturing process.
Are foods labeled “gluten-free” the only products I can consume safely?
Not necessarily. “Gluten-free” is a voluntary label claim, meaning that even if a product doesn’t contain gluten, the manufacturer may or may not state that on the label. Choosing naturally gluten-free foods and reading
the ingredients list is the best practice for identifying unspecified gluten-free products. Individuals with concerns about gluten contamination should check with their integrative practitioner about selecting foods that are gluten-free.