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Once upon a time, no one had any idea what gluten was. Now, it feels as though gluten-free restaurants/food aisles/lifestyles are popping up everywhere you look. Interest in gluten-free diets has been spurred by renewed research in the medical community and popularization of such diets by the press. But what does going gluten-free really mean, and how do you know if it’s something you should pursue? Here’s the quick guide to gluten and its related conditions. Read on before you transform your diet!

What is gluten?

Gluten is a protein found in cereal grains including wheat, rye, and barley. Gluten is not inherently harmful.  Certain people, however, possess genes or other factors that it difficult for them to digest gluten; it can even damage their gut. These individuals may have one of the gluten-related disorders described below and would benefit from a gluten-free diet.

Celiac disease, gluten intolerance (sensitivity) and wheat allergy – what’s the difference?

1. Celiac disease. For those with celiac disease, gluten causes an autoimmune reaction in the gut (meaning that the cells that normally protect the gut start attacking it). They damage the lining of the gut, leading to poor absorption of nutrients.

Symptoms of celiac disease are variable, but they may include the following: diarrhea, abdominal pain, nausea, vomiting, bloating/gas, constipation, fatigue, joint pain, weight loss, headache, mouth ulcers, and skin rashes. Individuals with celiac disease may be at risk of vitamin and nutrient deficiencies (i.e. iron, vitamin B12,or  folate), osteopenia (brittle bones), fertility problems, and small bowel cancers.

The first steps to diagnosing celiac disease are screening blood tests, followed by an upper endoscopy (a camera test to biopsy the gut) to confirm the diagnosis. At this point in time, a diagnosis of celiac disease requires strict adherence to a life-long gluten-free diet; with that in mind, the diagnosis is not given lightly.  Furthermore, there is a strong genetic link of celiac disease in families. If someone is diagnosed with celiac disease, it is recommended that all first-degree relatives (parents, brothers, sisters, children) undergo screening laboratory tests, even if they’re asymptomatic. Thus, an individual’s diagnosis of celiac disease can have health implications for their entire family.

2. Gluten intolerance (sensitivity). People with gluten intolerance may have many of the same symptoms as those with celiac disease, but the main distinction is that their condition doesn’t result in autoimmune destruction of the gut.  As such, they aren’t at risk of the same nutritional complications as someone with celiac disease. Individuals with gluten intolerance will have normal screening tests for celiac disease and a normal appearing gut if they were to undergo an upper endoscopy. If they avoid gluten, their symptoms and sense of well-being improve, but they do not require the same intensive monitoring for nutritional deficiencies and complications that a person with celiac disease needs over the long-term. Their family members don’t need any specific testing.

3. Wheat allergy. Wheat allergy is caused by a different part of the immune system than celiac disease. The symptoms of wheat allergy can mimic those of celiac disease and gluten intolerance; they can also consist of  classic allergy symptoms, such as hives and difficulty breathing. Wheat allergy can be diagnosed by skin testing performed by an allergist. It is important for people to know if they have a true food allergy, as those with severe reactions may need to carry an epinephrine pen (a kind of rescue medication for allergic reactions) to halt a reaction.

Why does all of this matter for your health? As outlined above, each of the different gluten-related disorders has specific implications for health. Some require drastic changes for a lifetime; some require some smaller adjustments. And, from a healthcare cost perspective, these diagnoses may impact aspects of insurance such as premiums or notation of pre-existing conditions.  

Considerations before starting a gluten-free diet

1.  Visit with a healthcare provider to determine which, if any, of the gluten related conditions you may have above. Don’t decide ahead of time and make adjustments. Once someone has been on a gluten-free diet for a period of time, screening laboratory tests for celiac disease may not be as accurate. If you want to know whether you have celiac disease, it is best to continue eating gluten as usual until your testing is completed.

2. Consult with a dietician well-versed in a gluten-free diet. Embarking on a gluten-free diet goes beyond simply strolling down the gluten-free aisles at your local grocery store. Food products such as soy, teriyaki and hoisin sauces, imitation crabmeat, regular oatmeal or granola, and malt extracts in cereals contain gluten and can easily be overlooked. The food allergen labeling law of 2006 requires “wheat” to clearly be listed on food labels in an allergen; however, rye and barley (and malt derivatives) are not included thus these need to be clearly checked for on the label. Guidance from a dietician experienced in the gluten-free diet will aid in making healthy and safe food choices. 

3. Educate yourself about non-obvious sources of gluten. Gluten is not just in food, but may also be found in toothpaste, lip balms, and medication fillers. These products also do not fall under the same labeling laws as food thus “wheat” does not need to be clearly identified on the label as well as other gluten containing ingredients. Individuals with celiac disease and extreme forms of gluten intolerance need to be aware of gluten in non-food products that may be ingested.

4. Budget your grocery list.  Gluten-free foods are more expensive than regular products by approximately $1.00 per unit of food. Expect to spend more money on fewer food products, and budget your grocery list accordingly. You will save the most money by choosing foods that are naturally gluten-free, like fruits, vegetables, lean proteins, plain nuts/seeds, complex carbohydrates like sweet potatoes, corn, and peas, and naturally gluten-free grains like rice, quinoa, and polenta.

5. Consider effects on family meal planning and dining out.  For families or individuals sharing kitchens, it needs to be established if everyone or just some of the people in the residence will be going gluten-free.  People with celiac disease and extreme gluten intolerance can be affected by cross-contamination of gluten-containing products on kitchen surfaces. With that in mind, if gluten is going to remain in some of the foods in the home, cleaning practices and avoidance of cross contamination are paramount. Finally while a growing number of restaurants provide gluten-free food options, the availability remains more limited than regular foods. Note that a gluten free menu in a restaurant does not always mean that your food will be prepared separately from gluten containing foods. It is good to inquire about staff training and prevention of cross-contamination procedures. Understanding one’s medical need for a gluten-free diet can help you figure out how strict to be with food choices when dining out.


Special Thanks to Leslie Gaillard, MPH RD LDN for editing the nutritional information within this article. Leslie is a registered and licensed dietitian. Leslie offers local and remote nutrition counseling and consulting services. To work with Leslie, contact her at

Dr. Nancy McGreal is an Assistant Professor of Medicine and Pediatrics in the divisions of adult and pediatric Gastroenterology at Duke University. Dr. McGreal graduated from the University of North Carolina-Chapel Hill with a BS in Biology and Psychology. She attended medical school at the University of Maryland and completed a residency in Combined Internal Medicine-Pediatrics at the University of California-San Diego. During her training, Dr. McGreal developed an interest in inflammatory bowel disease (IBD) and continuity of care in the treatment of chronic illness over the lifespan. She subsequently completed fellowship training in adult and pediatric gastroenterology at the University of Chicago. Dr. McGreal utilizes her unique combined training to care for children and adolescents afflicted with chronic gastrointestinal disorders aiding their transition to adulthood. read more about