Gluten is a protein found in wheat, barley, rye, and triticale, a combination of wheat and rye. It helps foods such as cereal, bread, and pasta, to hold their shape.
It is also found in some cosmetic products, such as lip balm, and in the glue on the back of stamps and envelopes.
In people with celiac disease, consuming just one crouton can cause health problems, as they cannot digest gluten at all. Following a diet that includes gluten can lead to severe illness. Going gluten-free can save the life of a person with celiac disease.
However, a survey by a market research company has found that almost 30 percent of adults in the U.S. are trying to reduce or eliminate gluten from their diet. Many of these do not have celiac disease.
For these people, is a gluten-free diet the best option?
Going gluten-free may not be for everybody.
A person with celiac disease must avoid all foods that contain gluten, even in the smallest amounts.
- any food made with cereals such as wheat, barley, triticale, rye, and malt
- some candies
- many desserts
- cakes and pies
- french fries
- processed meats
- sauce mixes
- brown-rice syrup
- malt derivatives, including malt loaf, malt vinegar, brewer's yeast, and malt-based beer and malted milk or milk shakes
- some types of soy sauce
- self-basting meat
Other items, and especially processed foods, can contain "hidden gluten." Anyone who needs to follow a gluten-free diet should check the food label to make sure there is no gluten in the product.
Oats can come into contact with wheat during production, so a person with celiac disease should avoid these unless they are labeled gluten-free.
Products sold as gluten-free may contain traces of gluten, especially if they were made in a factory that also produced regular wheat-based products.
Non-food items that may contain gluten include:
- lipstick, lip gloss, and lip balm
- play dough
- medications and supplements
- communion wafers
Many foods are naturally gluten-free.
- fruits and vegetables
- fresh eggs
- fresh meats
- fish and poultry
- unprocessed beans
- seeds and nuts
- most dairy products
- white rice
Grains and starches that may be allowed as part of a gluten-free diet include buckwheat, corn and cornmeal, flax, quinoa, rice, soy, arrowroot, and millet.
However, if these grains may have come into contact with grains, preservatives, or additives that contain gluten, a person with celiac disease should avoid them.
According to the Food and Drug Administration (FDA), food manufacturers can choose to use the label "gluten-free" on their products if the item meets the following conditions:
- It is inherently gluten-free, for example, fruits.
- It does not have ingredients that contain or are derived from a gluten-containing grain.
- It contains less than 20 parts per million (ppm) gluten, for example, in foods where the gluten has been removed
Many of our staple foods contain gluten, but a wide range of gluten-free alternatives, including breads and pastas, are now available in grocery stores.
Gluten-free produce is available for purchase online through Amazon.
However, there is little scientific evidence that a gluten-free diet is helpful for anyone without celiac disease or a gluten intolerance.
When is gluten bad?
Around 1 in 133 people in the U.S., have celiac disease, in which gluten triggers an autoimmune response that attacks the lining of the small intestine. The body cannot absorb nutrients into the bloodstream properly, leading to anemia, delayed growth, and weight loss, among other things.
In addition, there is a well-documented link between celiac disease and autoimmune disorders, such as thyroiditis.
For a person with celiac disease, the only effective treatment is a strict, lifelong gluten-free diet.
Results from the National Health and Nutrition Examination Survey (NHANES) 2009-2014 indicated that some 1.76 million people in the U.S. had celiac disease.
Meanwhile, the same report estimated that 2.7 million people were following a gluten-free diet without having celiac disease. Why?
Why go gluten-free without celiac disease?
According to the authors of the NHANES report, published in JAMA, the following may be reasons wht a growing number of people are following a gluten-free diet:
- public perception that a gluten-free diet is healthier and may improve nonspecific gastrointestinal symptoms
- gluten-free products are now more widely available
- a growing number of people are diagnosing themselves with a gluten sensitivity, rather than celiac disease, and they have noticed that their gastrointestinal health has improved after cutting out gluten
Those who follow a gluten-free diet without having celiac disease may be referred to as people without celiac disease avoiding gluten (PWAGs).
According to Beyond Celiac, formerly the National Celiac Awareness Foundation, some 18 million people in the U.S. report having some form of gluten intolerance, or non-celiac gluten sensitivity (NCGS). This can cause symptoms such as bloating or gas, diarrhea, fatigue, headache, "brain fog," and itchy skin rash.
A 2011 study, conducted in Australia, looked at the effect of a gluten-free diet on 34 people with irritable bowel syndrome (IBS). Participants followed either a gluten-free diet or placebo. The researchers concluded that NCGS "may exist," but the reasons why gluten might lead to gastrointestinal symptoms were unclear.
Benefits of a gluten-free diet
Research published in 2017 in the Expert Review of Gastroenterology and Hepatology suggested that gluten may cause intestinal symptoms, even in people without celiac disease.
- altered gut function
- irritable bowel syndrome (IBS)
- gut microbiome changes
A 2016 study that involved members of the same team revealed that some people with symptoms of NCGS experience systemic immune activation and damage to intestinal cells when consuming gluten.
What about autism, epilepsy, and schizophrenia?
Autism: Some studies have suggested a link between autism and gluten consumption, because people with autism have a higher chance of having IgG antigliadin antibodies, which can react to gluten. However, no causative link has been found, and the studies have been described as "flawed or too small to be statistically valid."
Epilepsy: There may be a link between celiac disease and epilepsy. In a study of 113 people with epilepsy, around 6 percent tested positive for celiac disease. A person who has this disease will benefit from avoiding gluten.
Schizophrenia: Small studies have suggested that people with schizophrenia appear to be more likely to have the antibodies involved in celiac disease. Avoiding gluten may help those who have the antibodies. Researchers say that "more research is critically needed" before recommending a gluten-free diet is recommended for a person with schizophrenia who has the antibodies.
This does not mean that avoiding gluten can cure schizophrenia, autism or epilepsy. It means that people with those conditions are more likely to have celiac disease.
Avoiding gluten does no harm
Rafe Bundy, a nutritionist and spokesperson for the Association for Nutrition, told MNT:
"There are many people around the world that consume a diet which is naturally gluten free or low in gluten. A good example is most of Asia, where the main staple food is rice, not wheat. It's perfectly possible to have a healthy diet which is also gluten-free diet using most standard dietary advice."
Some nutritionists believe that the focus on gluten-free diets and the growing availability of gluten-free foods may also be driving awareness of celiac disease. This is helpful for people with celiac disease.
A survey revealed that sales of gluten-free products in the U.S. rose by 16.4 percent in 2013-14, reaching $23.3 billion.
Following a gluten-free diet in the absence of celiac disease may be detrimental to health.
Whole grains, such as whole wheat bread, contain important nutrients. In addition, many products that contain gluten, such as rice and breakfast cereals, are also fortified with vitamins.
Fiber: Many gluten-free products are low in fiber. Avoiding whole grains can lead to a lack of fiber. This can be made up from lentils, beans, and so on, but the diet will need careful planning.
A study published in The BMJ in 2017 concluded that a person who follows a gluten-free diet without having celiac disease has a higher risk of cardiovascular disease in the long term. This is because they will miss out on the heart-healthy benefits of whole grains.
In addition, many processed gluten-free products can be higher in fat, sugar, and calories and lower in fiber than their gluten equivalents. This can lead to weight gain.
Gaynor Bussell, a dietitian and spokesperson for the United Kingdom's Association for Nutrition, told Medical News Today: "Gluten is only bad for health if you are a celiac."
Lisa Cimperman, a clinical dietitian at the University Hospitals Case Medical Center in Cleveland, OH, and a spokesperson for the Academy of Nutrition and Dietetics, told MNT:
"Gluten is neither essential nor detrimental to one's health or quality of diet."
Cimperman warns against assuming that "gluten-free" is healthful.
"The reality is that gluten-free junk food or desserts are certainly no healthier than their gluten-containing counterparts," she says.
Bussell believes that many people who follow the diet "have been duped by popular but poorly informed celebrities and media."
What does appear certain is that people who opt for a gluten-free diet need to plan carefully to avoid nutritional deficiencies.
Does gluten cause NCGS?
In 2013, the Australian research team who had suggeseted in 2011 that NCGS "may exist" overturned their previous findings. They concluded that there was no evidence of specific or dose-dependent effects in the participants thought to have NCGS.
The bloating they had previously identified, they said, might have been a reaction not to gluten but to types of carbohydrates called FODMAPs (fermentable, oligo-, di-, monosaccharides, and polyols).
These FODMAPs are present in gluten-containing grains. This could explain why people with IBS show improvement in symptoms when on a gluten-free diet.
In 2014, a study published in the Journal of Proteome Research suggested that non-gluten wheat proteins—serpins, purinins, alpha-amylase/protease inhibitors, globulins, and farinins—may be triggers involved in celiac disease.
Clearly, the value of a gluten-free diet for people without celiac disease needs more investigation.
Anyone who is thinking of eliminating gluten from their diet should take some steps to prepare.
- discussing any gastrointestinal symptoms, such as chronic or severe abdominal pain, bloating, or diarrhea, with a doctor, who may need to assess for other conditions
- continuing to consume gluten until you have been tested for celiac disease, as cutting out gluten may lead to a false negative test result
- talking to a dietitian before cutting out gluten, to make sure the diet will include all the essential nutrients
The question appears to be: Is a gluten-free diet for everyone, or only for people with celiac disease?