In my effort to broaden the focus of this blog, I want to discuss a food fad that lacks scientific support — gluten-free diets. If you listen to the quacks on the internet, apparently organic, GMO-free, gluten-free diets will fix all that ails you and your kids.
Except it won’t unless you suffer from very rare medical conditions that make you very sensitive to gluten.
Like a lot of food fads, such as avoiding fats or carbohydrates, gluten-free diets seem to have a basis in real science and medicine, but it has exploded far beyond what real science-based medicine would recommend, and that would be to a very tiny patient population.
Let’s take a look at gluten and this diet fad.
What is gluten?
Gluten is a protein found in wheat and is similar to proteins found in common grains such as barley and rye. Generally, we like gluten, because it gives elasticity to dough, allowing bread to have that chewy texture that is an important component of the pleasure of eating.
Without trying to be a Food Network Star, gluten is critical in baking everything from bagels to cakes. Generally, kneading the dough forms long chain gluten protein molecules giving a chewier and chewier texture. Pasta, bread, and so many other foods are made with high gluten flour that is worked hard to create longer chain proteins. Yes, good cooking involves intense knowledge of chemistry.
Gluten can be removed from the milled flour (or it can be added back). Purified gluten, because of its texture, is used to create fake meat products, so beloved (or not) by vegans.
So what is real gluten sensitivity?
Yes, some people are sensitive to gluten. Celiac disease (also known as coeliac disease in British English) is a genetic autoimmune disorder that afflicts the small intestine of individuals. This disease afflicts between 1 in 1,750 and 1 in 105 people in the United States (or about 0.05 to 1%), a tiny number.
When a person with celiac disease eats gluten, it causes severe damage to the small intestine and the body cannot absorb nutrients. They may also experience symptoms such as diarrhea, vomiting, skin rashes, joint pain, headaches, and overall mental fogginess.
Although the disease is not completely understood, in a person with celiac disease who is exposed to gluten, the immune system causes an inflammatory reaction to the lining of the small intestine. This interferes with the absorption of nutrients. The only known effective treatment is a lifelong gluten-free diet.
This disease should not be confused with a wheat allergy, which is also caused by a reaction to wheat proteins, which can include gluten. However, there are over 20 different wheat proteins that have been identified as causing wheat allergies, and gluten generally is not the cause of wheat allergy. Finally, wheat allergies are extremely rare, and the gluten form of wheat allergies is so rare that it would take a huge population to detect them.
Outside of celiac disease and wheat allergies, both of which can be diagnosed objectively through comprehensive medical tests, there is a large group (by some reports, over 100 million Americans) who claim that they have some mysterious gluten sensitivity, which has a real name, non-celiac gluten sensitivity.
There is some research into this potentially real or mythical condition, called nonceliac gluten sensitivity, and there might be a small (smaller than the numbers for celiac disease or wheat allergy) number of people with a previously unknown type of gluten sensitivity, but the evidence isn’t there. However, many researchers reject the existence of this condition, and some have stated that it may not be gluten, but fructan, which is a long polymer of fructose molecules.
Let’s be scientific here — humans have evolved with cereal grains for 20-30 thousand years, so in modern human evolution, those who couldn’t consume wheat would have been selected against by natural selection.
That there are 100 million Americans who have this deleterious mutation that caused some unknown gluten sensitivity boggles the mind — it’s just not plausible. Right now, the vast body of evidence does not support this mysterious gluten sensitivity, no matter how hard you want to believe it.
For those with a real diagnosed wheat gluten allergy or celiac disease, treatment is simple – 100% gluten-free diets. I’m guessing that this new food fad has made gluten-free diets much more accessible to people with real gluten issues because, from a business point of view, most food manufacturers wouldn’t make gluten-free foods for the less than 1% of the population who have a true gluten sensitivity.
But, there are multiple problems with a gluten-free diet:
- Strict adherence to a gluten-free diet may limit the amount of folate, fiber, iron, and other micronutrients consumed.
- Compliance may be an issue since products may not be labeled correctly, or individuals choose to eat grain-containing foods just for variety. Inadvertent gluten exposure is common. Biopsy of the small intestine 2 years after adopting a gluten-free diet shows tissue damage persisting in up to 50% of adults and 25% of children with celiac disease.
- According to one study, regular consumption of as little as 50 mg gluten, the amount found in 1/100th of a standard slice of wheat bread, damages the intestine in celiac disease. A typical Western diet contains 16 g of gluten, more than 300-times the minimal toxic dose for someone with celiac disease.
- This study concludes that persistent inflammation of the small intestine is associated with a greater risk of cancer and osteoporosis.
- One of the most important considerations is that a gluten-free diet costs about $2,000 annually, more than many medications.
- A gluten-free diet may increase the risk of type 2 diabetes.
So if you really have a real gluten sensitivity, it isn’t a matter of telling people that you have a gluten sensitivity, watching your diet is a matter of life or death. For those with real celiac disease or wheat gluten allergies, even a tiny amount of gluten is dangerous. And it’s not the “I don’t have the energy” kind of dangerous, it could be life-threatening kind of dangerous.
The signs of an imaginary gluten sensitivity
Here are some of the signs of those who are probably not gluten-sensitive.
- A real physician hasn’t diagnosed gluten sensitivity using real diagnostic tools. Once a person is diagnosed, usually during childhood, then it’s not something that becomes party conversations. One doesn’t bring up the fact that one crouton in a salad may make your intestinal tract fall out of your body into the toilet. Because that’s a real gluten sensitivity.
- Still chugging beers. Beer is bottled gluten water. If you drink beer, you do not have a real gluten sensitivity.
- Trying to “watch your gluten consumption.” Sorry, but celiac disease and real wheat gluten allergies are on/off diseases. That is, there is no acceptable amount to consume, any amount is dangerous. There are individuals who can lick a piece of bread, not eat it, and fall over sick. Again, you can’t “watch” the amount of gluten you eat, you watch for every tiny bit of gluten that may appear anywhere. Someone with real gluten sensitivities is obsessive about their food because not doing it is dangerous. Bragging to someone that you’re “watching” your gluten probably means you don’t have a real gluten sensitivity.
- Your gluten knowledge comes from Natural News, The Food Babe, or another pseudoscience website. Your knowledge of gluten should come from your physician, preferably a gastroenterologist, and with additional information from a science-based national or international celiac disease organization. It’s easy to diagnose celiac disease or a wheat gluten allergy. If you have some other type of gluten sensitivity, it’s important that your physician establishes that it is real or not related to a more serious chronic disease.
- You claim you feel better without gluten. Someone with real gluten sensitivity didn’t develop it when they turned 30. It’s something that mostly (but not always) shows up in childhood, and a real celiac disease child won’t say they feel better without gluten, they’ll say how horrible it is when they accidentally consume it. It’s not some new age therapy with intangible results like “I can’t point it out, but I just feel like a new person.” Real gluten sensitivity means if you have gluten, you want to rip your intestines out of your body without anesthesia.
- You say that it’s easy to eliminate gluten. No, it isn’t. And it’s not eliminating 99% of gluten, it’s eliminating 100% of any gluten anywhere. It’s very difficult to do. It takes time to do shopping (parents of celiac children are obsessive about food labels). It means supplementing your diet with other proteins and with micronutrients that are missing when you remove gluten. It’s asking a waiter or caterer whether any gluten products even touch the food or are used in some sauce. It’s being preoccupied with every aspect of your diet while worrying if the next food item is going to cause massive pain and discomfort. This isn’t easy, it sounds pretty close to impossible, and that’s why if you say it is easy, you probably do not have any type of gluten sensitivity.
Gluten-free diets may cause harm
A paper, by Dr. Charlene Elliott of the University of Calgary, published in August 2018 in Pediatrics examined foods marketed for children that were labeled “gluten-free.” She compared the actual nutritional content of these foods to similar foods that were not labeled as such.
Junk foods, such as confectionary products (candy), potato chips, cheese-flavored snacks (like Cheetos), sugary sodas, and similar products, were excluded from this analysis. Dr. Elliott focused on products that specifically targeted children by meeting one of the following criteria:
- the product or brand name contains the word “kids” or “child;”
- links with children’s television programs, merchandise, or movies;
- promoted for lunchboxes such as the Lunchables product;
- utilizes graphics or activities that are child-friendly;
- contains the word “fun,” “play,” or “kid(s)” on the package;
- contains premium offers for children, such as a free gift or download; and
- uses child-oriented shapes, unusual colors, or playful product names or tastes.
I think that we all know what foods are targeted to children, but since this study was published in a high-ranked peer-reviewed journal, Pediatrics, Dr. Elliott was careful to lay out exactly what would be considered a gluten-free food targeted to children.
Dr. Elliott standardized nutritional content to 100g servings to make comparisons valid. She analyzed 374 food products that were targeted at children, 66 of which were labeled as gluten-free.
Despite the belief that gluten-free foods targeted at children are somehow nutritionally superior to those without that claim, it was clear that the foods were fairly similar. In fact, the results show that the overall nutritional content of gluten-free foods is equivalent to foods that weren’t labeled as such.
However, there were some interesting findings in this study. Although it was not statistically significant, the research found that gluten-free foods contained less protein. Since gluten is a protein, the lack of it could account for some of that difference. Protein contents of foods are often overlooked when examining food labels.
When these foods were compared utilizing the Pan American Health Organization Nutrient Profile Model (pdf), a guideline for packaged foods and diets for children, 88% of the packaged gluten-free foods targeted to children were classified as “unhealthy.” Of course, this compares to 97% of non-labeled foods. These pre-packaged foods for children are just not that great for nutrition, whether filled with gluten or not.
The results of this study have some far-reaching implications. Both children with or without gluten sensitivity may not be getting adequate nutrition from these gluten-free packaged foods.
Despite the claims that “gluten-free” foods are somehow healthier for children, these foods contained high levels of sugar, sodium, and/or fat. There appears to be no nutritional advantage for these foods compared to gluten-filled foods.
Dr. Elliott concluded that:
As the first study in which the nutritional quality of GF supermarket products targeted at children are examined, this research reveals that products with a GF claim are not nutritionally superior. This has implications for parents who seek healthy products for their children, especially in the case of children with CD (for whom gluten must be avoided), but also in the case of parents who mistakenly believe that GF products will confer health benefits. It is important to unsettle the assumption that GF food equals healthy, which has functioned as an excellent sales tool for the food industry but does little to support public health. Reminding parents and caregivers to read the nutrition facts table and to serve whole, unprocessed foods is 1 step in the right direction; so too is the development of a policy that allows consumers to easily assess the nutritional quality of packaged products (such as an easily understood, federally regulated front-of-pack symbol). This is particularly important in light of the finding that foods targeted at children in general (both GF and regular products) are of poor nutritional quality.
Low gluten diet and type 2 diabetes
Just for background, type 2 diabetes mellitus (or type 2 diabetes, T2DM) is a metabolic disorder that is characterized by high blood glucose with insulin resistance and relative insulin deficiency. In general, someone with T2DM produces low (or maybe even adequate) levels of insulin, but various cells and organs become resistant to insulin, so cells don’t remove or store blood glucose.
Although the cause of T2DM is not completely understood, it results from a complex interaction between diet, obesity, genetics, age, and gender. Some of the causes of T2DM are under a person’s own control, like diet and obesity, but many of the factors aren’t.
Because they are often confused, it’s important to note that T2DM has a completely different cause and pathophysiology than type 1 diabetes mellitus (T1DM, once called juvenile diabetes). Type 1 diabetes results from the inability of the beta cells of the pancreas to produce insulin, as a result of an autoimmune disease.
In an article published on 3 August 2018 in Diabetologia, the research found that lower consumption of gluten may be linked to a higher risk of type 2 diabetes. In this long-term observational study, researchers found that most participants had gluten intake below 12 grams/day, and within this range, those who ate the most gluten had lower Type 2 diabetes risk during thirty years of follow-up. Study participants who ate less gluten also tended to eat less cereal fiber, a known protective factor for Type 2 diabetes development.
After further accounting for the potential effect of cereal fiber, individuals with the highest 20 percent of gluten consumption had a 13 percent lower risk of developing Type 2 diabetes in comparison to those with the lowest daily gluten consumption (approximately fewer than 4 grams).
The researchers had estimated the daily intake for nearly 200,000 participants in three different long-term health studies. The study included 4.24 million person-years of follow-up from 1984-1990 to 2010-2013, during which 15,947 cases of type 2 diabetes were diagnosed and confirmed.
Although this study seems, on the surface, impressive, there are several important issues to address:
- This is an observational study where the study participants reported their gluten consumption in diaries. I’ve never been a fan of this type of study because they are prone to errors in memory.
- The study population included only nurses and other health care professionals. It’s a subsection of individuals that may be more careful with their health choices than the general public.
- The study lacks a control group that did not consume any gluten – this study was set up well before gluten became a food fad.
Obviously, the study’s limitations indicate that we might want to wait until follow-up studies confirm or refute this potential link. The authors did conclude that:
Gluten intake is inversely associated with type 2 diabetes risk among largely healthy US men and women. Limiting gluten in the diet is associated with lower intake of cereal fibre and possibly other beneficial nutrients that contribute to good health.
Summary, the tl;dr version
So, if you run into anyone who exhibits any of those six signs I wrote above, you probably can place them into the category of mostly imaginary gluten sensitivity.
It’s important to note that real gluten sensitivity is a known, real disease, and its treatment is difficult. But it is very rare, and as I said, it can be easily diagnosed. Sufferers of the disease know that there’s a difference between a tiny bit of gluten in the diet and none at all–it’s painful and terrible.
Again, the benefit of this food fad is that individuals with real gluten sensitivity now have better accessibility to gluten-free foods. And that’s good. Sadly, this fad too shall pass, and then those who need it will have to search again for gluten-free foods.
One last point — gluten-free diets are not “healthier,” unless you have a real gluten sensitivity. A lot of people think eating a gluten-free muffin or cookie is somehow a healthier choice than eating one with gluten in it. Those gluten-free products are no different than their gluten-containing counterparts — they’re still full of sugar and less healthy fats.
And there are studies that show that gluten-free foods are not necessarily healthier and may contribute to type 2 diabetes. You have been warned.
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