Celiac disease is on the rise. Why?

A few decades ago, the initialization “GF” on a menu could easily be mistaken for “good food”. Nowadays, it’s widely known to stand for “gluten-free,” and now the shorthand is adorning restaurant menu items nationwide. This shift in understanding is partly due to the rise in celiac disease, an immune reaction to gluten that causes inflammation and atrophy in the gut. Coupled with increased awareness and access to the internet, the gluten-free life is no longer just for the health-conscious; rather, celiac disease is an extremely common condition whose numbers continue to rise every year.

According to Dr. Peter Green, director of Columbia University’s Celiac Disease Center, celiac disease has increased fivefold in the past 50 years, with most occurring in the 1990s. A meta-analysis study published in the American Journal of Gastroenterology in 2020 supports this claim, finding that celiac disease is on the rise throughout the Western world, with higher incidence rates in women and children.

The reason for this rise in celiac disease continues to vex scientists. Yet there are some compelling theories as to what could be causing it.

“We don’t know why it’s increased,” Green said. “But there is evidence that it is stabilizing,” she said, pointing to some research from Finland.

Despite a common misconception, celiac disease is not a gastrointestinal disease, but an autoimmune one. People with celiac disease have developed an immune reaction to gluten, which is a protein found in wheat, rye, barley and triticale.

Green said it’s not a “typical” allergy, so to speak, because the response can be delayed.

“There’s a period of time where an individual tolerates gluten and then, for some reason, they develop this immune reaction that causes inflammation, antibody development, inflammation in the gut that causes atrophy,” Green said.

In particular, doctors say that many people with celiac disease are misdiagnosed. One problem is that doctors often don’t think about the diagnosis, in part because symptoms can vary. Effects include bloating, chronic diarrhea, constipation, gas, lactose intolerance, nausea, vomiting, or pain in the abdomen. A flare-up can physically manifest itself as an itchy rash on a person’s skin that can look like clusters of bumps or blisters.

Green said that “doctors’ inability” to think about diagnosis, and lack of knowledge about tests and how a diagnosis should be made, is the main cause of people not being diagnosed.

“We often hear stories, people say, ‘I’ve been going to a doctor for a long time and then the doctor brought a new person into the office and a new person diagnosed me’ or ‘I saw doctors and then I had to go to the ER for some reason and the ER doctor diagnosed me with celiac disease,'” Green said. “Often we see people being told they have celiac disease based on very false information.”

However, with so many unknowns surrounding celiac disease like how many people have it and what is causing the increase, misinformation follows. A search on Instagram with the hashtag #glutenfree yields over 41 million posts. Between holistic healers peddling untested remedies and pseudoscience about the effects of gluten, it can be tough sifting through the noise. Yet some in the medical and scientific community have actively researched possible reasons for this dramatic increase in autoimmune problems with ingesting wheat.

One often seen and unsubstantiated rumor about the cause of celiac disease has to do with the industrial handling of grains.

“One of the common myths out there is ‘we have genetically modified wheat,'” Dr. Amy Burkhart, a physician and registered dietitian, told Salon. ‘But there is no genetically modified wheat in the United States’

Yet some patients insist there is something different about American wheat. Both doctors said they have heard of patients with gluten sensitivity who have reported visiting another country, for example in Europe, where food safety standards are stricter, where they ate food with gluten without having symptoms.

“I’ve heard this, and it’s a really interesting kind of phenomenon, but it’s important to say that these are people with gluten sensitivity, not celiac disease. People with celiac disease should never go to Europe assuming they can eat gluten-containing foods” Burkhart said.

She noted that those with a gluten sensitivity have a spectrum of gluten they can tolerate.

“People think that maybe because the gluten content of wheat in Europe is lower maybe it’s because the growing conditions are different and the climate where the wheat is grown can influence the amount of gluten in that food.”

Burkhart said there are more additives in food in America than in Europe, which may be part of the phenomenon. Green said he suspects high fructose corn syrup may be part of the reason people with gluten sensitivities feel better eating abroad.

“I have a lot of patients who go to Europe and say ‘my stomach feels good,’ but we don’t know what’s causing it,” Green said. “Food is different in the US, but part of that is always the high fructose corn syrup that people add to food in the US, as a substitute for sugar.”

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But Green pointed out that wheat in America is almost certainly not the cause of the rise in celiac disease. You pointed out that celiac disease is also on the rise in countries like Australia and Canada. She said theories suggesting that wheat has been altered or that gluten has changed in the last hundred years aren’t true either.

“There’s actually less gluten ingested by the public now than there was 100 years ago,” Green said. “Celiac disease has increased, and we don’t know why, but autoimmune diseases and allergies have also increased and we don’t know why.”

Burkhart said he believes that an increase in public awareness of celiac disease has understandably played a role in the rise of celiac disease, as well as an increase in testing and the rise of the internet as a forum for medical discussion.

“People talk, information is shared, and symptoms are discussed; this quickly spreads awareness of information, including information about celiac disease,” Burkhart said. “Patients have started asking for the test and recommending it to friends; some of these patients have obviously been diagnosed with celiac disease and might not have thought otherwise about celiac disease or asked for the test if they hadn’t read about someone with similar symptoms.”

Despite the mystery surrounding celiac disease, Green said researchers struggle with a lack of funds that could help them get answers.

Celiac disease “hasn’t received a great deal of research money,” Green said. “It’s been understudied… there are actually only a few individuals, worldwide, who have demonstrated the mechanism of celiac disease.”

So, some researchers are doing a lot of leg work, Green said. “We know how the gluten fragment interacts with the immune system and causes inflammation in the gut…it was developed by a few people.”