When most people think of wheat-related health issues, they think of gluten, a protein found in wheat, barley, and rye that’s harmful for anyone with celiac disease. But gluten may not be the only culprit: A different family of proteins found in wheat and other grains—called amylase-trypsin inhibitors (ATIs)—has also piqued the interest of scientists in recent years. And now, German researchers say that ATIs appear to cause inflammation, and make chronic health conditions worse.
According to the scientists from the Johannes Gutenberg University, for some people, eating ATIs (which make up no more than 4% of wheat proteins) can trigger powerful immune responses in the gut that can affect other parts of the body, including the lymph nodes, kidneys, spleen, and brain.
This reaction can worsen chronic conditions, such as multiple sclerosis, asthma, rheumatoid arthritis, and inflammatory bowel diseases like Crohn’s disease and ulcerative colitis, they say. It also likely contributes to the development of a condition known as non-celiac gluten sensitivity, in which people test negative for celiac disease but still suffer gastrointestinal pain, fatigue, and other unpleasant symptoms after eating bread, pasta, and other wheat products. (Celiac disease is a serious condition in which an autoimmune reaction to gluten damages the intestines, causing diarrhea, weight loss, and nutritional deficiencies.)
Detlef Schuppan, MD, who holds faculty positions at both Johannes Gutenberg University and Harvard Medical School, presented these findings at UEG Week in Vienna, Austria, an annual meeting for gastroenterologists and digestive-disease researchers from around the world. His presentation was based on several studies published in the last few years, as well as some recent, yet-unpublished research.
"As well as contributing to the development of bowel-related inflammatory conditions, we believe that ATIs can promote inflammation of other immune-related chronic conditions outside of the bowel,” Dr. Schuppan said in a press release. He added that ATIs in wheat appear to “activate specific types of immune cells in the gut and other tissues, thereby potentially worsening the symptoms of pre-existing inflammatory illnesses."
Research has also shown that people with diagnosed non-celiac gluten sensitivities suffer a different type of inflammation than those with celiac disease, leading Dr. Schuppan and his Harvard colleagues to speculate that the symptoms—which can range from digestive issues to headaches, joint pain, and rashes—are actually caused by ATIs, not gluten.
A gluten-free diet tends to relieve these people’s symptoms, they say, because gluten and ATIs appear together in foods. "Rather than non-celiac gluten sensitivity, which implies that gluten solitarily causes the inflammation, a more precise name for the disease should be considered," Dr. Schuppan said.
Studies are currently in the works to examine the role that ATIs play in the progression of chronic health conditions. “We are hoping that this research can lead us towards being able to recommend an ATI-free diet to help treat a variety of potentially serious immunological disorders,” Dr. Schuppan said.
The effect of ATIs on inflammation appears to be dose-dependent. “A 90% reduction would likely be sufficient in most patients,” Dr. Schuppan wrote in an email to Health.
A Rutgers University study recently showed that the number of people following gluten-free diets has increased in the United States, even though diagnoses of celiac disease have remained stable. The authors hypothesized that people with so-called gluten sensitivities—either self-diagnosed or described by a doctor—could be partially responsible for the uptick. (Although others adopt a gluten-free diet due to the mistaken notion that it's healthier or an easy path to weight loss.)
But Dr. Schuppan thinks that many people who would benefit from avoiding wheat, and specifically ATIs, aren’t even aware that such a dietary change could help. “They usually have severe (e.g. autoimmune) diseases and are under strong medication anyhow,” he wrote.
More studies are needed before doctors can make specific recommendations or pinpoint groups of people who might be affected most. And the study needs to be published in a peer-reviewed medical journal so that it undergoes closer scrutiny. But Dr. Schuppan says that so far, his research has consistently led to one conclusion. “Bottom line," he wrote, "chronic diseases get worsened by ingestion of wheat (ATIs).”