Gluten may not be the only protein in wheat causing people tummy upset and headaches.
Scientists in Germany say another family of proteins found in wheat, called amylase-trypsin inhibitors (ATIs), can trigger chronic health conditions such as multiple sclerosis and asthma.
According to the research presented at United European Gastroenterology Week 2016, ATIs also contribute to non-coeliac sensitivity - in which people test negative for coeliac disease but still suffer gastrointestinal pain, fatigue and other unpleasant symptoms after eating wheat products.
ATIs make up no more than four per cent of wheat proteins but can trigger powerful immune reactions in the gut that can spread to other tissues in the body, says lead researcher Professor Detlef Schuppan from the Johannes Gutenberg University in Germany.
He says it's possible ATIs may worsen the symptoms of rheumatoid arthritis, multiple sclerosis, asthma, lupus and non-alcoholic fatty liver disease, as well as inflammatory bowel disease.
"The type of gut inflammation seen in non-coeliac gluten sensitivity differs from that caused by coeliac disease, and we do not believe that this is triggered by gluten proteins."
"Instead, we demonstrated that ATIs from wheat, that are also contaminating commercial gluten, activate specific types of immune cells in the gut and other tissues, thereby potentially worsening the symptoms of pre-existing inflammatory illnesses," Prof Schuppan said.
Coeliac disease is a chronic autoimmune condition triggered by the consumption of gluten.
It's believed ATIs could also explain the extra-intestinal symptoms, such as migraine headaches, many people experience after consuming wheat-based products.
It's acknowledged there's currently no clinical evidence to support the assumptions made by the German researchers and clinical studies are due to commence to explore the role that ATIs play on chronic health conditions in more detail.
"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," said Prof Schuppan.
