Gluten has been all over the news recently with the rise of gluten free fad diets but is everyone really allergic to gluten? Celiac disease is a condition in which the microvilli of the small intestine become damaged by gluten, or more specifically an immune reaction to the protein gliadin that causes the damage. Celiac disease is characterized by: weight loss (due to an inability to absorb critical nutrients), fatigue, cramps, bloating, irritability, chronic diarrhea, and anemia. The only known treatment for celiac disease is a diet free of gluten and therefore the recent advancements in the availability of gluten free foods that are tasty is both helpful and meaningful to these people. The main reason for all these new gluten free foods is the explosion of so called gluten intolerance or sensitivity. People with non-celiac gluten sensitivity (NCGS) describe symptoms like a foggy mind, constipation, bone or joint pain, and ADHD like behaviours. While true celiac disease has a prevalence of around 1 in every 141 people in the US, NCGS has a prevalence of around 1 in 17 people and appears to be on the rise. So what is this mysterious new illness causing us all to shun gluten? Research out of Australia suggests we could be blaming the wrong thing.
The research, published in Gastroenterology, found that in a double blind trial when patients were all placed on similar diets, gluten did not induce NCGS like symptoms in patients with diagnosed NCGS. Whether the people were fed food high in gluten, low in gluten or a placebo diet (no gluten, high protein), they all had similar changes in symptom scores. These symptoms included pain, bloating and tiredness. The researchers also measured the levels of various markers of gluten intolerance including gliadin levels, eosinophil markers, and fecal characteristics, all of which where not different between the different diets. So does this mean that gluten sensitivity is not real? Sort of, the symptoms these people experience are real but it does not seem to be gluten that is causing the problem. The researchers made sure every person had a diet low in what are called FODMAPs. The researchers last paper, which showed changes in NCGS symptom scores with gluten diets, did not have FODMAPs controlled for in the diets. FODMAPs are short carbohydrates that are poorly absorbed in the small intestine. They include fructose, galactose, lactose and sorbitol. It is suggested by the authors that it is these FODMAPs that are responsible for the symptoms that patients with NCGS are feeling and not gluten. The reason gluten free diets seem to help ease the symptoms are because most foods with FODMAPs also contain gluten. FODMAP high foods include: garlic, onions, apples, pears, wheat containing breads, agave, sugar free sweets and beer. Most of these foods do not contain gluten and could cause similar symptoms associated with gluten in NCGS people. People with irritable bowel syndrome often find help from low FODMAP diets and therefore people with NCGS might find relief in one of these diets.
So while the rise in “gluten” intolerance has helped increase the awareness of the need for better gluten free meal options, NCGS is not likely due to gluten and therefore has been falsely accused of causing many problems. Gluten free diets might help people feel better primarily because it forces them to eat healthier. Lots of our favorite foods contain gluten (cake, crackers, cookies, bread, etc) while most of the food that is used for gluten free diets is healthier (fruits, veggies, whole grains). Future research should focus on the role of FODMAPs in not only NCGS symptoms but also in the aggravation of celiac disease. Perhaps gluten injury to the small intestine is amplified by FODMAPs, we don’t know. Other research should also look into the effectiveness of FODMAP reduced diets in limiting symptoms experienced by NCGS patients.
So whether you find relief from gluten free diets because they help you avoid FODMAPs or because they force you to eat healthier, the cause of your discomfort is not likely gluten (unless you are celiac). NCGS should therefore be called NCFODMAPS? Not so easy to get out, we will have to come up with a better acronym.