Pamela A. Popper, Ph.D., N.D.

Wellness Forum Health

 Discussion about gluten and grains has become confusing to consumers because of the misinformation they read regularly in consumer publications and diet books, and due to some very popular but not very science-based best-selling books. Without much if any evidence, some healthcare practitioners advise everyone to stay away from grains, claiming that grains and gluten are the cause of most health issues. They are wrong about this, and the research is quite clear on this issue.

On the other side of the issue are some physicians who say that there is no reason for anyone who does not have celiac disease to avoid gluten-containing foods. These doctors are just as wrong as the anti-grain/anti-gluten folks. As with many things, the answer is in the middle.

What is gluten?

Gluten is a protein concentrated in grains like barley, rye, and wheat, but also found in smaller quantities in grains like triticale, spelt, and kamut. Oats are theoretically gluten-free, but it is estimated that 88% of the oats sold in Canada are contaminated with gluten[1] and in one sampling of of U.S. oats, all tested positive for gluten contamination.[2]

Who should eliminate gluten from the diet?

People who have celiac disease should eat a medically gluten-free diet, meaning that they can consume absolutely no gluten-containing foods or food products containing even trace amounts of gluten. For people with celiac disease, even a tiny amount of gluten causes atrophy of the villi in the duodenum and intestinal permeability, which eventually leads to unpleasant symptoms, nutritional deficiencies, and increased risk of several diseases.

But it has become apparent that there are others who may not have celiac disease but who do have symptoms related to gluten consumption that get better or resolve when high-gluten foods are eliminated. These can include gastrointestinal symptoms such as gas, bloating, cramping, and diarrhea; skin rashes, headaches, and other issues.

In one study, researchers looked at two groups of patients, some with symptoms of Irritable Bowel Syndrome and another group without symptoms to determine whether the incidence of celiac disease was higher in those with symptoms of IBS. There were no differences in incidence between the groups. But the researchers did find antibodies for tissue transglutiminase, gliadin and endomysium in the patients with IBS. They did not have celiac disease, by they were reacting to gluten-containing foods.[3]

Another study included patients who had IBS trending to diarrhea and found that they did not show evidence of celiac disease after duodenal biopsies, but they did test positive for genetic markers for celiac like HLA-DQ2 or DQ8.  Additionally, those patients with antibodies to transglutiminase, gliadin and endomysium showed improvement in symptoms after gluten elimination.[4]

The term for gluten-induced symptoms in patients without celiac disease is non-celiac gluten sensitivity (NCGS), and blind oral challenges show that it is a real condition.

In one study, researchers conducted a randomized, double-blind, placebo-controlled, cross-over trial to determine the effects of gluten intake on patients suspected of having NCGS. 61 patients without celiac disease or wheat allergy who identified themselves as being sensitive to gluten in participants were randomly assigned to consume 4.375 g/day of gluten or rice starch (placebo) for one week in capsules. After eating a gluten-free diet for one week, the participants were crossed over to the other group.

59 patients completed the trial, and for those, gluten significantly increased symptoms as compared to placebo. The subjects reported that abdominal bloating and pain, foggy mind, oral canker sores, and depression were significantly more severe when they consumed gluten vs placebo. The amount of gluten that triggered symptoms in this study is slightly more than the amount in a typical slice of bread.[5]

Gluten has also been identified as a trigger food in the development of some autoimmune conditions and restricting it has been shown to be helpful to patients with diseases such as rheumatoid arthritis.[6]

What Does This Mean for the General Population?

Celiac patients should avoid all gluten; and those who have certain conditions like autoimmune diseases or who react to gluten should avoid high-gluten foods (barley, rye and wheat; gluten-free oats are allowed). The rest of the population can eat gluten-containing foods if they choose to; there is no need for restriction.

It is important not to apply dietary restrictions that pertain to a small percentage of the population to the entire population. For example, there are people who cannot eat tree nuts; they go into anaphylactic shock when they do. But this does not mean that the rest of the population cannot eat tree nuts.  The same is true with gluten. It’s fine for most people; those with real reactions or issues should avoid it.

What about people who say they feel better or report losing weight after discontinuing the consumption of gluten-containing foods?

Many, if not most of the gluten-containing foods most people eat are highly processed and calorie-dense, and a lot of them contain a lot of fat. The average bakery muffin has over 500 calories; bagels have 400-600 calories, a croissant can pack as many as 750 calories. Reducing or eliminating these foods will almost always result in weight loss, particularly if they are replaced by healthier and lower-calorie options like vegetables and beans.

For those who say they feel better when they don’t consume gluten-containing foods, many times this is a result of the change in dietary pattern that often accompanies gluten elimination – more whole foods, less processed junk. In other words, because the dietary pattern improves, symptoms improve and weight is lost, and the anti-grain crowd attributes it all to the elimination of grains.


Most people can include grains, including high-gluten grains, in the diet. This is good news – most people like foods like whole grain bread, pasta, and minimally processed cereals.


[1] Koerner T, Cleroux C, Poirier C, Cantin I, Alimkulov A, Elamparoc H. “Gluten contamination in the Canadian commercial oat supply.” Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2011 Jun; 28(6): 705–710

[2] Thompson T. “Gluten Contamination of Commercial Oat Products in the United States.” NEJM  2004; 351:2021-2022

[3] Cash BD, Rubenstein JH, Young PE, et al. “The prevalence of celiac disease among patients with nonconstipated irritable bowel syndrome is similar to controls.” Gastroenterology. 2011;141:1187-1193.

[4] Wahnschaffe U, Schulzke JD, Zeitz M, Ullrich R. “Predictors of clinical response to gluten-free diet in patients diagnosed with diarrhea-predominant irritable bowel syndrome.” Clin Gastroenterol Hepatol. 2007;5:844-850.

[5] Sabatino A, Volta U, Salvatore C et al. “Small Amounts of Gluten in Subjects With Suspected Nonceliac Gluten Sensitivity: A Randomized, Double-Blind, Placebo-Controlled, Cross-Over Trial.” Clin Gastroent and Hepatol September 2015;13(9):1604–1612.e3

[6] Elkan A, Sjöberg B, Kolsrud B, Ringertz B, Hafström I, Frostegård J.” Gluten-free vegan diet induces decreased LDL and oxidized LDL levels and raised atheroprotective natural antibodies against phosphorylcholine in patients with rheumatoid arthritis: a randomized study.” Arthritis Res Ther. 2008;10(2):R34.