Gluten-free dieters are sprouting up all over the place. Some believe the diet will make them healthier or skinnier. Others claim a sensitivity or intolerance to gluten.

Collectively, gluten-free eaters fueled a more than $4.2 billion industry last year, and that number is expected to grow to more than $6.6 billion in 2017, according to the American Celiac Disease Alliance, a group that supports people with an autoimmune disorder in which eating gluten damages their small intestines and makes it harder for their bodies to absorb nutrients.

The gluten-free boom — much of which in recent years has been fueled by non-celiacs — even prompted the U.S. Food and Drug Administration to adopt new regulations governing what constitutes a gluten-free food.

Even as all that is happening, physicians and researchers are uncertain about whether gluten sensitivity among non-celiacs exists at all.

“The jury is still out,” said Dr. Eamonn Quigley, chief of the division of gastroenterology and hepatology at Houston Methodist Hospital. “I don’t see enough data to convince me of exactly what’s going on. I think we just don’t know.”

Many dietitians and gastroenterologists like Quigley are now recommending that non-celiac patients who say they have a gluten sensitivity — which tends to present in the form of gastrointestinal symptoms such as abdominal pain, diarrhea, constipation, bloating and vomiting — try what’s called the low-FODMAP diet.

Each letter in FODMAP (fermentable oligo-saccharides, disaccharides, mono-saccharides and polyols) stands for a complex carbohydrate that could be causing GI symptoms or irritable bowel syndrome, a disorder affecting 5 to 15 percent of people that results in GI symptoms.

While they’re digested, FODMAPs pull water into the intestinal tract, so they can be hard to digest and in some cases could be fermented by bacteria. Since research has shown IBS sufferers may be more sensitive to FODMAP foods than the average Joe, a diet low in FODMAPs could help.

Those who say they experience GI symptoms after consuming gluten products might actually be reacting to something else entirely: fructans, a type of carbohydrate in wheat, Quigley said. Fructans, also found in onions and garlic, are eliminated in a low FODMAP diet, along with fructose (found in fruits and honey), lactose (found in dairy products), galactans (beans and lentils) and polyols (sweetners and some fruits).

Quigley points to a 2008 double-blind study from Monash universiy in Australia — where the low-FODMAP diet was developed — in which patients with IBS reported significantly improved symptoms after going on the low-FODMAP diet, but little change after restricting gluten.

What could be confusing is the fact that a low-FODMAP diet does restrict most gluten from the diet, but Quigley emphasizes that eliminating FODMAPs goes well beyond gluten.

“This research suggests you start with the FODMAPs, rather than starting with the gluten-free diet and go the other way around,” he said.

Vanessa Cobarrubia, a registered dietitian who works at Bend Transitional Care, a skilled nursing facility, said the diet is still relatively new, so she hasn’t helped many clients with it yet, but she has tried it herself.

An IBS sufferer whose symptoms were worsening over time, Cobarrubia was able to turn things around after a month on the diet.

“IBS is a challenge,” she said. “There really aren’t too many cures for that, so I think it’s promising that this diet is helping so many people.”

‘A lot of detective work’

Despite the diet’s promise, Lori Brizee, a dietitian with Central Oregon Nutrition Consultants, said she also has big concerns about it. She’s not alone.

The problem is that many high-FODMAP foods, the ones people are told to cut, are actually very healthy — they’re fruits, vegetables, nuts and beans, after all — so making sure people are still getting proper nutrition from their diet can be a balancing act.

“My big worry with the FODMAP diet is that people take away too many foods that are really good for us,” Brizee said. “It’s very tricky.”

The low-FODMAP diet works by completely eliminating all high-FODMAP foods for three weeks (some recommendations say four to six weeks), and then slowly adding back groups of high-FODMAP foods one at a time, monitoring their effects carefully in a food journal. The diet is designed to be temporary. The hope is that people can pinpoint which foods irritate them or how much of those foods it takes to prompt their GI symptoms.

“It’s kind of playing a lot of detective work,” Cobarrubia said.

It’s very important that people trying the low-FODMAP diet work with a dietitian who can help them plan meals and ensure they don’t run into vitamin or nutrient deficiencies, Quigley said. The diet is so complex that oftentimes people find it difficult to stick with, he said.

As for Brizee’s clients, she wants to get them to a baseline level of health before setting anyone out on the low-FODMAP diet. For example, one of her clients suffers from significant IBS, but her diet lacked so much nutrition that Brizee wanted to put her on a healthy, balanced diet before restricting it further.

“Get rid of the soda pop, get rid of the fast food and actually eat some fruits and vegetables,” she said. “I look at everybody individually. I don’t put everybody with IBS on the FODMAP diet.”

Dietitians and doctors alike agree it’s important that anyone who has IBS see a physician before taking on a low-FODMAP diet, so they can rule out a serious disorder like celiac disease.

Quigley, who chaired a panel that released new guidelines this month on treating IBS, said physicians are only recently beginning to realize the crucial role diet plays in the disorder. In the future, the key will be looking at which IBS patients could benefit from the low-FODMAP diet, a high-fiber diet or probiotics, all of which have been shown to have positive effects.

“Even though patients have been telling us for years that food is a major trigger of their symptoms, we’ve been very slow to investigate this,” he said, “and, to be honest, it’s not easy. Dietary studies are very difficult to do.”

A handful of medications have also been shown to improve IBS symptoms, including the antibiotic rifaximin, antispasmodics and antidepressants.

Quigley said IBS sufferers should try a number of approaches, and while mixing dietary changes is OK, medications should be tried one at a time.

‘What is gluten?’

On a recent episode of the Jimmy Kimmel show, random gluten-free dieters in Los Angeles were posed the simple question, ‘What is gluten?’ None answered correctly.

Andrea Levario found the segment especially irritating. Her son was diagnosed with celiac disease in 2002 at age 3. These days, if he eats gluten, a protein found in wheat and other grains like rye and barley, he won’t be able to walk for a period of time. She thinks when people go gluten free without a legitimate reason, it trivializes the diet among those who truly need it.

While the demand has prompted a flood of new gluten-free products on the market, it has been hard to tell if they’re legitimately gluten-free, or if they’re just companies trying to capitalize on a trend, she said. At restaurants, the hype around gluten free can cause staff members to misunderstand the importance of the request when it’s made by someone with celiac disease.

“If the restaurant has had other patrons come in who say, ‘Well, I’m gluten-sensitive, I really can’t have this,’ and then they turn around and eat things that have gluten in them, then it makes the person who really does need the diet look bad,” said Levario, who serves as executive director of the American Celiac Disease Alliance.

In her case, Levario usually tells servers her son has a gluten allergy. That’s not really accurate, but people tend to understand allergies better than celiac disease. Eating gluten probably won’t send someone with celiac disease to the emergency room, but they’ll have severe GI distress, including diarrhea, vomiting and things like migraines, joint pain or lethargy.

The new FDA regulations, which took effect Aug. 5, require that foods labeled “gluten free” contain less than 20 parts per million (ppm) of gluten. A researcher with the American Celiac Disease Alliance found that foods with 50 ppm of gluten would probably be safe to eat, but 20 ppm provides enough of a buffer before symptoms would occur, Levario said.

What’s most baffling to Levario about people who follow a gluten-free diet unnecessarily is that many foods that contain gluten are fortified with vitamins, while gluten-free products are not. Additionally, gluten acts as a sticky binder that gives foods more body. Gluten-free foods tend to compensate for that with either more sugar or more fats, she said.

“They tend to be more fat-laden, and so they’re not healthier for you,” Levario said. “That’s a misperception.”

— Reporter: 541-383-0304,

tbannow@bendbulletin.com