With grocery stores stocking their shelves with gluten-free products, it may seem like a good idea to purge this protein from your diet, even if you have no clue what it is and whether you react to it. But according to Joseph Murray, a gastroenterologist with the Mayo Clinic in Rochester, Minn., there’s a lot of misinformation out there.

A 2012 report by the Mayo Clinic estimated that about 1.8 million Americans had celiac disease, a dangerous immune response to gluten. Of those, 1.4 million are unaware they have it, says Murray. (No such definitive study has been conducted north of the border, but Health Canada estimates some 300,000 people suffer from celiac disease in this country and many of them don’t know it.)

On the other side of the coin, an estimated 1.6 million Americans are currently on gluten-free diets despite never having been diagnosed with celiac disease. “It’s safe to say many people are eating gluten-free for no reason,” says Murray. So what’s up? Is going gluten-free a hipster food craze or a life-saving eating regimen? (Check out our gluten-free desserts.)

The perils of celiac disease
The bottom line: If you actually have celiac disease, you should absolutely cut gluten from your diet. This disease can have long-term and sometimes fatal health effects because your immune system basically begins to treat gluten as a harmful invader. Your body’s first line of defence is to launch a kind of overkill response that wears away the hair-like protuberances called villi that line your small intestine. (Here's how to build a gluten-free pantry.)

A properly functioning small intestine looks something like a shag carpet, with a multitude of villi aiding the absorption of nutrients into the bloodstream. But in people with celiac disease, it is more like a tile floor that lets nutrients slip by, often leading to rapid weight loss and eventual malnutrition.

Worse still, because celiac disease is an autoimmune disease (like lupus and Crohn’s disease), as it evolves it can impact other body systems, causing chronic poor health, infertility in both men and women, miscarriages, osteoporosis and cancers of the gastrointestinal tract. Unfortunately, because of the numerous ways it can manifest, celiac disease is devilishly hard to diagnose.

Silent but potentially deadly
Lori Kafato, 45, of Burlington, Ont., had bloating and stomach pain at 25 after her first child was born. Her doctor diagnosed her with irritable bowel syndrome (IBS) and suggested she eat high-fibre foods such as bran muffins. In her case, that was absolutely the wrong thing to do. Nonetheless, Lori persisted for years, trying to manage her symptoms by eating right and taking probiotics and other supplements. “It wasn’t until after I turned 40 that things really started to fall apart,” she recalls.

Lori has three daughters and was working part time in banking. By 7 p.m., she’d fall asleep on the couch, utterly exhausted. “If somebody had a cold within 10 feet of me, I’d catch it,” she says. She developed a series of infections that landed her in the hospital emergency room. She had muscle cramping during exercise, burning eyes, severe back pain and numbness in her hands and feet.

“I just felt like a complete mess,” she says. “I actually thought I was dying.”

Lori’s break came when a doctor referred her to a gastroenterologist who performed a blood test to check for gluten autoantibodies, then did a biopsy of her small intestine. The biopsy took all of 20 minutes. The conclusion: She had damage consistent with celiac disease. It just took 15 years to find it.

Lori’s experience is typical. The 2007 Canadian Celiac Health Survey found it took, on average, 12 years to get a diagnosis. That’s because celiac is a multisymptom, multisystem disease, says Shelley Case, a registered dietitian from Regina and the author of Gluten-Free Diet: A Comprehensive Resource Guide (Case Nutrition Consulting, 2008). “Some people only present with anemia. They’re told to take iron supplements,” says Case. “Or they may be told they have chronic fatigue because their joints ache and they’re tired. But no one thinks of celiac.” Women in their 50s often have symptoms that doctors attribute to menopause. And just to complicate matters further, says Murray, some people with celiac disease have no symptoms at all. “Your small intestine can be about six or seven metres long,” he explains. “Even if 10 percent of your intestine is inflamed, there’s a lot of reserve capacity.”

Unfortunately, just because you don’t have symptoms doesn’t mean there is no damage being done. Having undiagnosed celiac disease is really not good for you, says Murray. “It may take 20 to 30 years for problems to arise, but there’s a good chance they will.”

Rising rates among all ages
In 2009, Murray and a team from the Mayo Clinic published the results of a study that analyzed some 9,000 blood samples taken from Air Force recruits in the early 1950s. They were looking for gluten antibodies. The Mayo Clinic researchers expected about one in every 100 test results would be positive for celiac disease – the same proportion that exists today. Instead they found much lower rates. “We were able to show that celiac disease was very rare back then,” says Murray. “It is four to five times more common now. It’s not just that we’re better at finding it, although we are; it is a true increase.”

What’s more, although celiac was once regarded as a childhood-onset disease, that’s no longer the case. A study from the Center for Celiac Research in Baltimore, Md., followed more than 3,500 volunteers from 1974 to 2003 and found the number of people with celiac disease doubled every 15 years, and the incidence increased with age. “You can get celiac disease in your 60s for the first time, even if you’ve been eating wheat all your life,” says Murray.

Exactly why celiac disease is more prevalent now is unclear. But Murray points out that gluten is being used more frequently and in purer forms than it has been in the past. “Wheat is made to grow shorter and with bigger seeds to have a higher yield,” he explains. “It’s bred to be drought- resistant, heat-resistant, pest-resistant and responsive to nitrogen fertilizer. All those things maximize the gluten content because it’s important for its baking properties.” To top it off, purified wheat gluten is added to foods such as high-fibre bread (because it helps the fibrous dough stick together and rise) and high- protein bread (because gluten is a protein). “I think it could be overexposure at certain times, and in this very purified state,” says Murray.

Shelley Case believes the theory that celiac disease and other conditions are being caused by junky diets and an overuse of antibiotics, which are changing the bacterial composition of the gut and killing off good bacteria. (Don't miss our Gluten-Free Sandwich Bread recipe.)

In either case, it seems likely that something activates the disease. About 47 percent of the respondents to the Canadian Celiac Health Survey reported experiencing a potential trigger within six months prior to symptom onset, including severe stress (23 percent), a severe gastrointestinal infection (nine percent), a pregnancy (eight percent) and a major surgery (seven percent).

Symptoms but no disease
What complicates matters further when it comes to diagnosing celiac disease is that there are a whole new group of patients who test negative for celiac but have many of the same physical symptoms as those who have the disease. Doctors have dubbed their condition “nonceliac gluten sensitivity.”

Although there is no test for it, a July 2012 study in the American Journal of Gastroenterology confirmed the condition’s existence, albeit among a small sample of 276 patients. “We estimate about six percent of the population has nonceliac gluten sensitivity,” says Case. “However, that is still debatable. We need larger studies to find the true incidence.” Murray says that when a patient has tested negative for celiac disease but continues to have chronic belly problems for which there is no obvious explanation, he suggests trying a gluten-free diet. “If it makes them feel better, that’s great,” he says.

That said, both Case and Murray urge patients to get tested for celiac disease before going gluten-free. If you eliminate it first, then have the test, it may well turn up negative, says Murray. That’s because the celiac-specific antibodies disappear in the absence of the protein. “Then you go back to eating it and you get sick again,” he says. In addition, without a diagnosis of celiac disease, patients are less likely to be monitored for celiac-associated conditions, such as cancer and osteoporosis, and are more likely to cheat when they eat. Murray warns, “Even if you have just a bit of gluten, you can cause damage.”

If you've been diagnosed, here's how to start the process of going gluten-free.

This story was originally titled "Myths & Misconceptions About Gluten" in the May 2013 issue. Subscribe to Canadian Living today and never miss an issue!