Is it dangerous to self-diagnose a gluten-free diet?

One morning last fall, Erin Warhol began her day by reading a magazine article about gluten intolerance. What she read stopped her from eating her typical breakfast of two slices of whole-wheat toast.

"I saw that this was something I needed to explore," said the 48-year-old Stillwater woman. "I passed on the bread, and within 48 hours I felt a dramatic difference."

For people diagnosed with celiac disease, consuming gluten — a protein found in wheat and a few other grains — creates stomach misery and sometimes permanent intestinal damage.

It's estimated that just 1 percent of Americans have the autoimmune disorder, while another 6 percent of the population is considered gluten-sensitive.

Yet the number of people seeking gluten-free alternatives is skyrocketing. Restaurants and food producers are feeding the demand by making room on menus for new items and adding wheat-free products to grocery stores. At the same time, some celebrities have been razzed for promoting the trend as a dieting option.

Clearly, gluten has people's attention.

"More patients are coming in with this as a concern," said Dr. Cynthia Sherman, a gastroenterologist at Minnesota Gastroenterology. "They've Googled it and self-diagnosed."

Sherman said that the first step she takes when gluten intolerance is suspected is to order a blood test. She often then performs what she calls the gold standard — an endoscopic biopsy of the small bowel. It's an outpatient procedure, which takes 15 minutes and requires no laxatives.

The biopsy shows whether the villi, the microscopic finger-like structures that line the small bowel, are flattened and damaged, a sure sign that the patient has celiac disease.

"This damage limits their absorption of nutrients," Sherman said. "They could be eating the healthiest diet available, but getting none of the benefits."

Eliminating gluten can allow the villi to heal and return to normal. Sherman said that some people alter their diet, feel better and move ahead, without seeing a physician. She called this a dangerous solution.

"If it is celiac disease, going gluten-free makes it difficult to establish the diagnosis," she said. "By eliminating gluten, the lining can heal and return to normal so it looks like they don't have the disease. But this is a lifelong issue with long-term health ramifications. It should be diagnosed by a doctor, and the patient should be followed by a health practitioner."

"They start eating gluten-free products and they feel better. They might drop weight and have fewer stomachaches or less joint pain. But then they feel worse again," Denton said.

"They are eating gluten-free products, but when wheat is removed, it is often replaced with corn byproducts, and many people have a corn sensitivity, too. All of a sudden they're reacting to that."

Self-diagnosing is one thing. Dieting is another. The tabloids drive Amy Leger crazy. She shudders when she sees stories about celebrities suggesting that a gluten-free diet is Hollywood's newest get-thin secret.

"People see that and think, 'Maybe that's the diet I should be on,' " said the Blaine mother of two. "It creates confusion about how serious this is for people with celiac disease."

Leger got a crash course in the devastating effects of gluten intolerance when her daughter Emma, now 14, developed extensive health problems around her first birthday.

After a series of false starts, celiac disease was diagnosed.

"She was gluten-free within the week. The crying stopped and we had our baby back," Leger said. In the intervening years, Leger started The Savvy Celiac, a website devoted to the challenges of living with the disorder.

For those with celiac disease, even a speck of gluten can lead to inflammation and intestinal damage (such as chronic diarrhea, osteoporosis, infertility and, rarely, cancer of the small bowel).

It's not enough for them to eat gluten-free toast; they must also make sure it pops out of a toaster not used for bread containing wheat. To avoid cross-contamination, they must eat food cooked in alternate pots and pans, stirred with different utensils.

That's where the celebrity endorsements of the slimming powers of a gluten-free diet can create confusion.

Warhol, the Stillwater resident, made an appointment to see her physician shortly after she ate those last two pieces of toast. The doctor gave her a blood test, which came back negative.

"Together we decided that since this was working, I should stick with it," she said. "What I know for a fact is that when I eat gluten, my body doesn't feel good."

There is no shortage of information for consumers seeking information about food allergies and sensitivities. "Wheat Belly," a book that promotes eliminating gluten, is a fixture on the New York Times Advice, How-to and Miscellaneous bestseller list.

Nutritional Weight and Wellness, a St. Paul-based nutrition education company, began offering a class called "Going Gluten Free the Healthy Way" last year; it quickly became the most popular course of the dozen classes on the roster.

"Everyone knows someone who feels better because they've taken gluten out," said Denton. "People will do this on their own. They might feel better, but they don't always know what they are doing."