"People look at you like they are shocked that you can be gluten-intolerant," said Killette, a retired accountant who lives in North Raleigh. "Wheat is in everything."

Despite such reactions, Killette is among a growing group of folk who are becoming a potent consumer force.

Gluten-free menus have cropped up at restaurants. National chains such as Outback Steakhouse and Chick-fil-A have them -- online and, if you request one, on site. So does the Red Bowl Asian Bistro, which has locations in Cary and Charlotte.

Meanwhile, sales of packaged foods labeled "gluten free" are booming.

"We have doubled our sales in the past year," said David Pelfrey, assistant regional manager at Kroger.

Increasing awareness and diagnosis of celiac disease is a major factor in the trend. The recommended treatment for celiac, an intestinal disease that affects an estimated 3 million Americans -- most of whom haven't been diagnosed -- is avoidance of gluten. That includes all types of wheat, rye and barley.

The ranks of these highly motivated gluten-free consumers are buttressed by others who have wheat allergies or who have decided, for whatever reason, that gluten-free is healthier.

"There is a huge population that may not be diagnosed with celiac disease, but they know they feel better when they follow a gluten-free diet," said Cynthia Kupper, executive director of the Gluten Intolerance Group of North America, a support organization. She estimates the total market for gluten-free products encompasses 15 million to 20 million people.

Sales of gluten-free products rose from $210 million in 2001 to $696.4 million last year, according to market research firm Packaged Facts. The company projects that sales will continue to rise at a 25 percent annual clip, reaching $1.7 billion in 2010.

SPINS Inc., a market research and consulting company in the natural products arena, has tabulated more than 3,000 products labeled gluten-free.

Beer, too

That includes gluten-free beers -- barley is a basic beer ingredient -- which were deemed plentiful enough to merit their own category at this year's Great American Beer Festival in Denver. Eight beers competed, said Julie Johnson Bradford, editor of All About Beer Magazine and a columnist for The News & Observer.

Sales of gluten-free products have traditionally been concentrated in health and specialty food stores such as Whole Foods and Trader Joe's.

Whole Foods has a gluten-free bakery facility in Morrisville that produces breads, scones, pies, biscuits and other products for more than 200 of the chain's stores nationwide. The facility employs 26, up from six when it opened in 2004 and baked only for regional outlets.

"I get fabulous feedback from customers, who are so grateful for what we're doing," said facility manager Lee Tobin, who was diagnosed with celiac disease 11 years ago. He declined to provide sales figures.

Much of the growth in the sales of gluten-free products, however, is coming from traditional grocery stores and mass merchandisers such as Kmart, said Alison Tirone, SPINS' director of marketing.

Observing a gluten-free diet requires more than finding substitutes for foods that obviously contain wheat and other glutens. Gluten is a thickening agent used in a wide variety of products, including soy sauce, hard candy, pickles and jelly beans.

Knightdale resident Lisa Noto recalls that when her youngest daughter, Kristen, was diagnosed with celiac disease 14 years ago, finding gluten-free products was daunting.

"Now it has gotten so much better," she said. "The variety of products has improved. The number of companies making products has increased."

Similarly, when they ate out Kristen, now 16, used to be limited to ordering a hamburger -- sans bun -- and a baked potato.

"Now, if we go out, we usually go to a place that has a gluten-free menu," Lisa Noto said. Among the restaurants they are able to frequent are Boston Market, Bonefish Grill and Chili's.

Simon Wong, general manager of the Red Bowl Asian Bistro, which opened in March in Cary, said three or four people each week ask for the restaurant's gluten-free menu. He said he expects the menu to become a bigger draw as word spreads.

There was a time when the Harmony Farms natural food store in North Raleigh, which has a wall devoted to gluten-free products, bought virtually any available gluten-free product, co-owner Steve Long said.

Now there are so many products, the store has the luxury of picking and choosing.

Its most popular gluten-free selections are pastas made from brown rice flour or other alternative ingredients.

"The next big thing you are going to see is pre-made dinners that are wheat- and gluten-free," Long said. "We're just starting to see them."

Gluten-free and pricey

Gluten-free products tend to be pricey. Some loaves of bread cost $6 or more.

"Gluten-free products can be two to three times higher than a mainstream product," said Kupper of the Gluten Intolerance Group. She blames growing demand, higher ingredient costs and production problems stemming from stickier doughs.

For the most part, gluten-free products are produced by small and midsize companies.

The industry giants are sitting on the sidelines until the Food and Drug Administration develops a standard for labeling a product as gluten-free, according to Packaged Facts.

The FDA has proposed a standard that would allow a trace amount of gluten -- 20 parts per million, the equivalent of a crumb in a loaf of bread -- and is supposed to issue its standard in August. The Gluten Intolerance Group of North America supports the proposed standard as "appropriate and safe."

Consequently, many products on grocery shelves contain no gluten but don't advertise it. People who observe gluten-free diets have become accustomed to scrutinizing labels and, when necessary, calling manufacturers' toll-free numbers to find out whether a product is safe for them to eat.

The consensus among people who observe a gluten-free diet is that the quality of packaged foods has been upgraded considerably over the years but still has room for improvement.

"If you didn't know some of the products, you would never know they were gluten-free," Kupper said.

But that's not always the case.

Gluten-free beer "makes me appreciate barley," Johnson said. Still, she said she would drink them if she was gluten-intolerant.

Killette tried gluten-free bagels and found them inedible. "When I threw them out to the birds, they wouldn't eat it, either," she said.

Killette said she sometimes falls off the gluten-free wagon, even though she pays for it with diarrhea, constipation or a heavy dose of nausea. "I grew up a country girl," she said. "I love biscuits. Once in a while, when I can't stand it anymore, I'll have a biscuit -- or half a biscuit."

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