BELLEVUE, WASH. — Gluten-free diets in the long term will be more reminiscent of fad diets like low-carbohydrate diets, according to a Sept. 17 webinar from The Hartman Group, Bellevue. While gluten-free diets eventually may fade among mainstream consumers, a small, permanent marketplace for people with celiac disease will continue to exist, according to the webinar titled "Gluten-free: Context, Insights & Predictions."

People with celiac disease must follow gluten-free diets. While about 1% of Americans have the disease, The Hartman Group research shows a little more than 13%, or about 40 million Americans, currently are interested in gluten-free products. The data was gathered from a nationally representative sample of 1,730 U.S. consumers in July.

The Hartman Group divided Americans interested in gluten-free products into five sub-categories. Two sub-categories, consumers with celiac disease and consumers who are gluten-intolerant, will see a slow growth in number through the year 2020 as improvements are made in ways to identify people with those problems.

Interest in gluten-free products among the other three sub-categories eventually will fade, according to The Hartman Group. The three sub-categories include ascetics who avoid processed foods, health and wellness followers and fad dieters who flock to a diet like it is a "flavor of the month."

Mainstream marketing opportunities do exist in the short term for gluten-free products, according to The Hartman Group, although people give different reasons for choosing gluten-free products. According to the company’s research, 39% listed digestive health, 33% listed nutrient value and 25% listed weight loss.

Consumers, upon learning more about gluten-free products, may choose products that are naturally gluten-free instead of products that need other ingredients, such as starch, to make up for missing gluten, such as that found in wheat.

Ethnic food categories such as Indian, Thai, Mexican and Middle Eastern may offer more naturally gluten-free foods. Nutritionists, when offering advice to people with celiac disease, often mention the "Super 6" gluten-free ingredients in quinoa, amaranth, millet, teff, buckwheat and sorghum, according to The Hartman Group.