LAS VEGAS — While food manufacturers have focused on improving the texture and taste of gluten-free products, they also may need to improve the products’ nutritional profiles, said Shelley Case, a registered dietitian and author of “Gluten-Free Diet: A Comprehensive Resource Guide.” She spoke Sept. 27 at a panel presentation sponsored by the Grain Foods Foundation during the International Baking Industry Exposition in Las Vegas.

According to Packaged Facts, the gluten-free market could surpass $2.6 billion by 2012. Wheat and several other grains contain gluten. People with celiac disease must avoid gluten.

Many gluten-free products are made with white rice flour, tapioca, corn and potato starch, Ms. Case said. When compared to enriched white flour and whole wheat flour, these alternatives may be lacking in protein, fiber, iron, calcium and other vitamins and minerals, she said. Few studies have examined the nutritional status of people who follow a gluten-free diet.

Many gluten-free manufacturers are not enriching their products, even though government regulations in the United States and Canada allow it, Ms. Case said. Pure, uncontaminated oats show promise as a healthier gluten-free ingredient, she said, since research has shown a majority of people with celiac disease are not affected by uncontaminated oats.

Glenn Gaesser, a professor at Arizona State University, and Sylvia Melendez-Klinger, a registered dietitian and founder of Hispanic Food Communications, also were on the panel. They both are members of the G.F.F. Scientific Advisory Board.

Dr. Gaesser said contrary to perception, carbohydrates and sugar are associated inversely with body weight. To prove his point, he cited studies appearing in such publications as Obesity Reviews, The American Journal of Clinical Nutrition and The Journal of the American Medical Association.

In one study, people with the lowest whole grain intake had on average a body mass index (B.M.I.) of 26.7 while people with the highest whole grain intake had on average a B.M.I. of 25.8. For refined grains, people with the lowest intake had on average a B.M.I. of 25.8 while people with the highest intake had on average a B.M.I. of 26.1. Cutting out refined grains thus would allow a person to lose 1.5 lbs per year, Dr. Gaesser said.

“Would they be terribly excited about that? Probably not,” Dr. Gaesser said.

Portion control ranks as a problem for the Hispanic population, Ms. Melendez-Klinger said. Eating large portions is acceptable.

“It is a mound of plantains,” she said. “It is a mound of tortillas. It is a mound of rice. And it is okay.”

Ms. Melendez-Klinger said subsidizing whole grains, enriched grains and fresh fruit and vegetables in schools would address Hispanic health problems as would announcements made on TV.

Hispanic women also need to be more aware of the folic acid content of enriched grains, which may aid in preventing neural tube birth defects. Hispanic women are 1.5 to 3 times more likely to have children with neural tube defects, she said.