A new study finds Olestra-based snack foods, made by Frito-Lay, Nabisco and Procter & Gamble, do not cause significant stomach and digestion problems.

From Medical Correspondent Linda Ciampa

ATLANTA (CNN) -- A new study funded by a major snack-food maker claims people who eat chips made with the fat substitute Olestra won't have significantly more stomach trouble than those who eat regular chips.

Researchers reported the findings after studying a group of volunteers who ate either Olestra-based chips whenever they wanted and wherever they wished, or ate regular chips one time at a movie theater.

The study followed 3,200 people for six weeks. Its sponsor, Procter & Gamble, is one of the manufacturers of Olestra chips.

Researchers said there were no significant differences by age or sex or in the number of days volunteers reported any type of digestive problems. The one difference they found was that those who ate the chips reported on average an additional day of more frequent bowel movements during the six weeks of the research. Those who ate the most Olestra-based chips had somewhat more frequent bowel movements than other volunteers, while those who ate the most regular chips had somewhat fewer than average, according to the study.

Olestra is marketed under the brand name Olean. Other companies that produce and promote Olestra-based products are Frito-Lay and Nabisco.

Dr. Robert Sandler, a professor of medicine at the University of North Carolina-Chapel Hill School of Medicine, conducted the study for Procter & Gamble, He said these results were expected.

Olestra is like bran and does not get absorbed by the body. Like bran, Olestra causes more frequent and softer bowel movements, Sandler said.

The new study follows research published last year in the Journal of the American Medical Association that concluded snack foods made with Olestra were no more likely to cause intestinal problems than standard chips.

Consumer groups tried unsuccessfully to block federal government approval of Olestra. They point out other studies have shown Olestra decreases the absorption of the fat-soluable vitamins A, D, E and K. Companies that use Olestra fortify their products with those vitamins.

More than 15,000 consumers have filed complaints, saying Olestra products have caused problems ranging from gas to bloody stool to cramps so severe they had to be treated at emergency rooms. The new study will appear in Tuesday's issue of the Annals of Internal Medicine.