CHAPEL HILL - Anecdotal reports that olestra-based potato and corn chips upset people's stomachs and digestion appear to be unfounded, according to a new scientific study.
The U.S. Food and Drug Administration approved the non-absorbable, non-caloric fat substitute for use in snacks in January 1996 and reviewed its approval last June. A report on the new study is being published Tuesday (Feb. 16) in the Annals of Internal Medicine, a medical journal.
"Olestra is composed of sucrose, which is table sugar, and soybean oil," said Dr. Robert Sandler, professor of medicine at the University of North Carolina at Chapel Hill School of Medicine. "Olestra is not digested or absorbed and passes through the gastrointestinal tract essentially unchanged.
"There's been a lot of interest in it because it allows people to eat certain snacks with fewer calories from fat," he said. "Interest also is high because of anecdotal reports in the past year or so saying it caused unpleasant and sometimes painful symptoms such as diarrhea and abdominal cramping."
What is perplexing about the reports is that they conflict with extensive clinical testing, said Sandler, study principal investigator and co-director of UNC-CH's Center for Gastrointestinal Biology and Disease. They also contradict a recent large study in which people consumed a single serving of olestra-based chips in a movie theater.
The new research involved recruiting more than 3,200 volunteers to eat either regular corn and potato chips or those made with olestra for six weeks and to keep records. They recorded how much they ate and whether they suffered any symptoms.
Participants, who lived in Phoenix and St. Petersburg, Fla., received up to eight free bags of chips per household once a week for six weeks. They did not know which bags contained the fat substitute, and neither did the researchers until the study closed.