NEW YORK, Feb 16 (Reuters Health) -- Foods containing the controversial fat substitute olestra do not cause ``clinically meaningful or bothersome'' gastrointestinal symptoms, according to a report published in the February 16th issue of the Annals of Internal Medicine.
But in an editorial, Dr. Howard Spiro of Yale University, New Haven, Connecticut, notes that in the study -- which was funded by Procter and Gamble, the makers of olestra -- one third of people ``who consumed olestra the most often or in the largest amounts had more frequent bowel movements than those who did not eat as much.''
Olestra, which is derived from edible fats and oils, is not broken down or absorbed by the body, the researchers note. The substance has been linked to abdominal cramps and loose stools in some people. The Food and Drug Administration has approved olestra for use in snack foods, such as potato chips, but the products carry a warning of these potential side effects.
But a 6-week study of over than 3,100 adults and children indicates that those who consumed corn or potato chips containing olestra had no more gastrointestinal problems than those who ate regular chips, Dr. Robert S. Sandler of the University of North Carolina at Chapel Hill and colleagues report. In either group, approximately one third of the participants reported gastrointestinal symptoms.
The findings of the study suggest that the only differences between the groups were that control subjects reported more nausea and subjects in the olestra group, on average, reported more frequent bowel movements.
Olestra consumption by study participants was sufficient to assess the gastrointestinal effects of the product, the authors say. ``Approximately half of the participants ate olestra snacks on more than half of the 42 study days; this rate of consumption in considerably higher than typical chip consumption in the United States.''
The findings ``do not substantiate anecdotal reports of severe diarrhea and abdominal pain or cramping associated with olestra,'' Sandler's team concludes. Rather, ``they show that under ordinary snacking conditions, gastrointestinal symptoms among participants who eat snacks containing olestra are no more troublesome than those associated with consumption of regular snacks containing triglycerides.''
The study authors also note that a national survey found that up to 40% of US adults may experience gastrointestinal symptoms in a given month. ``Consumers who have read (the label on foods containing olestra) or heard reports of olestra-associated gastrointestinal effects may erroneously attribute these common symptoms to olestra,'' they write.
``An important message from our study... (is that we) did not find significant digestive effects,'' Sandler told Reuters Health. ``If a person has severe symptoms after eating olestra chips, it's not due to olestra, it's due to something else.''
``People who eat lots of olestra just like people who eat lots of bran will see their stools change,'' Sandler added.
In his editorial, Spiro confesses that he is ``regarded as fat.''
``I fight weakly against additional weight gain, so I welcome olestra-containing products as potential allies,'' he writes.
But Spiro also notes that he was unable to find out how much olestra is contained in the usual daily serving.
``Because olestra is excreted in the stool, it would be prudent for persons and their physicians to know how much of the compound is being consumed each day; surely that will have some influence on the degree of gastrointestinal distress... likely to develop,'' Spiro writes.
SOURCE: Annals of Internal Medicine 1999;130:253-261.