DEBATE SIMMERS DESPITE FDA APPROVAL OF OLESTRA.

Byline: Shankar Vedantam Knight-Ridder Tribune News Wire

Olestra, a fat-free substitute for conventional fat, is within reach of America's grocery shelves, seductively dangling the promise of guilt-free snacking.

While fans praised the Food and Drug Administration's approval Wednesday of olestra as the agency's gift to thinner cooking, critics said the product causes gastrointestinal problems and robs the body of nutrients. America seems ready to lap it up, though, spurred on by doctors who worry about widespread obesity and by cultural mores obsessed with slimness.

"It promises to change the way Americans think about fat-free snack foods," said Gordon Brunner, senior vice president for research and development at Procter & Gamble, which developed the product.

Olestra will be sold under the brand name "Olean" to companies that make snacks. Customers can expect grocery aisles to carry such products as potato chips, tortilla chips and crackers cooked with Olean and marked with a special logo.

Olestra may eventually be used to make sweet snacks like cookies and brownies, although Wednesday's FDA approval is limited to salty snacks. Americans eat more than 5 billion pounds of snacks every year, according to the company.

Chemically speaking, olestra is fat with a difference. It is made in such a way that our digestive systems can't absorb it. It is therefore excreted undigested, leaving the body with less gooey fat, but also causing underwear stains and gastric trouble along the way.

While the FDA's approval after an eight-year investigation endorsed olestra's safety, it came with a caveat to customers:

"Olestra may cause abdominal cramping and loose stools in some individuals, and inhibits the body's absorption of certain fat-soluble vitamins and nutrients," said FDA Commissioner David Kessler said in a news release announcing the agency's approval.

Under the terms of the approval, Procter & Gamble will add vitamins A, D, E and K to olestra, which should prevent it from stealing those nutrients from the body.

But the fat-substitute also reduces the body's absorption of carotenoids, nutrients found in carrots, sweet potatoes, green-leaf vegetables and some animal tissue: The FDA has asked the company to monitor consumers for adverse health reactions.

Procter & Gamble dismisses such fears. Olestra has taken the company some 25 years - and $200 million - to develop, and its scientists say it is safe, and that the potential benefits from reducing fat in Americans' diets will far outweigh any side effects.

"While this new ingredient is not a panacea, our research suggests it may make it easier for people to reduce fat in their diets," said John Foreyt, director of the Nutrition Research Clinic at the Baylor College of Medicine, in Houston, Texas, at a Wednesday teleconference organized by the company.