CINCINNATI (AP) _ Comedians have had their fun joking about olestra, the zero-calorie fake fat for snack chips. Now, Procter & Gamble Co. is striking back.

Buffeted by months of mocking over stories of olestra's gastric side effects, P&G is beginning its first olestra commercials _ featuring testimonials from people who say they like olestra-flavored chips.

The spots will air initially in Columbus in conjunction with the test marketing of Pringles chips, P&G's first olestra-based product. Pringles with Olean _ P&G's brand name for olestra _ will hit Columbus shelves on Monday.

The commercials will show people who have eaten another brand of chips with olestra _ Frito Lay's Max chips _ now being tested in three other cities.

``The ad campaign captures the tremendously positive experiences with Olean chips that consumers already have had and are sharing,'' P&G spokeswoman Sydney McHugh said Monday. ``The tag line is, `Tested and approved by people like you.'''

The customers in the ads weren't paid, but they did receive money to participate in research on diet and lifestyle, P&G said.

The company won't say how much it is spending on the ads, but it has already spent about $200 million and 25 years to get olestra approved. The OK finally came this January from the Food and Drug Administration, but with some big provisos.

The FDA required P&G to put a warning label on olestra products, saying it might cause some embarrassing digestive problems.

Comics loved it.

``The reports say olestra is said to cause diarrhea and, in their words now, anal leakage,'' Jay Leno explained last week. ``So folks, when you're through with the Pringles, you might want to hang on to the can.''

Olestra is a synthetic chemical made from sugar and vegetable oil. It looks like real fat, but its molecules are too large to digest, so it passes through the body unabsorbed.