You've been hearing about them for years, and now they're on their way to a supermarket near you: fat-free potato chips, crackers and other savory snacks.

The Food and Drug Administration gave its regulatory blessing to olestra - the key to these products' being fat-free - in 1996; now, after nearly a year of test marketing in selected U.S. markets, Procter & Gamble and Frito-Lay have announced that these snacks will be available nationwide by summertime.With tens of millions of American consumers hyperphobic about fat (humorist Dave Barry once quipped that the most effective way to get people to shun cigarettes would be to label them "contains fat"), the debut on the market of olestra products should be cause for universal celebration.

But alas: Before we can enjoy these almost guilt-free goodies, we must maneuver through the frightening and confusing miasma of misinformation being spread by a cadre of self-appointed consumer advocates. These chip-chasing killjoys have likened olestra to dog food; have hired airplanes to fly low over test-market cities trailing banners bearing the message, "Sick? Call 1-800-Olestra"; have postulated that olestra-related abdominal cramps will cause pilots to crash; and generally have characterized this breakthrough in food technology as Public Health Enemy No. 1.

So what are the fictions being spread about olestra - and what are the facts?

Fiction: Olestra has not been tested adequately.

Fact: Olestra's manufacturer has been analyzing it for some 25 years; and more than 150 studies to date support olestra's safety - studies that included hundreds of controlled clinical trials involving thousands of men, women and children. Furthermore, the manufacturer currently has post-marketing studies of the health effects of the products in process. Thus, in the unlikely event that any unpredicted health effects appear, they will quickly be picked up and reported to the FDA.

Fiction: Eating olestra snacks will give you diarrhea.

Fact: Olestra does not cause diarrhea - a serious, potentially life-threatening condition involving significant water loss and irritation of the digestive tract.

What olestra does is add non-absorbable bulk to the diet. Thus, if someone eats olestra in large-enough amounts, it can have the temporary gastrointestinal effect of causing softer or looser stools (an information label on olestra-containing products notes this possible effect). But studies do not show a pattern of widespread complaints after the consumption of olestra snacks.

Fiction: The new chips rob your body of essential vitamins and other nutrients.

Fact: There is no evidence that olestra imperils nutrition.

First, although it is true that olestra products potentially could "steal" fat-soluble vitamins from other foods, this question of vitamin absorption has already been addressed by olestra's manufacturers. All four fat-soluble vitamins - A, D, E and K - are added to olestra snack foods during the manufacturing process. Thus fortified, the olestra molecule has no "room" to pick up additional fat-soluble vitamins from foods to carry them out of the body - so there is no net loss of vitamins. Problem solved.

Second, it is also true that if you eat olestra-containing foods at the same meal as, say, carrots, you may diminish your absorption of a group of chemicals known as "carotenoids" - a group that includes the substance beta carotene, which has been mentioned as a possible anticarcinogen.

But any claim that eating olestra chips will cause increased risk of cancer or other chronic disease assumes that evidence exists that carotenoids offer protection from these diseases - which is not the case.

Fiction: Olestra has no benefits.

Fact: While there is no evidence that eating foods made with olestra will help you lose weight, olestra clearly does offer a benefit: choice. With the advent of olestra, snackers will be able to elect to have their snacks with or without fat.

Olestra has been "on trial" in the media for over a year; but during that time the "defendants" - the olestra-containing fat-free snacks - have not been widely available. Soon they will be. With the picnic-and-cookout season almost upon us - and given that olestra has been proved to be inherently safe - the time has come to let the chips fall where they may - which is to say, wherever and however the consumer decides.