Olestra: Procter's big gamble.

It's every dieter's dream: potato chips and other greasy snacks that won't make you fat.

It's every public health expert's nightmare: an uncontrolled experiment on 200 million people using an unsafe food additive.

It's the new fat substitute olestra.

Last January, when the Food and Drug Administration gave Procter & Gamble (P&G) the go-ahead to start using olestra in potato chips, tortilla chips, and crackers, it did so over the opposition of dozens of public health and nutrition experts.

The fake fat, they argued, robs the body of carotenoids. Those pigments make many fruits and vegetables orange, yellow, or green and may help explain why diets high in fruits and vegetables seem to protect against cancer, heart disease, stroke, and blindness.

The FDA rejected concerns about olestra's impact on life-threatening illnesses, but the feds did require that foods made with it carry a warning--at least about "loose stools" and "abdominal cramping." Ironically, olestra's tendency to wreak havoc on your gut may be the best thing about it...if it discourages would-be eaters.

Olean--that's olestra's trade name--could be in Pringles and other foods by this summer. So you've only got a few months to decide who to believe: the independent researchers who have spoken out passionately against the fake fat or the paid-consultant scientists that P&G has trotted out to defend its $200 million gamble. Here are the main arguments for olestra. ..and the reasons they're flawed.

CAROTENOIDS

* As long as you don't eat olestra together with carotenoid-rich foods, there's no problem. "You don't eat carrot sticks with potato chips," P&G apologists are fond of saying. They point out that olestra washes more carotenoids out of the body when both are eaten at the same meal. True. But millions of people eat potato chips with their sandwiches or crackers with their soup. If those foods contain (lycopene-rich) tomatoes, (lutein-rich) romaine lettuce, or (beta-carotene-rich) carrots, for example, olestra will drag those carotenoids out of the body.

And then there are the millions who snack on chips between meals. If P&G's results on certain vitamins are any guide, between-meal snacking may wash away up to a third of the carotenoids from a previous--or subsequent--meal.

* There's no proof that carotenoids do us any good. High-dose beta-carotene pills have clearly failed to prevent lung cancer in smokers. But "over fifty studies have found, with remarkable consistency, that diets rich in carotenoids are associated with lower risk of cancer at many sites," wrote Harvard University epidemiologists Walter Willett and Meir Stampfer in a 1995 letter to FDA commissioner David Kessler.

Nor does the beta-carotene failure mean that it's safe to deplete people of carotenoids. "There is a causal relationship between the ingestion of fruits and vegetables and decreased risk of various cancers and other degenerative diseases," says Norman Krinsky, a carotenoid expert at Tufts University. "Depletion of carotenoids may be accompanied by depletion of those factors in fruit-and-vegetable diets that are protective."

So even though there is no absolute proof that carotenoids prevent disease, it's foolhardy to add something to the food supply that steals them from the body.

And olestra is one heckuva thief.

* After four weeks of eating just three grams a day of olestra (what you'd get in about six chips) with dinner, volunteers in a Dutch study had 40 percent less lycopene in their blood than people who ate olestraless food.(1) Lycopene--a carotenoid found largely in tomatoes--is a powerful antioxidant that's been linked to a lower risk of prostate cancer (see p. 12).

"I am seriously concerned about anything that would make the carotenoids and related phytochemicals in vegetables and fruits less available and effective," says Regina Ziegler, a nutritional epidemiologist at the National Cancer Institute. "Olestra, even if consumed in limited quantities, seems to have that potential."

* Eating eight grams a day of olestra --about 16 chips--with meals for two weeks led to a 20 percent drop in lutein levels in the blood of volunteers, according to P&G's own study. Lutein, along with its close cousin zeaxanthin, is found in green leafy vegetables like spinach. In 1994, Harvard's Johanna Seddon reported that people who ate higher levels of lutein and zeaxanthin were 43 percent less likely than people who ate lower levels to develop macular degeneration--an irreversible deterioration of the retina.(2)

"Anything that lowers blood levels of lutein or zeaxanthin may contribute to this serious cause of blindness," point out Willett and Stampfer.

* Olestra will be used only in a few snack foods, so it won't have much impact. Olestra is the only fat substitute that can be used at high temperatures. So if the FDA ever expands its approval to cover deep-fried foods like french fries, all bets are off. Fast food fans--many of them youngsters--aren't exactly the world's best fruit-and-vegetable eaters, so they probably start out with low levels of carotenoids in their blood. Anything that depletes them even further could be disastrous.

*If carotenoids turn out to be important, olestra can be fortified with them later. P&G is already adding vitamins A, D, E, and K to olestra. Why? Because they're fat-soluble, and olestra appears to rob the body of anything that dissolves in fat.

So even if P&G later decides to add carotenoids to olestra, how would it replace the dizzying array of promising phytochemicals that scientists are just beginning to discover in fruits and vegetables? Many will be washed out of the body by olestra.

"The first law of tinkering is that you save all the parts," says consumer advocate and Columbia University professor emeritus Joan Gussow, who was one of only five members of the FDA's food advisory committee to vote against olestra's approval last November. "With carotenoids and other phytochemicals, we don't even know what the parts are, let alone how much would be needed to restore the status quo to olestra."

What's more, by the time P&G adds carotenoids and phytochemicals, it may be too late. "The odds are that olestra's adverse consequences would not be detectable for at least several decades, during which time enormous harm could have been done," contend Willett and Stampfer.

OLESTRA & THE GUT

* Olestra only causes digestive problems when eaten to excess. About a third of the volunteers in P&G's own studies got diarrhea when they ate 20 grams of olestra a day. That's about how much you'd get in a two-ounce single-serving bag of potato chips. And in one study, levels of diarrhea were even troublesome when people ate just eight grams (16 chips) a day.

Diarrhea wasn't the only problem. Since olestra isn't absorbed as it travels through the gut, it can leave the body as a greasy liquid. P&G claims that this "anal leakage" has been solved by a new, "stiffer" version of olestra, but the company's own data show that it's not so.

What's more, people who ate moderate amounts of olestra also had to contend with stained underwear and "greasy feces." That gives a whole new meaning to the term "snack attack."

* Olestra's digestive discomfort is no worse than that caused by eating a high-fiber diet. When people switch to a high-fiber diet, they may experience gas, bloating, and cramps. But the symptoms usually subside within several days, after "good" bacteria in the gut adapt to the extra fiber. With olestra, the only way to end your tummy troubles is to stop eating it.

* Olestra will help people lose weight. While snacks made with it will be lower in calories, it won't mean a thing to the national waistline if people end up eating more chips and other snacks. And they will, if our experience with sugar substitutes is any guide. Following the explosion of artificially sweetened foods in the 1980s, sugar consumption actually rose...and obesity rates jumped by 30 percent.

"It is quite analogous to the cigarette smoker who, when offered 'low-nicotine' cigarettes, just smokes more of them," explains researcher Daniel Steinberg of the University of California, San Diego.

RELATED ARTICLE:

This Product Contains Olestra. Olestra may cause abdominal cramping and loose stools. Olestra inhibits the absorption of some vitamins and other nutrients. Vitamins A, D, E, and K, have been added.

"Olestra's warning label should also alert consumers that the fake fat may increase] the risk of cancer, heart disease, and blindness," says Harvard's Walter Willet. CSPI has asked the Federal Trade Commission to require that all advertising for products with olestra (Olean) carry the same warning.

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(1) Amer. Journal of Clinical Nutrition 62:591, 1995. (2) Journal of the American Medical Assoc. 272:1413, 1445, 1994.