To Your Health
The Pros and Cons of the New Artificial Fat Olestra


by Paulette Avery, R.N., M.S.N.


Olestra, an artificial fat developed by Proctor & Gamble (P&G), last month won approval from the Food and Drug Administration (FDA) for use in salty snack foods such as potato chips and crackers. Will olestra help Americans cut back their fat intake and lose weight, or will it become another health hazard? Read on and decide for yourself.

Olestra is a synthetic chemical compound of sugar and vegetable oil with physical properties almost identical to mineral oil or petrolatum. It looks and apparently tastes like natural fat, but because its molecules are too large to digest, it passes through the digestive system without being absorbed. So when you eat olestra, your body doesn't absorb either fat or calories from it. And unlike other fat substitutes, it can withstand the high temperatures needed for frying foods. For comparison, an ounce of regular potato chips contains 10 grams of fat and about 150 calories. Chips fried in olestra contain no fat and only 70 calories.

Olestra sounds too good to be true, and according to its critics, it isn't good at all.

The Center for Science in the Public Interest (CSPI), the nonprofit advocacy group that has warned us of the fat content of many of our favorite foods, fought against FDA approval of olestra. And the University of California at Berkeley Wellness Letter titled the lead article in its February issue, "Olestra: just say no."

Here are their concerns. First, olestra can deplete the body of carotenoids, such as beta carotene, and fat-soluble vitamins, including A, D, E, and K. One study by P&G found that eating 16 olestra potato chips a day for eight weeks reduced blood carotenoid levels by 50 percent. Eating just six chips a day, according to another study, lowered beta carotene levels by 20 percent. So eating olestra may reduce the benefits from other healthful foods we eat.

Second, some of the studies of olestra found liver-cell changes that some experts say raises suspicions about possible cancer risk. A third major concern relates to possible side effects from eating olestra, which include diarrhea, abdominal cramping, and rectal leakage. One study found that half the people who ate three ounces of olestra chips developed diarrhea. In other studies, some subjects had cramps and diarrhea after eating just one ounce of olestra chips. Rectal leakage, visible as yellow or orange stains on underwear, also occurred in some people who ate the fat substitute.

Proctor & Gamble, who spent 25 years and $250 million developing olestra, responds that their product is safe. To counteract the problem with depletion of vitamins, P&G will fortify olestra products with these vitamins. They say depletion of carotenoids is a problem only in extreme cases, that is, only for people eating olestra with every meal and with carotenoid-rich foods. Carotenoids will not be added.

The P&G response to the cancer concern is that the liver changes associated with eating olestra don't indicate cancer, and no cancer was found in long-term studies with mice. As far as the intestinal side effects, P&G says their consumer surveys indicated no more problems from eating olestra than those caused from eating regular snacks. They compare the intestinal problems to the effects of eating a lot of fiber.

A second proponent of olestra is Robert Kowalski, author and publisher of The Diet-Heart Newsletter. He agrees with consumers who found olestra chips tasty and superior to baked fat-free chips. He also sides with scientists who consider olestra safe for human consumption in moderation, and believes the benefits of reduced fat intake outweigh any possible problems with olestra.

After reading all this information, I don't plan to eat foods containing olestra. To me, the real or potential risks from olestra seem greater than any benefit I might get from a slightly lower fat intake. I believe, in general, we are better off eating natural foods and avoiding artificial ingredients. I also wonder whether vitamin additives in olestra foods will be absorbed. If olestra isn't digested, maybe the vitamins added to olestra foods won't be either. Finally, as the U. C. at Berkeley Wellness Letter points out, Americans have only gotten fatter since the advent of artificial sweeteners. Will eating olestra reverse the trend? I doubt it.

Paulette Avery is a registered nurse and a freelance writer specializing in health issues.