Olestra: Just Say No
For: Wellness Fact, November 2003
Things looked bad for Procter & Gamble last fall. Its fat substitute, olestra—a 25-year, $200 million investment with a troubled history—was being attacked by well-known nutrition experts, who hoped to derail government approval because of health concerns. But then in November the Food and Drug Administration (FDA) advisory panel, made up of researchers as well as industry representatives, gave olestra its okay, though with strong dissenting voices, and only for "savory snacks" such as potato chips, corn chips, and crackers (originally the application was for use in all foods). The FDA is expected to reach its final verdict soon; it usually follows the advice of its panels. So this year we’ll probably see the test marketing of snacks containing olestra. If so, don’t buy them. Olestra is a terrible idea.
Fat substitutes may turn out to be an even bigger business than artificial sweeteners. Olestra is synthesized from sugar and fatty acids. It passes through the body without being digested or absorbed, so it has no calories. It is special because, unlike other fat substitutes, it can withstand high cooking temperatures—necessary, for instance, to fry potato chips. One ounce of olestra potato chips would have no fat and just 70 calories, compared to 10 grams of fat and 150 calories in conventional chips. It is also supposed to match the "mouth feel" and flavor of fat better than the other substitutes.
Argument, counter-argument
The vocal campaign against olestra has been led by the Center for Science in the Public Interest (CSPI), a nonprofit advocacy group. Here are some of its arguments, followed by P&G’s responses:
• Olestra can deplete the body of fat-soluble vitamins, including A, D, E, and K, as well as carotenoids such as beta carotene. Carotenoids are important antioxidants, and as such may help protect against cancer and heart disease. In one of P&G’s own studies, eating 16 olestra potato chips a day for eight weeks reduced blood carotenoid levels by 50%. In another study, six chips a day lowered beta carotene levels by 20%.
P&G responds that it will fortify olestra with A, D, E, and K to make up for depletion of the vitamins. Regarding the lost carotenoids, which will not be not added, P&G says this is a problem only in "extreme" cases—if you eat olestra with every meal and at the same time as carotenoid-rich foods.
• If olestra affects blood levels of vitamin K (even if it is fortified with K), that could be dangerous for people with bleeding disorders or those taking blood thinners, since K affects blood thinning as well as these medications.
P&G states that it will add just the right amount of K to olestra, so it won’t be a problem for anyone. But P&G won’t say how much K it’s adding, so who knows?• Some animal studies found liver-cell changes that raise suspicions about a potential cancer risk.
P&G says that such liver changes in lab studies do not indicate cancer, and that long-term mouse studies have found no evidence of cancer.• There’s a high risk of diarrhea and cramping. In one study, half the subjects developed diarrhea after eating three ounces of potato chips made with olestra. Other studies found that even one ounce of chips caused diarrhea and cramps in some people. Finally, olestra can cause rectal leakage in some people, visible as yellow/orange stains on underwear.
P&G replies that in a survey of consumers, snacks containing olestra caused no more gastrointestinal problems than regular snacks. It compares the effects to what happens when people eat a lot of fiber. It must be noted, however, that fiber has numerous health benefits, while olestra does not, and that people adapt to a high-fiber intake over time, but wouldn’t to olestra. In any case, the company says it has reformulated the product to reduce the risk of rectal leakage.Want to eat mineral oil?
We are not convinced by P&G’s arguments and hope that the FDA gives it a thumbs down. The physical properties of olestra are virtually identical to mineral oil and petrolatum, depending on how these are formulated, according to Dr. Sheldon Margen, Professor Emeritus of Public Health Nutrition at UC Berkeley and chairman of the Editorial Board of the Wellness Letter. Mineral oil is a laxative and carries a warning against long-term use because of its effect on nutrients, the risk of laxative dependence, and other potential adverse effects. Over the years various scientists have experimented with fat-free cookies made with mineral oil. The cookies may have been delicious, according to Dr. Margen, but they caused gas, bloating, diarrhea, and rectal leakage.
"The evidence for potentially adverse effects from olestra is overwhelming," concludes Dr. Margen. The depletion of nutrients and other beneficial substances, such as carotenoids, from the body is especially worrisome. The claim that some of the depleted substances would be replaced in olestra is nonsense. No one knows which substances to replace, how much to replace, or how good the replacements are.
The FDA advisory panel acknowledged that foods containing olestra should bear a warning label about potential gastro-intestinal problems. The foods would need other warning labels as well. There’s probably little harm in eating a little olestra occasionally. But people eat potato chips and other salty snack foods frequently and seldom in small amounts. Kids are big consumers of these foods and are unlikely to pay attention to warning labels.
And would olestra help prevent obesity? No one knows. But since the advent of artificial sweeteners, Americans have only gotten fatter. Consumers of fake-fat foods may feel justified in treating themselves to more calories and/or high-fat foods. If you eat lots of foods containing olestra (or other fake fats) in place of grains, fruits, and vegetables, you’ll end up with more calories and fewer nutrients than before, especially since olestra actually removes nutrients from the body.
The world doesn’t need olestra.
UC Berkeley Wellness Letter, February 1996
