Nutrient Depletion

    The long ester chains on olestra that keep it from being absorbed in the Gastrointestinal (GI) tract can dissolve other lipophilic molecules, preventing them from being absorbed as well.  This poses a problem for the fat-soluble vitamins (A,D,E, and K) and carotenoids.  Olestra only affects these nutrients when they are in the GI tract at the same time; it does not deplete nutrients that have already been absorbed by the body.
    Additionally, there are worries that people taking anticoagulant drugs like Coumadin, which work by inhibiting vitamin K-dependent clotting factors, could be adversely affected by eating products containing olestra.  People taking Coumadin must avoid major fluctuations in their level of vitamin K.
    To avoid these potential nutritional problems, the FDA requires that olestra be fortified with vitamins A,D,E, and K.  By already having the vitamins attached to olestra, it cannot dissolve any more of those vitamins in the GI tract.  The possible effects on Coumadin activity was taken into consideration when the amount of vitamin K added to olestra was established.
    Carotenoids are molecules found in plants and some bacteria that act as accessory pigments in photosynthesis.  They have a lipophilic, linear polyene structure that makes them olestra-soluble.  Some carotenoids function as precursors to vitamin A (retinol) in the body.  There is much epidemiological evidence  linking carotenoids to a decreased risk of many cancers, heart disease, obesity, and macular degeneration.  There also exists, however, a study demonstrating a higher occurance of lung cancer in smokers who took beta-carotene.  Because the exact function of carotenoids in disease prevention remains unclear, the FDA has not required them to be added to olestra as well.

Digestive Effects

    Because olestra passes through the body without being metabolized in any way, it can effect gastrointestinal function in a manner similar to other undigestible material like fiber and cellulose.  The major difference between the effects of olestra and those of fiber and cellulose is that the body can't adjust to olestra.  Any GI symptoms remain as long as olestra continues to be eaten.  The severity of the symptoms increases with the amount of olestra consumed, but differs from person to person.
    The Centers for Science in the Public Interest (CSPI), quite possibly the most vehemently anti-olestra group in existence, list a cornucopia of potential GI disturbances associated with olestra.  P&G, on the other hand, conducted a study in January 1998 that essentially exonerated olestra.  It indicates that chips made with olestra no more likely to cause GI disturbances than those made with normal fats.  The FDA requires products made with olestra to have a label stating, "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."

    For CSPI's list of reasons "why no one should eat products that contain olestra," click here.
    For Procter & Gamble's FAQ's on olestra, click here.
    To return to the main olestra page click here