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The olestra molecule differs from a fat molecule in that it has six to eight fatty acids on a sucrose core, as opposed to three fatty acids on a glycerol core. The bulkier olestra molecule is not digested, absorbed , or metabolized, and thus provides no calories (Stern & Hermann-Zaidins ,1992 ). It has the same taste and texture of fat, and even retains this texture in deep frying. One ounce of potato chips with olestra contains only 70 calories, as opposed to the usual 160 calories (http://plainfield.bypass.com/%7Etwilbur/olestra.html).
The purpose of olestra is two-fold. Consumers believe they can cut calories eating products containing olestra. Since this fat substitute decreases fat intake, the result is weight loss. More importantly, less fat in a persons daily diet cuts down the risk of heart disease, cancer, and other illnesses.
Developed by Proctor & Gamble, olestra will be used in potato chips, in corn chips, in crackers, and in other snack foods under the name Olean. Consumers who are interested in purchasing olestra products should try Frito-Lays MAX line of snack foods (only sold in limited test markets in the United States). Frito-Lay MAX products will eventually be offered nationwide if test market consumers place these snacks in high demand. However, people who wish to reduce their fat intake without consuming olestra should try Frito-Lays baked and reduced fat products (http://www.fritolay.com/olestra.html).
There are some interesting drawbacks to olestra. Olestra causes diarrhea and affects the absorption of Vitamins A, D, E, and K. In essence, olestra acts like a giant sponge, taking nutrients out of the body before they have a chance to be absorbed in the intestines. "Olestra may cause abdominal cramping and loose stools in some individuals, and inhibits the bodys absorption of certain fat-soluble vitamins and nutrients," said Commissioner of Food and Drugs, David A. Kessler, M.D. ( http://www.fda.gov/bbs/topics/NEWS/NEW00524.html). In one study, almost one-half of the group reported having diarrhea, bloating, and gas disturbances after eating eight grams of olestra, the equivalent of less than the amount of olestra in one ounce of potato chips (http://plainfield.bypass.com/%7Etwilbur/olestra.html). Since olestra blocks Vitamins A, D, E, and K, these nutrients cannot protect us against disease. The FDA requires that Vitamins A, D, E, and K be added to all products with olestra. Olestra also blocks the absorption of beta-carotene. Foods rich in beta-carotene, such as sweet potatoes, broccoli, cantaloupe, and many other fruits and vegetables protect the immune system, and act as a buffer against cancer and heart disease. "Studies have shown that eating even a small snack bag of olestra-fried potato chips can reduce blood levels of beta-carotene by 60%" (http://pharminfo.com/cgi-bin/printhitbold.pl/pubs/msb/olestra2.html). However, Proctor & Gamble will not add the carotenoids to olestra because they argue that these benefits are unproven.
In a recent study in The American Journal of Clinical Nutrition (Cotton, J.R., Weststrate, J.A., & Blundell, J.E., 1996), sixteen healthy males from the University of Leeds were chosen to participate in two, two-day test sessions at the Human Appetite Research Unit. On day 1, food intake was fixed: subjects received three meals (breakfast, lunch, and dinner) containing either sucrose polyester (SPE) or control fat. On day 2, intake was at ones pleasure. In addition, none of the foods had been altered with respect to SPE. Subjects rated themselves as more hungry after eating the SPE-substituted meals than after eating the control meals. The substitution decreased fat energy from 32% to 20% and the total energy from 2700 kcal to 2300 kcal. Therefore, subjects ate significantly more the day after the SPE test day than on the day after the control day. Subjects consumed approximately 1255 kJ more the day after the low-fat, low-energy SPE test day than on the day after the control test day (Cotton, Weststrate, & Blundell 893). This evidence verifies that compensation occurred for the reduction in energy intake. Subjects not only increased their fat intake, but also their total carbohydrate intake the day after the SPE test day.
On the other hand, according to National Institutes of Health (NIH) - supported investigators, sucrose polyester "has considerable potential for weight reduction therapy in the treatment of obesity" (Anonymous 2963). In the Journal of American Medical Association, Dr. Charles J. Glueck and colleagues at the University of Cincinnati General Clinical Research Center described a double-blind study designed to predict whether sucrose polyester, when substituted for conventional dietary fat, decreases total caloric intake. The subjects in the study were ten obese patients. Baseline caloric intake was determined for each subject, and two, twenty-day study periods were established in which each patient consumed either a placebo or approximately 60g of SPE (sucrose polyester) in his/her diet regimen. In both study periods, the subjects were required to consume 60% of their baseline caloric intake through the combination of breakfast, lunch, and dinner (sucrose polyester was present in all three meals). In addition, the subjects could compensate for a caloric deficit through free-choice snack intake. "This regimen allowed subjects to increase snack calories freely to make up for the covert mealtime reduction of an average of 540 calories, which occurred when the 60g of sucrose polyester was substituted for conventional cooking fat (Anonymous 2963). During the study, sucrose polyester occurred in three different forms (See Table 1).
The results of the study showed that, while consuming sucrose polyester, the patients did not perceive more hunger and consumed 23% fewer snack calories. Both factors resulted in an average weight loss of about 0.4 lb/day. Dr. Charles J. Glueck and colleagues reported on some of the investigators other findings as well. For example, sucrose polyester significantly decreased absorption of cholesterol, and reduced dietary saturated fat content by 50%, polyunsaturated fat content by 54%, and dietary cholesterol by 25%. These reductions in dietary fat and cholesterol (in addition to caloric restriction) decreased levels of total plasma cholesterol by 10%, low-density lipoprotein cholesterol by 14%, and triglycerides by 15%.
Thus, unlike the results of the study involving nonobese males, the results of this study (involving obese patients) clearly show that olestra (sucrose polyester) can indeed affect body weight.
Studies demonstrate how olestra (sucrose polyester) affects the absorption of carotenoids. Sucrose polyester actually blocks the absorption of carotenoids needed to protect the body against chronic diseases, specifically coronary heart disease, cancer, and age-related macular degeneration leading to blindness (Weststrate 1995).
In The American Journal of Clinical Nutrition (Weststrate, J. & Van hef Hof, K.H., 1995), two studies were undertaken with two groups of volunteers, one group consuming margarine containing sucrose polyester, while the control group consumed margarine without sucrose polyester. The volunteers were requested to consume the margarine at their main meal because their main meal included vegetables, which provides a source of carotenoids. The study was conducted over a four week period, and divided in two phases, a high dose of SPE (sucrose polyester) and a low dose of SPE (sucrose polyester). The high dose group had 21 volunteers, with 11 in the SPE group, and 11 in the control group. The SPE group consumed 31 grams of margarine per day containing 12.4 grams of SPE. The control group consumed 31 grams of margarine per day without SPE. The low dose group had 53 volunteers, with 26 in the SPE group, and 27 in the control group. The SPE group consumed 7.5 grams of margarine per day containing 3 grams of SPE. The control group consumed 7.5 grams of margarine per day without SPE. The margarine and SPE (sucrose polyester) were prepared in the laboratory. At various points, blood samples were drawn from all volunteers and carotenoid concentrations analyzed. The results show adverse effects in the SPE groups.
The blood levels of carotenoids show significant reduction when consuming sucrose polyester because SPE passes through the digestive tract unabsorbed. Sucrose polyester (olestra) acts like a giant sponge taking nutrients out of the body. The high dose study shows that beta-cryptoxanthin decreased by 23%, lutein decreased by 20%, and zeaxanthin decreased by 18%. Beta-carotene decreased by 34%, and lycopene decreased by 52%. The high dose study indicates that beta-carotene and lycopene levels were severely reduced. The low dose study indicates beta-carotene decreased by 20% and lycopene decreased by 38%, which is significant as well due to the small amount of SPE administered in the low dose study.
The results of the study show that as little as 3 grams of sucrose polyester a day drops the blood levels of carotenoids significantly . This conclusion should be of concern because carotenoids are responsible for specific protective effects on the body. Seddon, M.D. et al. (1994) explain how lutein and zeaxanthin protect the eye. Low levels of these carotenoids increase the risk of developing age-related macular degeneration. "The dominant pigments in the macula are lutein and zeaxanthin, which are selectively accumulated in the retina from plasma. These yellow pigments, lutein and zeaxanthin, can filter out visible blue light, which theoretically can cause photic damage. Ultraviolet light is filtered by the cornea and lens in the anterior aspect of the eye, but visible blue light reaches the retina. Therefore, lutein and zeaxanthin might serve to protect the retina from photic damage or other oxidative insults" (Seddon, M.D. et al. 1420). Therefore, it is important to increase the intake of food high in carotenoids. Specifically, spinach, and collard greens has the most beneficial effect in lowering the risk of developing age-related macular degeneration because these vegetables contain the greatest amount of lutein and zeaxanthin. Greenberg, M.D. et al. (1996) state that beta-carotene protects against coronary heart disease and cancer, and lycopene protects against cancer as well. Research indicates that increasing intake of foods high in beta carotene, and lycopene, such as cantaloupe, carrots, broccoli, tomatoes, etc., lowers the risk of coronary heart disease and cancer. "Beta-carotene consumption, as well as blood concentration of beta carotene, is consistently associated with lower risk of cancer, particularly of the lung" (Greenberg, M.D. et al. 699).
In conclusion, this review has covered many of the important aspects, both positive and negative, of olestra (sucrose polyester). First, the study conducted at the Human Appetite Research Unit focused on the role of olestra in relation to nonobese males. The effects of sucrose polyester on these subjects were negative. Subjects not only increased their fat intake, but also their total carbohydrate intake the day after the SPE test day. In the second study, sucrose polyester (olestra) proved quite effective in weight reduction therapy designed for obese patients. When consuming sucrose polyester, subjects did not feel more hungry and even consumed fewer calories! Of course, these two factors eventually lead to weight loss: approximately 0.4 lb/day. In addition, olestra (SPE) reduced dietary fat and cholesterol. Finally, the last two studies show how olestra (SPE) blocks the absorption of carotenoids. Carotenoids are essential because they protect the body from chronic diseases, such as cancer. The results of the studies show that olestra-containing products can be a health risk and may prove to be a danger to the American public.
Proctor & Gamble is in a very unique situation. It has obtained
approval by the FDA to use olestra as an effective fat substitute. However,
many of the questions raised by the use of olestra pose further questions.
If olestra absorbs Vitamins A, D, E, and K, as well as carotenoids, what
other nutrients is it absorbing that the research has not yet shown, and
what effect will it have upon future generations? What effect, then, will
olestra have on the American public if it becomes an ingredient in bakery
products, ice cream, candy, fried foods, etc.? Because we live in a society
where "thin is in," we are surely apt to try olestra-containing
products. However, as the variety and availability of these products increases,
so too does our risk for disease. In modern-day society, most Americans
combine a fast-paced lifestyle with fast-food restaurants. Many of us do
not eat balanced meals and, as a result, we do not eat enough fruits and
vegetables. Therefore, at present, a large number of Americans have a low
carotenoid concentration level. Adding olestra to more of our favorite
snack foods would be like "adding more fuel to the fire." Fat-free
snacks have become the "craze!" Most people have a tendency to
eat a larger quantity of these foods because they are "fat-free."
Now, if olestra is added to these products, the risk for disease and malnutrition
So, is it worth the risk just to save one-half the calories per ounce of potato chips? "Just six potato chips a day can reduce carotenoids by about 40 percent," contends Dr. Walter Willet, a nutritionist at the Harvard School of Public Health. "Based on that amount of beta-carotene reduction caused by olestra, there would likely be thousands of premature deaths due to cancer and cardiovascular disease in the United States annually" (Greenberg, M.D. et al. 701).
Anonymous. The Use of Sucrose Polyester in Weight Reduction Therapy. Journal of American Medical Association. December 1982, Volume 248, No. 22, 2963-2964.
Cotton, Jacqui R., Weststrate, Jan A., Blundell, John E. Replacement of dietary fat with sucrose polyester: effects on energy intake and appetite control in nonobese males. The American Journal of Clinical Nutrition. June 1996, Volume 63, No. 6, 891-895.
Greenberg, E., Robert, M.D., et al. Mortality Associated with Low Plasma Concentration of Beta Carotene and the Effect of Oral Supplementation. Journal of American Medical Association. March 6, 1996, Volume 275, No. 9, 699-703.
Seddon, Johanna M., M.D., et al. Dietary Carotenoids, Vitamins A, C, and E, and Advance Age-Related Macular Regeneration. Journal of American Medical Association. November 9, 1994, Volume 272, No. 18, 1413-1420.
Stern, Judith S., Hermann-Zaidins, Mindy G. Fat Replacements: A New Strategy for Dietary Change. Journal of the American Dietetic Association. January 1992, Volume 92, No. 1, 91-94.
Weststrate, Jan., Van hef Hof, Karin H. Sucrose Polyester and plasma carotenoid concentrations in healthy subjects. The American Journal of Clinical Nutrition. September 1995, Volume 62, No. 3, 591-597.
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