IFIC Review on Intense Sweeteners Effects on Appetite and Weight Management Reprinted from Food Insight May 1992 Maintaining a healthy weight isn't easy. But according to major health experts, doing just that may decrease one's chances of developing serious, chronic health problems. Achieving and maintaining a healthy weight is one of seven "Dietary Guidelines for Americans," recommended by the U.S. Department of Agriculture (USDA) and the Department of Health and Human Services.1 Although it is important to avoid being too thin, most Americans today are fighting a "battle of the bulge." Roughly 25 percent of all American adults are overweight, thereby increasing their risk of developing high blood pressure, heart disease, stroke, diabetes, certain cancers and other illnesses.1-3 Unfortunately, there are no simple formulas or quick solutions to weight loss. But most people can successfully manage their weight by improving their lifelong exercise and eating habits. A sensible weight control program includes regular physical activity and reduced consumption of foods high in calories. A steady loss of one-half to one pound a week is recommended, rather than crash diets or other extreme approaches that severely limit amounts or types of foods. Low-calorie sweeteners can play a useful role in helping persons to maintain a healthy weight by providing good-tasting alternatives to foods and beverages typically higher in calories. According to The American Dietetic Association, "Even though sweeteners do not contribute to the nutritional value of the diet, they do have a role in an otherwise well-balanced diet for persons who choose to use sweeteners."4 The Institute of Food Technologists also has concluded that, "attractive, good-tasting, low-calorie, low-fat foods . . . and ingredients can fit into a nutritionally balanced weight loss/weight control regimen."5 Although scientific testing of intense sweeteners is extremely complex, significant progress has been made in recent years in studying their impact on appetite and body weight. This review highlights major studies in the field and summarizes their implications for weight management. Because of its widespread use and its ability to replace sucrose and maintain study blind conditions, most investigations have involved the low-calorie sweetener aspartame. Weight Maintenance/Weight Loss High-intensity sweeteners can replace nutritive sweeteners in most foods at a caloric savings of approximately 16 calories per teaspoon. Thus, caloric reduction may be achieved when low-calorie sweetened foods and beverages are substituted for their full-calorie counterparts. Questions arise, however, when one considers whether sweetener users change their eating patterns. In pioneering work at Columbia University, Porikos et al. conducted three separate studies in which volunteers were housed on a metabolic ward for up to three weeks with the stated purpose of doing blood and other tests.6-9 The protocols varied only slightly in duration and volunteers' gender and weight status. During a baseline period, subjects were allowed to eat as much sugar-sweetened food as they liked. Researchers then covertly substituted aspartame for sugar in a variety of foods and beverages eaten ad libitum by the patients. In all three studies, volunteers consumed approximately 15 percent fewer calories over time than on their baseline diets. Tordoff and Alleva recently examined whether low-calorie sweeteners influence food intake and body weight in free-living, normal-weight men and women.10 For three weeks, subjects were required to consume 1.2 liters daily of regular or aspartame-sweetened soda or to abstain from drinking soda completely. Subjects also were not informed as to the caloric content of the soda being consumed. Results showed that individuals drinking diet sodas consumed significantly fewer calories than those drinking regular sodas or the control group, which drank no sodas at all. Weight status was unchanged in females, while males lost a small amount of weight. While subjects in the aforementioned studies were unaware of the caloric content of the foods and beverages being consumed, in real life, people do know when they are eating low-calorie sweetened foods. Thus, it has been suggested that individuals may knowingly overcompensate for such products by eating other calorically-dense foods; for example, consuming a diet soft drink with a piece of cake. An indirect way to determine whether use of intense sweeteners results in caloric savings is to examine food intake records from national nutrition surveys. Using USDA nutrition survey data, Smith and Heybach compared the caloric intake records of persons consuming aspartame-sweetened foods and beverages with caloric-intakes of non-aspartame users.11 Aspartame users consumed an average of 165 fewer calories per day than non-users. Female aspartame users aged 35 to 50 years consumed 215 fewer calories per day than their study counterparts. Kanders et al. measured weight loss, perceived feelings of energy and well-being, and other "quality of life" parameters among 59 free-living, obese men and women who were knowingly on a weight-control program for 12 weeks.12 The experimental group was encouraged to use intense sweeteners, while the control group was told to avoid all such products. Both groups participated in a weight loss strategy that included support groups, behavior modification and exercise instruction. Participants consuming aspartame-sweetened foods reported increased energy levels and positive feelings of well-being. Although there were no significant differences in weight loss between the experimental and control groups, females using aspartame-sweetened products lost slightly more weight on average. The researchers concluded that aspartame facilitated the dieters' compliance and made weight loss more pleasurable by providing sweet foods without the calories. Preliminary results of a one-year follow-up study also indicate that aspartame does not increase weight and facilitates weight loss and maintenance when the intense sweetener is substituted for sugar.13 Mattes gave adult non-dieting volunteers equicaloric breakfasts of unsweetened cereal or cereal sweetened with sucrose or aspartame for five days, during which hunger and energy intake were monitored.14 Neither aspartame nor sucrose alone significantly affected hunger ratings, intake of the next meal, daily calories consumed, or food selections. Although half of the 24 subjects were aware of the caloric content of the cereal, it did not significantly affect their intakes. In an epidemiological study, Stellman and Garfinkel found that saccharin users gained an average 0.6 to 1.5 pounds more than non-users over the course of a year.15 However, this widely-publicized retrospective study was originally designed to examine cancer incidence and not weight, and had many other methodological problems. For example, the investigation failed to determine subjects' caloric intakes or their exercise habits; relied on subjects' memory to determine weight changes; and excluded women who had followed a weight-loss regimen. Furthermore, it is possible that the weight gain of saccharin users, which was statistically significant but biologically irrelevant, might have been greater without the use of the intense sweetener. Low-Calorie Sweeteners and Appetite It also has been suggested that low-calorie sweeteners may stimulate appetite, thereby increasing food intake and promoting weight gain. To test such a hypothesis, studies have been conducted using intense sweeteners in both foods and beverages, and in capsules. Food and Drink Studies. Blundell and Hill of the University of Leeds, London, reported in 1986 that persons consuming highly-sweetened solutions perceived themselves as hungrier than when consuming water alone.16 Although it drew widespread media attention, the study relied only on subjects' hunger ratings and did not measure their actual food intake, which is considered essential by psychologists and other obesity experts. The impact of having persons consume aspartame in unflavored solutions, rather than in familiar and palatable beverages such as diet drinks, also has been questioned. Blundell and colleagues conducted a subsequent study using solutions sweetened with aspartame, saccharin and acesulfame-K.17 Although increased appetite ratings were again observed for all three-types of solutions, there were no increases in actual food intake when measured one hour later. Birch et al. studied the effects of an aspartame-sweetened beverage on appetite and food intake in 2-to-5 year old children.18 Intake of various snack foods offered ad libitum was measured at several intervals up to one hour after consuming the solution. Snack consumption was decreased thirty minutes after drinking the aspartame-sweetened beverage as compared to those who drank water. A similar study of 9-to-10 year old children was conducted by Anderson et al. at the University of Toronto.19 Fruit-flavored drinks containing sodium cyclamate, aspartame, or sucrose were given, followed by a buffet lunch 90 minutes later. Aspartame did not affect hunger or food intake when compared with sodium cyclamate or sucrose-sweetened drinks. Several studies of adults also have shown that familiar aspartame-sweetened beverages do not affect short-term appetite or food intake when consumed before lunch or with meals as compared to water.20,21 Black et al. tested the effects of various volumes of aspartame-sweetened soft drinks on hunger ratings and food intake in adult males.22 Consuming 280 milliliters, or one can of diet soft drink, had no affect on appetite or food consumption compared to mineral water. However, consuming two cans of diet soft drink significantly reduced appetite ratings, but not actual food intake. A follow-up study revealed that total volume of fluid consumed, not aspartame, was responsible for suppressing short-term hunger in adult males.23 Rolls et al. covertly substituted aspartame for sugar in gelatins and puddings, creating a difference of about 200 calories between the two types of foods.24 Non-dieting, normal-weight adults were given large portions of either a regular- or low-calorie pudding or gelatin dessert to eat ad libitum. All individuals ate similar weights of the regular or reduced-calorie desserts. Awareness of the foods' caloric content did not affect appetite or food consumption from a buffet offered two hours later. Capsule Studies. It also has been suggested that intense sweeteners may alter food intake by bypassing the sweet taste and affecting certain enzymes involved in appetite regulation. Blundell and colleagues found that subjects consuming aspartame (235 or 470 milligrams) in capsules consumed less food than when taking a placebo capsule.25 However, other studies involving encapsulated aspartame at much higher doses have not replicated such findings. Anderson et al. administered aspartame capsules with water 60 to 105 minutes before lunch and found no effect on food intake or ratings of mood or hunger.26, 27 Leon and Hunninghake gave healthy adults aspartame or placebo capsules daily for 24 weeks as part of a long-term aspartame safety study.28 Body weights of those taking the aspartame capsules did not differ significantly from baseline after six months. Implications for Weight Management A variety of studies in both controlled laboratory environments and free-living populations indicate that low-calorie sweeteners do not have a paradoxical effect on appetite and can produce a caloric deficit that can result in weight loss. In a comprehensive scientific literature review, Rolls concluded that "Intense sweeteners have never been found to cause weight gain in humans. . . Although several investigators have reported increases in rating of hunger associated with aspartame, most have found that aspartame is associated with decreased or unchanged ratings of hunger."29 In the end, losing or maintaining a healthy weight depends on the individual. No scientific research will definitively prove that consuming any particular type of sweetener or food will make people lose weight, apart from other lifestyle and motivational factors. Successful weight management involves a multidisciplinary approach of diet, exercise and behavior management.2,30 No product, approach or diet plan alone can be successful. Low-calorie sweeteners are not a panacea. They do, however, enable a wide range of food choices that can aid individuals in managing their caloric intake. Because intense sweeteners provide the pleasure of sweetness, they can facilitate compliance to calorically-restricted weight loss regimens. Within a sensible weight management program, low-calorie sweeteners can play an important role in helping Americans win the "battle of the bulge." References 1. U.S. Department of Agriculture and U.S. Department of Health and Human Services. (1990). Nutrition and Your Health, Dietary Guidelines for Americans. 3rd ed. Washington, DC: US Government Printing Office. 2. The Surgeon General's Report on Nutrition and Health. (1988). Washington, DC: US Department of Health and Human Services; DHHS (PHS) publication 88-50211. Reprinted from the International Food Information Council Foundation, 1992

Home	The Library Catalogue
Books	Health Links

LinkExchange Member

Free Home Pages at GeoCities