Energy density of foods, as opposed to their sugar or fat content, is said to be a key determinant of energy intakes. Recent laboratory studies have shown that, under ad lib conditions, subjects consume a constant weight or volume of food, so that their energy intakes depend on the energy density of the diet. Because low energydensity foods provide fewer calories per eating bout, they should Ð in theory Ð lead to reduced energy intakes and therefore weight loss. However, there is some question whether energy-dilute foods are as palatable as the more energy-dense foods. Generally high energy density equals high palatability and vice versa. Intense sweeteners represent an exception to the rule, since they maintain sweetness while reducing energy density. While many studies have explored the effects of intense sweeteners on short-term regulation of food intake, fewer studies have addressed the effectiveness of intense sweeteners in reducing energy density for weight control. Issues of energy density, palatability, and satiety, as applied to intense sweeteners are the topic of this review. Descriptors: Energy density; palatibility; satiation; intense sweeteners
IntroductionHuman obesity is the outcome of excess energy intake and insuf®cient energy expenditure (West & York, 1998). Studies of dietary factors in obesity have mostly focused on intakes of sugar and fat and on the nutrient composition of the diet (Lissner & Heitmann, 1995;Bray & Popkin, 1998). At one time or another, obesity was associated with excessive consumption of fat (Lissner & Heitmann, 1995), sugar (Harnack et al, 1999), starches (Stubbs et al, 1997), or even protein (Parizkova & Rolland-Cachera, 1997). However, the percentage of energy from a given nutrient, as opposed to total calories, may not be the primary cause of obesity. The contribution of dietary fat to obesity has been sharply questioned (Willett, 1998) and it is unclear that any single nutrient is to blame. Research attention is turning toward a new dietary variable: energy density, de®ned as the amount of available energy per unit weight ). An increasing number of studies now address energy density of foods and the mean energy density of the diet Rolls et al, 1999;Drewnowski, 1998).Energy density, as opposed to the macronutrient content of foods, is increasingly viewed as the key factor in the regulation of food intake Rolls et al, 1999;Drewnowski, 1998). Under ad libitum conditions, laboratory subjects appear to consume a roughtly constant weight of food, as opposed to a constant amount of energy . In theory then, selecting foods with low energy-density ought to lead to lower energy intakes and therefore weight loss. However, not all researchers agree that the volume of food consumed is, in fact constant, or that the regulation of food intake in real life involves modulating energy density, as opposed to the weight or volume of foods.Nonetheless, lowering energy density of foods is viewed as a viable option for obesity treatment (Rolls et al, 1999). Obese women, thought to consume ex...