Nutritional and Health Aspects of Sweeteners - Sweeteners: Nutritional Aspects, Applications, and Production Technology - page 349

suggested that animals, including humans, use orosensory cues from foods to signal the nutritive
consequences when eating and a sweet taste that does not signal the arrival of these consequences
may contribute to deicits in the regulation of energy balance. They also examined whether these
effects generalized to additional caloric and noncaloric sweeteners. Rats were divided into four
groups (glucose, sucrose, saccharin, or Ace K) and received ixed volumes of unsweetened or sweet-
ened low-fat yogurt daily for 14 days in addition to ad libitum chow and water. During the 2-week
diet exposure, animals that received high-intensity sweeteners gained signiicantly more weight
than animals that received caloric sweeteners. Additionally, the high-intensity sweetener groups
consumed signiicantly more total calories than the caloric sweetener groups. This data showed that
the effects on food intake and body weight gain are not directly related to the consumption of a par-
ticular high-intensity sweetener but that the consumption of high-intensity sweeteners, in general,
may disrupt energy balance (Roy et al. 2007).
11.5.7 high-Fructose Corn Syrup, energy Intake, and Body Weight
High-fructose corn syrup (HFCS) is produced from the isomerization of some of the glucose
in corn syrup to fructose. HFCS-55, consisting of 55% fructose and 42% glucose, is used in many
sweetened beverages, whereas HFCS-42 (42% fructose; 53% glucose) is used to sweeten confections.
The GI of HFCS has not been published, but the GI of cola sweetened with HFCS is 63 ± 5
(Foster-Powell et al. 2002), a igure close to that of sucrose (68 ± 5), which might be expected
because of the similarities between the sweeteners. Low-GI foods have been associated with greater
satiety than high-GI foods (Brand-Miller et al. 2002). Low-GI foods may prolong satiety between
meals, whereas high-GI foods may signal immediate satiety.
HFCS has been implicated in excess weight gain through mechanisms seen in some acute feed-
ing studies and by virtue of its abundance in the food supply during years of increasing obesity.
Compared with pure glucose, fructose is thought to be associated with insuficient secretion of
insulin and leptin and suppression of ghrelin (Melanson et al. 2008). However, when HFCS is com-
pared with sucrose, the more commonly consumed sweetener, such differences are not apparent,
and appetite and energy intake do not differ in the short term. Longer term studies on connections
between HFCS, potential mechanisms, and body weight have not been conducted. The authors
examined collective data on associations between the consumption of HFCS and energy balance,
with particular focus on energy intake and its regulation.
Some experts have implicated HFCS as a possible contributing factor to energy overconsump-
tion, weight gain, and, thus, the rise in the prevalence of obesity over the past decades (Ludwig et
al. 2001; Bray et al. 2004; Elliott et al. 2002).
Melanson et al. (2007) reported that HFCS results in increased plasma glucose and insulin,
most likely as a result of the glucose moiety. They conducted a similar study design with two
2-day visits in 30 healthy-weight young women to compare hormonal and appetitive responses
to beverages sweetened by HFCS or sucrose. The beverages were served with three meals dur-
ing the day and provided 30% of the energy intake. Energy intake was controlled on the irst day
when the test beverages were served and appetite was rated, and food intake was ad libitum on
the second day of each visit. Blood glucose, insulin, leptin, and ghrelin did not differ signiicantly
between the two sweeteners. HFCS- and sucrose-sweetened beverages produced similar ghrelin
suppression after each meal of approximately 200 pg/mL after both sucrose and HFCS trials.
Finally, no signiicant differences were seen between HFCS and sucrose in ad libitum energy or
macronutrient intakes. Appetite ratings were also similar (the one exception was a slightly greater
desire to eat after sucrose consumption). The lack of differences between HFCS and sucrose
in energy intake and appetite ratings are not surprising because of similar responses in plasma
glucose, insulin, leptin, and ghrelin, all of which have been postulated as biomarkers of energy
intake regulation.