Kohlenhydrate in der regulation von hunger und sättigung

Food intake is regulated by a coordination of gastric, central nervous system and adipose tissue functions. Meal ingestion activates satiety signals within 30-60 minutes to a maximum which leads to an interruption of food intake. During the following hours satiety signals decrease while hunger sensations regain increasing activity. Initial activation of satiety is mainly due to the filling of the stomach with subsequent distension of the gastric wall. This leads to activation of afferent vagal fibers which in turn stimulate anorectic hypothalamic neurotransmitters. The recurrence of hunger sensations is at least in part due to the increase of the gastric hormone ghrelin which stimulates orexigenic hypothalamic neurotransmitters. This acute post-prandial control of hunger and satiety is regulated primarly bei the ingested volume of the food with a minor contribution of the nutrient content. The energy content of ingested food has no acute effect on satiety wich means that energy intake is largely determined by the energy density of the food items. Studies in the 80ies have suggsted that carbohydrates are more satiating than fat, while protein is superior in this context compared to the other two macronutrients. These experiments have compared the individual macronutrients on an isocaloric basis, which means that ingested amounts of carbohydrates were greater than those of fat-rich food. Food intake on the basis of satiation and satiety has shown that consumption of the various macronutrients is related to volume so that a nutrient specific satiation does not exist for carbohydrates. The extent and duration of satiety as well as subsequent food and energy intake is regulated neither by nutrient-specific effects. The available data about the role of simple sugars in feeding regulation are a matter of debate and require more extensive studies considering more realistic amounts of sugar intake with adequate control experiments.