Sensory-specific satiety

Sensory-specific satiety is a sensory hedonic phenomenon that refers to the declining satisfaction generated by the consumption of a certain type of food, and the consequent renewal in appetite resulting from the exposure to a new flavor or food. The phenomenon was first described in 1956 by the French physiologist Jacques Le Magnen. The term has been coined in 1981 by Barbara J. Rolls and Edmund T. Rolls. Its concept illustrates the role of physical stimuli in generating appetite and, more specifically, explains the significance of taste in relation to hunger. Besides conditioned satiety and alimentary alliesthesia, it is one of the three major phenomena of satiation.

This process is most commonly illustrated by a standard buffet. People are more likely to eat a larger amount of food at a buffet because the variety of foods and flavors presented renews a sense of appetite in the individual. A study conducted by Rolls and van Duijvenvoorde in 1984 verified this process by simulating a buffet-style meal. They fed participants four meals that included sausages, bread and butter, chocolate desert, and bananas. They then fed the participants four courses of one of these foods. The results revealed a 44% increase in overall food consumption when exposed to the meals with a variety of foods.

Postingestive feedback factors such as energy density and nutrient composition could affect the palatability of a food which in turn would inhibit or facilitate sensory-specific satiety. Studies done by Birch & Deysher (1986) and B.J. Rolls et al., summarized in a paper by Raynor and Epstein, show that postingesitive feedback does not influence sensory-specific satiety very much. Since postingestive feedback seems to have little effect of sensory-specific satiety, it is probable that sensory-specific satiety is more driven by external factors, such as the sensory properties of the food, than internal factors.

Obesity in relation to sensory-specific satiety
Studies have shown that eating monotonous meals (limited variety in food) results in long-term sensory-specific satiety. By continuing to eat similar meals, a dieter can reduce their overall food intake and use sensory-specific satiety as a tool for weight loss. On the contrary, sensory-specific satiety can also cause obesity because of the stimulation of hunger for foods of different variety. The higher energy content the food has, the less likely sensory-specific satiety will become activated.

Age in relation to sensory-specific satiety
Sensory-specific satiety varies depending on age, with the elderly experiencing decreased sensory-specific satiety and adolescents experiencing more. In a study focusing on age in sensory-specific satiety, it was hypothesized that the degree of sensory-specific satiety is affected by age due to the slow sensory loss that accompanies elderly people. By hypothesis, due to the sensory impairment, a natural, more monotonous diet would occur just due to lack of pleasantness from variety of foods. However, it was proven that sensory impairment did not greatly affect the decline in sensory-specific satiety; instead, there is an unclear cognitive process that relates to decline in sensory-specific satiety that just may be the decreased desire for overall change in the elderly as compared to adolescents.