17 Sensory Specific Satiety: Variety Seeking

Sensory-specific satiety was first described by Rolls et al. in 1981^[1]. They expected that a satiety mechanism existed that was specific to the foods just eaten. In their experiments, they found that the pleasantness of a taste decreased during meals and that when people were instructed to eat until satiation, they stopped eating just before they no longer liked the food anymore; when the food became aversive.

When participants ate the same food again for a second meal, they reported to like its taste less compared to other foods they had not eaten until satiety. Moreover, the decrease in ratings was specific to the food eaten, even if the uneaten foods had similar nutrient composition.

In research following Rolls et al., (1981)^[2] it appeared that especially the sensory characteristics of foods explain this phenomenon. So, this sensory satiety effect is also likely to transfer to products that are of similar taste, smell, and texture. The explanation may be that this mechanism is responsible for long-term health and that this mechanism supports humans to keep a varied diet with a variety of nutrition.

This finding also shows that people will eat more of a varied meal (e.g., a meal with different components or varied buffet) than of a single food.

Then an important question remains: Is this phenomenon simply due to sensory adaptation or habituation?

In short, the answer is no. Eating more in a varied meal is not due to habituation or adaptation. In the studies by Rolls, it appeared that the subjects were still capable of sensing the differences in taste intensity after consuming until satiation, indicating that there was no sensory fatigue after the meal.

Evolutionally, sensory-specific satiety is thought to help humans get all the necessary nutrients via nutrition. In this way, people would not eat the same meal every day out of habituation, but they would switch between different food items^[3].