We don’t eat just because we’re hungry and we need the energy to keep going. We also eat because it gives us pleasure. Food activates what is called the brain reward system. Food is essential to our survival so our body has developed a trick to make sure we eat and live. When we eat, specific brain structures are stimulated, with the consequence that we feel good. We like to feel good, we want to feel good again so we’ll eat again.
Of course some foods are more pleasant to our taste than others. Tasty foods trigger the brain reward system especially well. In lab experiments rats that have free access to normal rat food still choose to expose themselves to extreme cold or electric shocks to get access to shortcake, peanut butter or M&Ms. Also, the tastier the food, the more we eat. How tasty we find a food depends on how it affects our senses; how it tastes, how it smells, its structure to the touch. And the way we perceive the outside world is different from one individual to the next. Some people are more sensory sensitive than others. It’s reasonable to assume then that a sensory sensitive person will have a stronger perception of the pleasantness of food and in turn will tend to consume more tasty foods.
Scientists put this idea to the test. They asked 40 women to fill in a questionnaire that allows to assess sensory sensitivity. At the same time they had access to a bowl full of chocolates. The amount of chocolates the women ate was measured and compared to their sensory sensitivity. High sensitive women did indeed eat more chocolates than low sensitive ones. It seems our senses do influence how much we eat. If sensory sensitivity is high, the reward could be more intense, which would explain a tendency to eat more tasty foods.
Next time, take that last cookie without guilt. Science has just given you a good excuse. You might just be a high sensitive person.
Naish KR, Harris G (2012). Food Intake Is Influenced by Sensory Sensitivity.
PLoS ONE, 7 (8) DOI: 10.1371/journal.pone.0043622