There’s only one cookie left in the box. It looks so forlorn. You know you shouldn’t, you already had several cookies. But it would be stupid to leave a single cookie in the box. You eat the cookie. Sounds familiar? Well, don’t be too harsh with yourself and don’t blame it all on a lack of will power. It might be more than that. It might be that you eat more cookies because cookies just simply taste better for you.
Eat me! Image credit: Bob Smith via Wikimedia Commons
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
How were they able to measure the sensory sensitivity in each women accurately? Did the scientists make sure all of the participants were equally full before the start of the experiment? Did they take in account the body size of each member? What if one of the women didn’t like a certain type of chocolate so ate less? Did they make sure no one was involved in a diet that caused them to restrain themselves from eating to many?
Thanks for many good questions.
They measured sensory sensitivity using the Adult Sensory Profile, a questionnaire comprising 60 items that describe responses to everyday sensory experiences. An individual answers the questionnaire by indicating how often he/she responds to the sensory experiences in the described way, for example “I become dizzy easily” or “I don’t like certain food textures”. Fifteen items of the questionnaire allow to measure sensory sensitivity.
No, the scientists didn’t control if the participants were hungry previous to the experiment. They mention this factor is not perceived as a threat to their finding but that it should be taken into account in replications of the study.
They calculated the participant’s body mass index that ranged from 16.3 to 33.2 but they didn’t check if the relation between sensory sensitivity and food intake was different between participants with different body mass indices.
They didn’t make sure the participants liked the type of chocolate they provided, Galaxy Minstrels. Also, they didn’t take a measure of liking chocolate. However, the ad for the study mentioned that participation involved eating chocolate so presumably all participants liked chocolate.
No, they didn’t consider if participants were on a diet.
Hunger, chocolate liking and diet are variables that could influence the result and that were not taken into account. This study has some limitations and that’s why we should be careful not to conclude from the experiment that sensory sensitivity necessarily explains an increased food intake but it suggests that it might have an influence.
Choosing that last cookie has to do with Humanistic Psychology. Humanistic Psychology emphasizes self determination, free will, and the importance of choice in human behavior. By having the free will to be able to take that last cookie is a good enough answer for some people to do it, because no one is going to tell them they are wrong. So why not take it? On the other hand, people who don’t take that last cookie also deals with Humanistic Psychology because they have good self determination to eat healthier and so no when they know that they really don’t need the cookie.
I found what I just read to be very true. I agree with the idea of tasty foods triggering the brain reward system. I believe that this also is an example of Ivan Polov’s dog and bell experiment. In his experiment, polov would sound a bell just before feeding a dog; After doing this for so long the dog got so used to eating at the sound of the bell, eventually the dog would automatically begin salvating because it expected food at this sound. The same thing goes for humans. Simply Sight or the smell of food sometimes triggers our salvatory glands and makes us feel hungry. After smelling or even just seeing the cookie, your brain could trick you into thinking your hungry; Hence the saying, my eyes are bigger than my stomach.
Humanistic perspective has to do with the importance of choice. While sitting there and staring at the last cookie in the box, you have a choice; to eat it or not to eat it. While you have a choice to make you may or may not want that cookie depending on how your senses like the taste, smell or look of that cookie. The better the cookie smells to you and the better you think it taste the more likely you are to eat that cookie. If you do eat the cookie you are most likely lacking self control over what you can and can’t eat. It works the other way around too, if you don’t eat the cookie you have self control over what you can and can’t eat. Self control and self determination are a big part of the humanistic perspectives.
I always thought i ate the last cookie because i was hungry! I really liked this blog because it gave me an explaination that i would have never thought about until now. Deciding to eat the last cookie is a good example of the single-feature model for decision making strategies. It is a single-feature model because it was a minor choice to take the last cookie instead of leaving it in the box.
I defiantly think the way we eat correlates with the way we feel or the way we want to feel. If you’re feeling down you eat more tasteful foods to comfort yourself (comfort foods) in order to cheer you up and make you feel better. Another way your senses play into the way you feel about food is through smell. Imagine you’re walking through the mall and you’re not hungry suddenly you pass by the food court and smell all the foods and your mouth water and your suddenly hungry just at the smell of food. Odds are you end up getting a bite to eat right there in the mall. All these things are caused just by the way your body feels and reacts to food stimuli.
Nathanael Havel.