Remember when you tried to convince your parents your ‘dinner stomach’ was full, but you still had room for sweets on account of your ‘dessert stomach’? Turns out, science can actually back up this idea.
One door for the main meal and another for dessert. That was just a fact when I was growing up, or at least in my eyes, it was. A ‘dessert stomach’ was always how I made sense of never being too full for ice-cream or cake, or whatever sweet goodness I knew existed somewhere in the fridge or freezer. Heck, it is still how I make sense of it now.
Because let’s be honest, it doesn’t matter how full we are, even post-Christmas lunch when stomachs are bulging, and you groan in food euphoria, the majority of us can never say no to whichever festive dessert is on the menu.
Why? It turns out that I was kind of, sort of, right, because it comes back to this notion of the separate ‘dessert door.’ Yes, dessert stomach, dessert door – however you refer to it -is a real thing. And it is backed by science. You’re welcome.
This notion of always finding room for dessert has been studied (as all good things are) and proven to be fact, all because of something called ‘sensory-specific satiety’.
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Dr Barbara Rolls, Director, Laboratory for the Study of Human Ingestive Behaviour and Penn State University Professor, has been studying sensory-specific satiety since 1980.
“The decline in pleasure you derive from food is specific to the food you have been eating, or other foods that are similar,” she says.
“So, while you might lose your appetite for that food, a different food will still be appealing. That’s why you always have room for dessert.”
In other words, what you viewed as the feeling of being full, may not necessarily have been the sensation of your body being physically full, rather your brain’s loss of interest in the food or meal you were eating, telling you “I’ve just had enough of that food, I want something else.”
It can be based on the taste, appearance, smell, and texture, or a combination of these in the food you are eating, as the more of it you eat, the more the pleasantness of the food reduces. And, once that interest has been lost your brain, will send messages saying, “no more.” Well, until a big bowl of Ben & Jerry’s Chocolate Fudge Brownie ice cream comes your way, and you find that room for dessert.
The theory has been tested with experiments by Oxford University which showed cells in brain reward centres, which produce feelings of pleasure, respond less to a food the more it is eaten.
This experiment was also carried out by news website Vox, based on Professor Rolls’ past studies.
Within the Vox study, a group of volunteers was given a main meal of macaroni and cheese, followed by dessert of macaroni and cheese. They were asked how much interest they had in the meal and the amount they ate was also recorded.
Their interest plummeted from 6.2 out of ten, to 1.3 after their first course. On average, they managed just one ounce of pasta for ‘dessert’, and by the time they had finished this, their interest in macaroni cheese was 0.2 out of ten.
The experiment was then repeated on a different day where the volunteers were given ice cream for dessert, rather than more pasta. Their interest in ice cream remained high throughout the meal of macaroni and they ate three times more of the ice-cream than they’d eaten of the pasta ‘dessert’.
“Sensory-specific satiety is that change in how much you like a food, how much of a food you want to eat while you are eating it,” says Dr Rolls. And the reason humans experience this, is for a reason, to keep us healthy.
“We’re omnivores, and we need to eat a variety, it helps guarantee you will eat the variety of nutrients you need,” Rolls explains.
Although sensory-specific satiety is our body’s way of ensuring a balanced diet, Dr Rolls also says it can backfire if we are presented with too many options like at a buffet, or Christmas lunch, where there is a higher likelihood of us overeating. Because with more variety comes more interest.
“Change in appeal during a meal keeps us going, keeps us eating,” she says.
In a 1984 study by Dr Rolls, she conducted an experiment where participants were given a four-course meal. One group was given four courses of the same food, the other were given four very different dishes.
The second group consumed 60 percent more calories than the first because they were kept interested in the food, proving how much variety and pleasure in what we are eating can impact how much we consume.
But because 2020 has given us so little that is positive, I say let’s focus on the fact there is a scientific explanation for always finding room for dessert. Oh and bring on the Ben & Jerry’s!