Your diet is not working? Guilt can be your brain
The feeling of pleasure afforded by that bite into a sweet and caloric value of food activate different brain pathways. Therefore, the brain acts as a diet enemy and when having to choose between eating something unpleasant taste, but caloric, and more tasty food, but no calories, some vertebrates are the first choice, giving priority to have power to ensure ” survival “than taste something more tasty and light.
The finding is from a study by researchers at Yale University in the United States, in collaboration with colleagues from the Institute of Biomedical Sciences, University of São Paulo (ICB-USP) and the Centre for Mathematics, Computing and Cognition at the Federal University of ABC (CMCC-UFABC).
Through a series of experiments on mice, researchers found that the feeling of pleasure of the intake and calorie and nutritional value of the food evoke neuronal circuits of the striatum, an area of the subcortical system within the brain. The active region is the same, but awakened circuits are different.
“We note that there are different neuronal circuits in the same region of the brain involved in the perception of sensation of pleasure afforded by eating sweet food that are different, for example, those that encode the calories of these foods,” said Tatiana Lima Ferreira, the CMCC researcher -UFABC.
While the neural circuitry of the ventral part of the striatum are responsible for the perception of sensation of pleasure afforded by the sweet taste, the dorsal part of the neurons are responsible for recognizing the caloric and nutritional value of sweetened foods.
In order to identify which neuronal circuitry of the striatum are involved in specific perception of the nutritional value and the gustatory food, the researchers conducted an experiment to quantify the release of dopamine in the brains of mice after being exposed to sweet substances with and without calories.
For this, the animals licked the tip of a water fountain with sweetener and received doses of solutions containing sugar or sweetener also non-caloric, injected directly into the stomach.
The results of the experiment indicated that there was an increased release of dopamine in the ventral striatum of the sweetener during consumption regardless of which solution was being administered in the digestive system of animals – it was sugar or sweetener.
“The neural circuits that region of the brain do not discriminate if the food being ingested or has no calories. Just the food is tasty for dopamine is activated,” said Tatiana.
In contrast, there was an increased release of dopamine in the dorsal striatum region only when the sweetener intake was accompanied by intragastric infusion sugar – which suggests that the neuronal circuits of the brain region that are sensitive to calorie food.
The researchers also evaluated the effect of decreased sensation of pleasure provided by the ingestion of an unpalatable substance, but caloric, in the release of dopamine in these regions of the brain of mice.
For this, they changed the taste of the sweetener that animals lick the trough of the nozzle to add a bit of denatonium benzoate, a compound that imparts a bitter taste to the formulations. At the same time, the mice received intragastric infusions of sugar.
Although the amendment of the sweetener flavor discontinued the dopamine release in the ventral striatum induced sugar injected into the stomach of the animals, there was an increase in the neurotransmitter release in the dorsal striatum, the researchers found.
“This suggests that the brain is craving for calories, not the sweet taste of food, which would control our ‘need’ and, in some cases, cravings for sweet substances,” he said.