Marcella La Cioppa New research has revealed that there is an unconscious link between the gut and the brain, and it is precisely because of this that we feel the uncontrollable craving for sugary or high-fat foods.
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The longstanding mystery of why we overeat unhealthy foods remains a complex issue. Despite being aware of the powerful influence food has on our choices, the exact brain circuits behind this mechanism have been unclear.
The vagus nerve carries sensory information from the gut to the brain about the nutritional value of food. However, the molecular basis of the brain’s reward system related to what we eat has not been fully understood.
The study
A new study published in Cell Metabolism has revealed the internal neural wiring, uncovering separate pathways for the craving of fats and sugars, as well as a concerning result: the combination of these pathways excessively triggers our desire to eat more than usual.
Researchers have pinpointed that nerve cells in the gut, rather than taste cells in the mouth, are a key factor. They discovered that fats and sugars activate distinct pathways between the gut and the brain, explaining why that doughnut can be so irresistible.
The team utilized cutting-edge technology to directly manipulate fat or sugar neurons in the vagus nerve system and demonstrated that both types of neurons cause a release of dopamine in the brain’s reward center. They identified two dedicated pathways in the vagus nerve: one for fats and another for sugars. These circuits, originating in the gut, transmit information about what we have consumed to the brain, laying the groundwork for appetite.
This finding sheds light on why dieting can be so challenging. The human brain may be subtly programmed to seek out combinations of high fat and sugar content, regardless of our efforts. Communication between our gut and brain occurs below the level of consciousness, meaning we might crave these types of food without even realizing it.
The team anticipates that this line of research could offer hope for developing anti-obesity strategies and treatments. Targeting and regulating the gut-brain reward circuits may provide a new approach to curbing unhealthy eating habits.
Source: Cell Metabolism
