Study: How fat and sugar cooperate with the brain to destroy the diet
What a gut punch.
Experiencing cravings for fat and sugar simultaneously is what makes dieting so difficult, researchers from the Monell Chemical Senses Center in Philadelphia reported in a study published Thursday in the journal Cell Metabolism.
Researchers found that the way fat and sugar affect the brain, via different pathways from the gut, leads to the unconscious desire to overeat, SWNS reported.
“It’s a punchline to the brain’s reward system,” lead study author Dr. Guillaume de Lartigue said in a statement.
He added: “Even if the total calories consumed in sugar and fat remain the same, the combination of fats and sugars leads to a significant increase in dopamine release and, ultimately, overeating.”
Dopamine is a neurotransmitter that is made in the brain and is known as the “feel good” hormone.
Humans are hardwired to seek out behaviors that release dopamine, including overeating, according to the Cleveland Clinic.
Until now, it has remained a mystery why fat and sugar are such an attractive combination, as in donuts, but these new findings reveal that fat and sugar have their own specific pathways of the vagus nerve, according to SWNS.
The vagus nerve, which runs from the brainstem to the abdomen, is responsible for functions such as digestion, according to the Cleveland Clinic.
“Food is nature’s ultimate enhancer, but why fats and sugars are particularly attractive has been a mystery,” De Lartigue said, adding: “We have now identified that neurons in the gut rather than taste cells in the mouth are the main driver.”
In this study, the researchers stimulated the vagus nerves in mice with light, and found that this forced the mice to search for food that would engage those specific circuits.
The study authors determined that neurons in the vagus nerve sense sugar and fat, which share parallel, but distinct, reward circuits.
Activation of the fat and sugar circuits stimulated the mice to overeat. Scientists said this may explain why humans unconsciously seek to eat foods high in sugar and fat alongside each other.
“The connection between our gut and our brain occurs below the level of consciousness,” De Lartigue said. “We may want to eat these types of foods without even realizing it.”
The researchers hope that their findings will make treating obesity easier in the future.
“Understanding the wiring diagram of our innate drives to consume fats and sugars is the first step toward rewiring them,” De Lartigue explained. “This research opens up exciting possibilities for personalized interventions that can help people make healthier choices, even when they are faced with tempting foods.”