Monell Chemical Senses Center researchers have found that simultaneous cravings for sugar and fat create a formidable challenge for dieting. Their study on the brain’s reward systems uncovered previously unknown brain-gut circuits related to sugar and fat, leading to cravings for unhealthy foods that may go unnoticed.
Sugar and fat cravings create urge to overeat
Researchers propose that the simultaneous cravings for sugar and fat create a strong urge to overeat. This finding reveals the appeal of fats and sugars, offering potential for improved dieting approaches. While the influence of food on decision-making is recognized, the specific brain circuitry involved remains unknown. The vagus nerve transmits information about food’s nutritional value from the gut to the brain, but the molecular basis of the brain’s reward response to food is not fully comprehended.
The study identifies separate neural pathways for fat and sugar cravings in the brain. It emphasizes that when these pathways are activated simultaneously, they strongly stimulate the desire to overeat, affecting the brain’s reward system.
Dr. Guillaume de Lartigue, a lead author from the Monell Chemical Senses Center, notes that even if the overall calorie intake remains constant, the combination of fats and sugars results in a considerable increase in dopamine release, leading to excessive eating.
Researchers have discovered that fats and sugars possess a unique appeal in terms of food reinforcement, with nerve cells in the gut playing a crucial role. Unlike taste cells in the mouth, these gut nerve cells activate distinct gut-brain pathways for fats and sugars, explaining their irresistible nature. The study highlights the impact of subconscious internal desires for a diet rich in fats and sugars on “motivated” eating behavior, potentially hindering efforts to maintain a healthy weight.
In a study with mice, researchers manipulated fat and sugar neurons in the vagus nerve, finding that both trigger dopamine release in the brain’s reward centers. Distinct vagus nerve pathways convey information about fats and sugars, revealing separate neural circuits for each. Stimulating both simultaneously induced strong cravings for high-fat and high-sugar combinations.