Studies in both animals and humans have suggested that consuming artificial sweeteners can make you feel hungry and actually eat more. A comprehensive new study co-led by the University of Sydney has revealed for the first time why this response occurs. Published in the journal Cell Metabolism, the results shed light on the effects of artificial sweeteners on the brain in regulating appetite and in altering taste perceptions. Researchers from the University of Sydney’s Charles Perkins Centre and the Garvan Institute of Medical Research have identified a new system in the brain that senses and integrates the sweetness and energy content of food. “After chronic exposure to a diet that contained the artificial sweetener sucralose, we saw that animals began eating a lot more,” said lead researcher Associate Professor Greg Neely from the University of Sydney’s Faculty of Science.
In the study, fruit flies that were exposed to a diet laced with artificial sweetener for prolonged periods (more than five days) were found to consume 30 percent more calories when they were then given naturally sweetened food. “When we investigated why animals were eating more even though they had enough calories, we found that chronic consumption of this artificial sweetener actually increases the sweet intensity of real nutritive sugar, and this then increases the animal’s overall motivation to eat more food,” said Associate Professor Neely.
This is the first study to identify how artificial sweeteners can stimulate appetite, with researchers identifying a complex neuronal network that responds to artificially sweetened food by telling the animal it hasn’t eaten enough energy. “Using this response to artificially sweetened diets, we were able to functionally map a new neuronal network that balances food’s palatability with energy content. The pathway we discovered is part of a conserved starvation response that actually makes nutritious food taste better when you are starving,” said Associate Professor Neely.
Source: Science Daily