The next step in research is to "understand which signals are telling the brain's reward system that something has changed metabolically," he said. "When we ingest calories, we are changing our metabolism."
Anthony Sclafani, a researcher at the Brooklyn College of the City University of New York, said the findings are important, because they're the "first to show that nutrients in the gut can directly activate the brain reward system."
The results still need to be confirmed, said Sclafani, a professor of psychology who studies how the body interacts with food.
He added that the findings could lead to better understanding of artificial sweeteners, which are "are sweet in the mouth but, unlike sugars, do not act in the gut to reinforce food preferences."
However, "even if sugars and artificial sweeteners in the mouth and gut activate brain-reward systems in humans, the implications for human feeding behavior and disorders are not certain at this time," he said. "What is certain is that more research is needed to know the impact on human feeding behavior and to exploit this new knowledge in the clinical treatment of obesity and eating disorders."
Learn more about healthy eating from the National Institutes of Health.
SOURCES: Ivan E. de Araujo, D.Phil., assistant fellow, The John B. Pierce Laboratory, Yale University, New Haven, Conn.; Anthony Sclafani, Ph.D., distinguished professor, Department of Psychology, Brooklyn College of City University of New York; March 27, 2008, Neuron
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