Artificial sweeteners might not trick the brain into thinking it is experiencing sugar after all.
A new study suggested people are not driven by their need for a sweet taste, but rather the energy it provides, a Wiley news release reported. According to the trial, the brain experiences more pleasure when faced with real sugar than an artificially sweetened product.
"The consumption of high-calorie beverages is a major contributor to weight gain and obesity, even after the introduction of artificial sweeteners to the market. We believe that the discovery is important because it shows how physiological states may impact on our choices between sugars and sweeteners," Professor Ivan de Araujo, who led the study at Yale University School of Medicine USA, said.
"Specifically, it implies that humans frequently ingesting low-calorie sweet products in a state of hunger or exhaustion may be more likely to 'relapse' and choose high calorie alternatives in the future," he said. "The results suggest that a 'happy medium' could be a solution; combining sweeteners with minimal amounts of sugar so that energy metabolism doesn't drop, while caloric intake is kept to a minimum."
The study was able to pinpoint a "psychological brain signal" that plays into one's choice between artificial or genuine sweeteners. The signal is responsible for regulating dopamine (a chemical that "rewards" the brain) and is only willing to release it when sugar is broken down into usable fuel.
The research team tested the idea on mice by measuring "chemical responses in their brain circuits" and monitoring their behavior in reaction to sugars and artificial sweeteners.
"According to the data, when we apply substances that interfere with a critical step of the 'sugar-to-energy pathway', the interest of the animals in consuming artificial sweetener decreases significantly, along with important reductions in brain dopamine levels," Professor de Araujo said.
"This is verified by the fact that when hungry mice - who thus have low sugar levels - are given a choice between artificial sweeteners and sugars, they are more likely to completely switch their preferences towards sugars even if the artificial sweetener is much sweeter than the sugar solution," he said.
The researchers said the next step is to identify the brain receptors and pathways associated with the phenomenon.
