Gargling with a sugary liquid might give you that extra bit of willpower to say no to that second cookie or resist the urge to smoke. A new study published Oct. 22 in Psychological Science showed that swishing around a mouth rinse containing glucose (i.e., sugar) improves self-control, according to ScienceDaily.
Researchers asked 51 students to perform a task known to deplete self-control and afterward were given the Stroop test — that mind-bending phenomenon whereby we see the word “green” in red font or the word “blue” in black font and we just can’t seem to accurately name the font color. Try it: Purple Brown Red Green (You should have said “red, blue, green, purple.”)
During the Stroop test, half of the students gargled with sugar-sweetened lemonade, while the other half gargled with Splenda-sweetened lemonade. Those who rinsed with the lemonade containing real sugar — rather than the artificial sweetener Splenda — responded significantly faster.
"Researchers used to think you had to drink the glucose and get it into your body to give you the energy to (have) self control," said co-author and University of Georgia psychology professor Leonard Martin. "After this trial, it seems that glucose stimulates the simple carbohydrate sensors on the tongue. This, in turn, signals the motivational centers of the brain where our self-related goals are represented. These signals tell your body to pay attention."
The study authors believe the glucose could be associated with emotive enhancement, helping us focus on goals and provide a nondominant response — e.g., saying “red” instead of “purple” in our Stroop test example.