Sweet drinks such as sugary tea help to reduce stress at work, and make people less likely to be aggressive or argumentative, psychologists claim.
The energy boost provided by the sugar enables the brain to maintain control over its impulses, meaning people can prevent themselves from reacting spontaneously when under stress, researchers said.
Tests on a group of volunteers, some of whom were given lemonade sweetened with sugar and some with artificial sweetener, showed that those who had drunk sugar performed better under pressure.
Each subject was asked to carry out several stressful tasks before giving a presentation, some of which researchers criticised in order to provoke them.
People who had drunk the sugary lemonade were less likely to snap than those who had not, the Journal of Experimental Social Psychology reported.
The Australian psychologists said: "When provocation is likely, for example, when encountering a difficult supervisor at a work meeting, drinking a sweetened beverage prior to this encounter might increase one’s ability to effectively inhibit aggressive impulses.
"Consuming a sweetened beverage on the commute home following a stressful day could reduce aggression toward family members or fellow drivers."
Glucose is required by the brain to enable "executive functioning", which included the ability to restrain one's impulses, the researchers from the University of New South Wales and Queensland University said.
They said: "Despite the widespread notion that glucose consumption can lead to a “sugar high” resulting in impulsive behaviour our data suggest that glucose can increase executive control when provoked."