People who like intensely sweet tastes may make certain decisions differently from people who prefer less sweetness, according to new research that challenges a common assumption about impulsive behavior.
In two laboratory experiments involving 149 young adults, researchers found that people who preferred the sweetest sucrose solution were more likely to choose smaller rewards they were sure to receive. They were also more likely, in some situations, to choose a smaller reward available immediately instead of waiting for a larger one.
At first, that could look like greater impulsivity. But the researchers found that these choices seemed to be tied more closely to a preference for certainty.
The findings, published in Frontiers in Psychology, do not show that liking sweets makes someone impulsive, nor did the researchers study sugar cravings or how much sugar participants usually ate. Instead, the study looked at whether preference for very sweet tastes was associated with the way people handled risk and delayed rewards.
Researchers at HSE University first tested how much sweetness participants preferred using a standardized taste test. Those who preferred the most concentrated sucrose solution were classified as “sweet likers.”
Participants then completed several decision-making tasks. Some required them to choose between a smaller guaranteed reward and a larger reward that was less certain. Others asked them to choose between a smaller reward available sooner and a larger reward available later.
Sweet likers were more likely to favor the guaranteed option. They were also more likely to choose an immediate reward when the alternative required waiting.
But when both choices required a delay, sweet likers were actually more willing to wait for the larger reward.
That difference mattered. Once researchers accounted for participants’ tendency to avoid uncertain outcomes, the connection between sweet preference and impulsive choice became much weaker.
“We are used to thinking of impulsivity as an inability to delay gratification. However, our findings point to a different mechanism: choosing a smaller immediate reward may stem from a desire to avoid uncertainty rather than from a desire to receive a reward as quickly as possible. This changes our understanding of the nature of impulsive behaviour,” said lead author Anna Davidovich, a research assistant at the Centre for Cognition & Decision Making at the HSE Institute for Cognitive Neuroscience.
The researchers’ explanation is straightforward: Waiting introduces uncertainty. Something could happen before a delayed reward is received. A person who strongly prefers certainty may therefore choose the immediate option even if waiting itself is not the problem.
The researchers also suggested that the brain’s opioid system could potentially play a role because it is involved in both reward processing and responses to threat and uncertainty.
However, the study did not measure opioid activity, brain activity or other biological mechanisms. That explanation remains a hypothesis rather than a finding of the study.
The research also has important limits. Participants were young adults completing laboratory decision-making tasks, so the results may not reflect how people behave with food, money or other choices in everyday life. Sweet preference was measured using sucrose solutions rather than participants’ usual diets or real-world eating habits.
For now, the findings suggest that a preference for very sweet tastes may overlap with how some people respond to uncertainty. They do not show that a sweet tooth is a sign of impulsiveness or a particular personality type.
The research was supported through the Basic Research Program at the National Research University Higher School of Economics, or HSE University.