Mental fatigue fuels cravings and unhealthy choices, new research finds

A recent study led by Marcello Solinas has found a link between mental fatigue and heightened cravings, suggesting that cognitive strain can make people more likely to choose unhealthy rewards.

The research indicates that mental fatigue from challenging tasks may increase the appeal of reward-driven stimuli, impacting impulse control and leading to indulgent choices in areas like food and addiction.

To explore the effects of cognitive exhaustion, researchers examined how both animals and humans respond to rewards after performing mentally strenuous tasks.

In tests, rats that had completed difficult tasks consumed more drugs than those that had rested. In a parallel experiment, people who undertook taxing cognitive tasks reported stronger cravings and ate more potato chips than those who did not experience the same mental load.

Fatigued participants also reported a higher satisfaction rating from the snack, indicating that cognitive exertion not only amplifies cravings but also boosts the pleasure derived from indulgent choices.

In a follow-up study, participants rated the taste appeal of chocolate higher after completing challenging cognitive tasks, while other non-food items, such as a pen or a sticky note, didn’t receive the same increase in appeal. This suggests that mental fatigue specifically enhances the allure of rewarding items rather than affecting general judgment.

These findings may have implications for managing addictions and other impulse-driven behaviors.

The research team noted that the brain's response to mental fatigue might serve as a coping mechanism, providing pleasure or relief during cognitive strain. Understanding this connection between mental fatigue and heightened cravings could pave the way for new strategies to help people manage impulsive behaviors by addressing the effects of mental exertion on their choices.