If you’re making impulsive decisions you normally wouldn’t, you could be in need of a few more hours of sleep. Grabbed a donut at the morning meeting when you normally wouldn’t touch it? Splurged on that expensive top you’ve been eyeing online? A lack of sleep may be to blame. “The prefrontal cortex is greatly affected by sleep deprivation,” explains Harris. “This area is associated with judgment, impulse control, visual association and attention. Less sleep leads to poorer judgment and acting impulsively, e.g. poor eating when sleep deprived, buying things without thinking about the consequences, irritability and mood issues with others.”

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