The sweetness of control When humans and other animals travel the road to excess, whether for food consumption, violence, power, or sex, it is either because they gave in to an in-the-moment impulsive itch or because a history of losing self-control turned into an addictive habit. What causes us to lose our sense of moderation, allow our mental brakes to slip, and give in to temptation? What causes our preferences to inconsistently and irrationally shift over time, allowing seductive offerings to win? If you are the eminent social psychologist Roy Baumeister who has contributed fundamental insights into the nature of evil, the answer is simple: sugar. Love it. Want it. Need it. When we work hard, focusing on a difficult problem or trying to figure out the best decision, exhaustion strikes. Part of our exhaustion comes from the fact that we have depleted a critical resource: sugar, or more precisely, glucose. When the availability of this resource diminishes, we also lose self- control. This is why the loss of self-control has a cycle that follows the time of day, with the greatest losses occurring late rather than early: diet breakers are more likely to pig out in the evening than early in the morning; shoppers are more likely to buy impulsively as the day moves on; impulsive crimes and relapses of addiction are evening affairs; judges are more likely to dole out punishment at the end of a day in court than when they start a new day. Dozens of experiments show that if you have to exert self- control in one context it taxes your capacity to exert self-control in another. For example, if you ask subjects to avoid laughing while watching a comedy routine, avoid thinking about a white bear, or avoid eating chocolates now to have radishes later, these same subjects will squeeze a hand grip for a shorter period of time than subjects who never contended with the various self-control tasks. When you deplete your personal resources, you lose your grip, opening yourself up