Have you ever noticed that people on diets are really crabby? While many might blame it on low blood sugar or lack of pleasure (rice cakes, cabbage soup, canned tuna — BORING!), recent psychological research suggests that it's actually the exercise of self-control that leads people to become irritable and aggressive at inappropriate times.
The prevailing theory is that because self-control is a finite resource, when you deplete it — say by consistently choosing celery over chocolate or by refraining from splurging at a party — you're less likely to be able to control urges toward anger or aggression when they arise at inappropriate times.
"Research has shown that exerting self-control makes people more likely to behave aggressively toward others, and people on diets are known to be irritable and quick to anger," said researchers David Gal, an assistant professor of marketing at the Kellogg School of Management at Northwestern University.
"Given that most individuals are frequently engaged in self-regulation throughout any given day — whether it be resisting the urge to talk back to one's boss, to eat an extra helping of mashed potatoes, to save instead of spend, or to work out on the treadmill instead of going out for cocktails with co-workers — our ﬁndings suggest that anger-related behavior might be more prevalent than previously assumed or reported," Gal wrote. They also described some interesting marketing implications suggesting, for example, that anger-themed video games (like the mobile video game "Angry Birds") would do well to advertise in health-food aisles of grocery stores, at gyms, and other places where people try to exert self-control.
As for the angry and self-deprived dieter, Gal's best advice involves "avoiding self-control dilemmas in the first place or cognitively reappraising the situation so that the virtuous choice does not involve a denial of satisfaction." This is where a positive attitude will carry you far. Remember how empowered you feel after a nutrient-rich snack, and how satisfied you feel after a challenging Arc workout. And if the situation warrants it, go ahead and splurge once in a while.