Dieters often blame low blood sugar or deprivation and lack of pleasure (no dessert?!) as the source of their cranky attitudes. However, recent research indicates that there is another reason for all that irritability: the exercise of self-control.
The most common school of thought holds that self-control is a “finite resource”. Every time you select salad over steak, you chip away at that block of self-control. As you deplete your reserves, you are less likely to be able to control feelings of anger and aggression (and acting on them) at inappropriate moments.
Researchers David Gal (at Northwestern University) and Wendy Liu (at UC San Diego) subjected study participants to various tests of self-control. Those who made the “smart” choice (in the study, an apple instead of a chocolate bar) were much more likely to opt for a movie with an aggressive theme. In another study, those who chose between an apple and chocolate before reading a health message suggesting exercising were far more likely to rate the message as irritating.
So, what is your best way around this dilemma? How do you ditch the ‘tude without dumping your diet? Try to avoid situations that force you to exercise your self-control. If you are choosing between and apple and an orange, you are going to be a lot less likely to experience feelings of anger and aggression than if you chose between an apple and a chocolate bar. When diet choices become habit, and less choice is involved, you are much less likely to feel deprived. If what you really want is a chocolate fix, no apple is going to get you past it. Every now and then, go ahead and reach for that candy bar.