So, you’re trying to get someone (or many someones) to change their usual behaviour. You’d like them to start composting or stop smoking or participate in peace talks or pick up their clothes. You give them all the help and advantages possible, and sure enough, they start to change. Since this is going so well, you encourage them to make another change, or go a little further.
And the improvement comes to the kind of unpleasant halt usually associated with a skateboard hitting quicksand.
Making and maintaining a behaviour change requires self-control, or at least self-supervision. We can’t operate on automatic pilot when we have to remember to do (or not do) that new thing. And what isn’t widely known is that self-control can be exhausted.
Dozens of studies have shown this in different ways. Study participants who obediently ate radishes even though freshly baked cookies were nearby (and no one was looking) gave up trying to solve a frustrating puzzle more than twice as soon as participants who had been told to eat cookies or hadn’t seen food at all. In another study, participants who did mathematical problems while trying to “not think about a white bear” were less able to suppress their amusement during a funny movie later.
Another study showed that making decisions – including purchasing decisions – uses up as much self-control as resisting temptation. Self-control is depleted even further if there are many decisions or if they are unpleasant. (This may partially account for consumers’ tendency to buy less often when offered too many choices.)
Other activities that drain our reservoir of self-control include trying to control our thoughts or emotions, forcing ourselves to do a boring task, managing the impression we’re making on other people, coping with fears and helping others. The harder it is, the more it temporarily drains our ability to do other difficult tasks (which may help to explain moral self-licensing).
A few techniques have been discovered to help:
- One study found that self-control lowers our body’s levels of glucose (sugar) and that drinking a sugary beverage after a difficult task revives self-control more quickly.
- Another found that affirming important personal values also revived self-control after a draining activity.
- And, of course, turning a behaviour into a habit removes much of the self-control drain associated with it. (If only it were that easy.)
The message for those of us trying to change the world is to avoid asking people to use too much self-control at once. When your friend has just started recycling, don’t push her to forgo plastic packaging. When your colleague has just given a difficult presentation, don’t suggest celebrating with a new exercise routine.
And for the sake of your health and sanity, don’t ask someone who’s just planned a wedding to do anything difficult. They’ll claim it was justifiable homicide.