Large quantities of colorful, "fun-size," Halloween candy are coming soon to homes, schools, and offices near you. How will you resist?

Willpower is important in weight loss and maintenance, but it's also widely misunderstood. Many of us criticize ourselves, often unfairly, for having "zero willpower" or being "terrible at willpower." Yet willpower isn't a personality trait and it isn't really a skill. The science seems clear (though the magnitude of the effect is a topic of debate): willpower is largely a depletable resource, like money in a checking account. And willpower isn't the only "mental task" writing checks from that account.

Here's the fascinating truth about willpower, and how you can use it to maximize your own.

Willpower and icemakers

Willpower has been compared to a muscle, but I liken it to the icemaker in your refrigerator. Suppose you're hosting a dinner party. If you serve all your guests ice water (or cocktails on the rocks), you'll easily go through all the ice in your bin. Give it enough time and the ice-maker will make more, but for the moment, you are simply out of ice. Your refrigerator isn't bad, and it isn't defective; that's just how icemakers work.

But here's where the willpower story gets interesting. As I mentioned above, other "mental tasks" draw from the same "ice supply" as willpower (won'tpower?). Decision-making, concentration, any sustained mental effort – whether or not it relates to eating – all draw from one, solitary ice bin…and as you'll see, the implications of that are significant.

Willpower now means less ice for later mental tasks

Much of what we know about willpower is derived from the work of psychologist Dr. Roy Baumeister, particularly one fascinating experiment that was clever…and sneaky.

Imagine you show up for a research study on "taste preferences" (a white lie). As instructed, you've skipped your last meal and haven't eaten for over three hours. The delicious aroma of "fresh-out-of-the-oven" chocolate-chip cookies welcomes you (no accident) as you walk into the lab.

You sit at a table with warm, moist, chocolate-chip cookies and chocolate candies on one side, and…red radishes on the other. You're required to eat the radishes, but prohibited from eating any chocolatey treats. You're then left to linger for a while….nibbling your bitter radishes in resignation, while gazing longingly at the tempting, but forbidden, cookies before you. Sounds a whole lot like dieting, doesn't it?

It gets worse. You're then taken to another room to "wait for the taste memory to wear off" (white lie), and given a "problem-solving" task. The catch? The task is actually impossible.

And then, the moment of truth. What the researchers really wanted to know all along was this: For how long would the radish folks persist at the impossible task before giving up, as compared to a "chocolate group" who had freely eaten he cookies?

The answer? The radish participants gave up on the problem-solving task more than twice as quickly (or persisted for half as long) as their chocolate counterparts. Why? Because the poor radish folks had used so much "ice" resisting the sweets, they had little remaining for the problem-solving task. They were simply depleted (can you relate?). The chocolate group, on the other hand? Plenty of ice left to spare. The findings were clear: the more willpower you use now, the less ice you have for later. The reverse is also true.

Mental tasks now mean less willpower later

In a previous "Goal Getter" article, I discussed an important experiment in which researchers randomly assigned people to memorize, and then later recall, either a 2-digit or a 7-digit number.

While participants were concentrating on keeping their respective numbers in their heads ("working memory"), the experimenter casually offered a choice of snacks. Guess who chose the most indulgent, sugary snacks? Those with the 7-digit number. Why? Because they were using more of their ice, so they had less leftover for willpower.

The ice-crushing agony of choice

Importantly, decision-making is one mental task that can burn through a lot of ice. We're buried in an avalanche of ever-increasing choices and decisions; a phenomenon psychologist Dr. Barry Schwartz has termed, "the tyranny of choice." Ever buy interior paint? One leading company offers nine types of interior paint, in six different sheens, in over 3,500 different paint colors including 157 different whites (not off-whites, just whites). The more choices available, the more ice-crushing a decision can be.

Simple ways to maximize your willpower

The good news: By limiting the ice you use on other tasks, you'll automatically have more ice for willpower. Here's how:

1.  "Preload" decisions in advance. Apple co-founder Steve Jobs famously ordered 100 identical black mock turtlenecks. That turtleneck with jeans (also one style), became Jobs' daily uniform. The result: he didn't waste precious ice on deciding what to wear to work every day. Packing your lunch ahead of time uses the same principle; pre-decide.

2.  Build habits and routines. The "power of habits" is that they require very little ice. That frees your ice supply for other things like willpower.

3.  Protect your sleep and eat regular, balanced meals. Being tired and "hangry" shrinks your ice bin.

4.  Prepare for ice-crushing days. When you know you have a full day of meetings (or paint selection) ahead of you, anticipate having little ice left by dinnertime. Plan ahead by manipulating your environment (like keeping tempting candy out of sight) and/or preloading the choice (having dinner ready and waiting in the crockpot when you get home).

5.  Choose when to choose. Don't expend precious ice on decisions that aren't important; adopt the philosophy of "good enough." Need more paper towels? Rather than comparing the relative costs and benefits of each option, consider just grabbing the brand you usually buy, and moving on with your life. This way, you preserve your ice for the goals and priorities that matter most to you – which may or may not include white paint.

Stacey C. Cahn, Ph.D. is associate professor of clinical psychology at the Philadelphia College of Osteopathic Medicine (PCOM). Dr. Cahn specializes in obesity, eating disorders, and cognitive-behavioral therapy.


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