New Year’s resolutions: Are you suffering from decision and willpower fatigue?

This week’s edition of Psych Wednesdays was written by Sarah Roberts, Ph.D. candidate in Psychology at the University of Quebec in Montreal and blogger at Psychobabble for Normal People. It was originally published on Psych Your Mind on January 25, 2013.

Why is it that at the beginning of January, we’re able to keep our New Year’s Resolutions—hitting the gym regularly, drinking less alcohol, wasting fewer hours on Facebook, following a budget or a diet—but our willpower wears off as the month wears on? Similarly, how come at 9am, 10am, and 1pm, we easily walk by a tantalizing plate of brownies someone left in the lunchroom at work—but at 4pm, we give in and eat six?
Psychology researchers who study willpower have discovered the phenomenon of ego depletion, a condition of low mental energy that can lead to poor self-control and poor choices. Rather than thinking through decisions and making smart choices, the ego-depleted brain resorts to one of two strategies: a) recklessly obeying impulses, or b) avoiding decisions by sticking to the status quo.

It’s not hard to see that ego depletion isn’t helpful when it comes to keeping our New Year’s resolutions–but what causes it?

Ego depletion can be caused by decision fatigue and willpower fatigueDecision fatigue can happen in any situation that requires numerous or repeated decisions. For example, imagine sitting down with a wedding planner to plan the menu for your big day. You’ve got a budget in mind and you’re determined to stick to it. In the beginning, you and your partner eagerly discuss each hors d’oeuvre, happily debating the merits of sushi versus sashimi and prosciutto-wrapped melon versus bacon-wrapped shrimp; but after a long day during which you choose from hundreds of options, you reach a state of ego depletion via decision fatigue. So when the wedding planner starts talking cake, you forget about your budget and impulsively choose the insanely expensive cupcake tower the planner suggests—even though it puts you way over budget. And when you get home that night and have to decide what to make for dinner, you’re liable to chuck your New Year’s resolution to eat less fast food and default to your I-don’t-feel-like-cooking standard of ordering pizza.

Willpower fatigue occurs when we have to exert repeated or prolonged self-control. For example, say you resolved to cut back on drinking and you’re attending a wedding with an open bar and non-stop refills: you’re able to turn down champagne the first few times it’s offered, but by midnight, you’re in a state of ego depletion from exerting prolonged will power, and you end up grabbing and chugging the next three glasses that are offered. Ego depletion via willpower fatigue explains why, after months of resisting your gorgeous, flirtatious, and available colleague, one night you give in and cheat on your partner. And it explains why we successfully avoid the lunchroom brownies in the morning, but end up bingeing in the late afternoon. (Ego depletion via low blood sugar may also be a factor in the latter case).

Ego depletion via decision fatigue and willpower fatigue can help explain why we tend to slide on our New Year’s Resolutions partway through January, or to lapse in our self-control at the end of a long day. The good news is that resolution-thwarting ego depletion can be avoided and self-control and good decision-making preserved.

To prevent decision fatigue, avoid making too many decisions at once, and organize your day so that some of your decisions are pre-made. For example, bring your lunch so you don’t have to decide whether or not to order a salad or a burger. If you have an important decision-making meeting at work in the morning, don’t schedule a meeting with the wedding planner the same afternoon.

To prevent willpower fatigue, avoid situations that require prolonged willpower. If you don’t want to drink at the wedding, tell the waiters you don’t drink so they won’t keep offering to fill your glass. If you have a writing deadline, turn off your wireless access for a few hours so you don’t have to keep resisting the urge to procrastinate on Facebook. If you want to eat less, don’t go to all-you-can-eat buffets.

Another way to avoid ego depletion via willpower fatigue or decision fatigue is to have a strict and clear rule. Whereas willpower and decisions are invoked in the moment, rules are created in advance and based on a rationale. So say you’ve resolved to cut back on drinking in general, but you’re out with friends after work on Thursday. The second you’re faced with a glass of wine, willpower pits the force of your desire to drink against the force of your determination to resist, creating discomfort. In contrast to a vague resolution to drink less, say you have a firm rule to drink alcohol only on weekends. Your rule eliminates the need for willpower because alcohol on a Thursday is not even an option. For another example, say your rule is that you work out every Monday, Wednesday, and Friday before work. If this is your established and inflexible rule, you don’t have to use willpower to get out of bed when your alarm rings, nor do you waste your decision-making reserves; the decision is pre-made so you just hop out of bed.

Ego depletion is the enemy of New Year’s Resolutions, but smart planning and clear rules can help us avoid it. By conserving willpower, making decisions in advance, or creating a rule, we increase our ability to get to the gym, ignore Facebook, and stick to a budget or a diet.

Let us know if this works for you!


Danziger, S., Levav, J., & Avnaim-Pesso, L. (2011). Extraneous factors in judicial decisions Proceedings of the National Academy of Sciences, 108(17), 6889-6892 DOI: 10.1073/pnas.1018033108

Hofmann, W., Vohs, K. D., & Baumeister, R. F. (2012). What people desire, feel conflicted about, and try to resist in everyday life.Psychological Science, 23, 582-588.