Ego Depletion

Ego depletion is an idea that we have a limited supply of mental energy for self-control tasks. You can think of it as a “fuel tank” for willpower that can be drained with use. Using willpower wear out your mental stamina, making it harder to exert self-control later on - if you use up your willpower on one challenge, you have less available for the next one. In other words, willpower is a limited resource, similar to a muscle that gets tired after heavy use.

The term “ego depletion” was coined by social psychologist Roy Baumeister, whose 1998 experiment illustrated the concept¹. In that study, one group of people had to resist eating freshly baked cookies and eat plain radishes instead. Later, when everyone tried to solve a difficult puzzle, the radish-eaters gave up much sooner than the people who got to eat the cookies. The act of resisting temptation (not eating the cookies) drained their willpower, so they had less mental energy left for the puzzle.

This¹ and follow-up studies² led to the “strength model” of self-control, which says self-control works like a strength or fuel that can be temporarily used up. After exercising a lot of self-control, your mind gets fatigued (depleted) for a while, and you become more likely to lose focus, give in to impulses, or quit tasks more easily.

Ego depletion isn’t just a lab theory - it’s something you might notice in daily situations where your willpower runs low. Here are some relatable examples of how ego depletion can show up in everyday life:

Making numerous decisions, especially complex or high-stakes ones, imposes a significant cognitive load and is thought to draw down the same limited resource needed for other forms of self-control. When in a state of decision fatigue, you’re more likely to make impulsive choices, opting for immediate gratification over long-term rewards.

One famous example of decision fatigue involves judicial rulings. Studies of parole board decisions found that judges were significantly more likely to grant parole at the beginning of the day or immediately after a food break. As the time since their last break increased, the percentage of favorable rulings steadily dropped, sometimes approaching zero just before a break³.

Regulating your emotions also uses up self-control. Let’s say you’ve been staying patient and calm during a day full of frustrations - dealing with rude customers, sitting in traffic, or handling stressful tasks without complaining. By the end of the day, you might find yourself snapping at a loved one or losing your temper over something minor. This happens because suppressing anger or other strong emotions consumes mental resources, hastening ego depletion. After controlling your feelings for hours, you have less capacity left to continue keeping your cool⁴.

Beyond personal mood, ego depletion can also degrade the quality of social interactions by impairing prosocial behaviors⁵. Acts of kindness, empathy, and altruism often require overriding selfish impulses and engaging in effortful reflection and perspective-taking. When ego-depleted we are less likely to engage in such types of behaviors⁶. This suggests that being a good friend, partner, or citizen is not just a matter of character but also depends on having sufficient mental energy to overcome self-interest and engage with the needs of others.

We tend to give up on difficult or frustrating tasks more quickly when our self-regulatory resources are low. This can effectively sabotage any goal that requires consistent, daily effort, like adhering to a diet, maintaining an exercise regimen, quitting smoking, or completing a major project⁷.

When you spent all day concentrating on projects, making decisions, and rushing to appointments, by evening you just want to collapse on the couch and do nothing. That drained feeling is ego depletion in action. Your mental energy for focus and discipline has been used up, so it’s harder to stay productive or attentive as the day wears on.

Sticking to a diet is a great example as well. Imagine you manage to eat a healthy breakfast and lunch, and even resist the cookies or chips at the office snack table. By nighttime, however, your resolve weakens and you “cheat” on your diet with fast food or late-night snacks. Because you spent so much mental energy saying no to cravings throughout the day, you experience ego depletion by dinner time and give in to temptation.

The most effective approach to self-regulation is to intelligently manage multiple interconnected systems that affects your mental energy. This involves proactively shaping your day and internal state to make self-control less costly and more sustainable.

Self-regulation begins with the body as brain is a biological organ that requires proper maintenance.

• Take care of proper nutrition and hydration.
• Prioritize 7-8 hours of quality sleep per night to ensure your prefrontal cortex has the resources it needs for impulse control and focus.
• Exercise regularly to improve your mood and cognitive function, contributing to a greater capacity for self-control.

The most effective form of self-control is to not need it in the first place. This involves structuring your environment to reduce the number of temptations and difficult decisions one must face.

• Keep junk food out of the house to make healthy eating the default.
• Lay out gym clothes the night before to reduce the friction of starting a morning workout.
• Use apps to block distracting websites during work hours.

You can read more about environment design in the Choice Architecture note.

Mental stamina fluctuates throughout the day. By paying attention to your natural energy rhythms you can schedule the most cognitively demanding tasks for periods of peak mental energy and less demanding tasks for natural energy lulls. This strategic scheduling maximizes productivity and reduces the feeling of fighting against oneself.

Continuous mental effort leads to fatigue. Take deliberate, strategic breaks to allow recovery of your mental energy. You can use methods like the Pomodoro Technique where you work in focused 25-minute intervals with short breaks in between.

Breaks should ideally involve shifting your mental state, for example by getting up to stretch, walking outside for fresh air, or listening to music. Positive emotions have been shown to help replenish self-regulatory capacity, so a short, enjoyable activity can be particularly restorative.

As research has shown, beliefs about willpower also have a powerful effect on performance⁸. A simple act of seeing challenges as opportunities instead seeing them as willpower drainers can drastically reduce their impact on your mental energy.

When faced with a difficult task or a setback, replace the negative thought (e.g. “I’m not good at this”) with the growth-oriented one (e.g. “I haven’t mastered this yet”). Simply believing that effort can be energizing and that self-control is a skill that can be developed can help buffer against feelings of depletion.

Effort feels less costly when it is aligned with your deeply held values and goals. By making the goal itself more rewarding you can reduce the amount of mental energy you need to work towards it. This involves connecting daily tasks to a larger sense of purpose and setting clear, specific, and meaningful goals. When your motivation is high (particularly intrinsic motivation), you are more likely to push through fatigue and persist.

You can read more about values and goals in the following notes: Personal Values Clarification, Personal Mission Statement, Personal KPIs, North Star Metric.

Self-regulation requires self-awareness. Practices like mindfulness and meditation help you become more attuned to your internal states (thoughts, feelings, and impulses) without judgment. This awareness allows for proactive rather than reactive energy management. By noticing feelings of stress or fatigue as they arise, you can choose a thoughtful response (e.g., taking a break, practicing deep breathing) instead of reacting impulsively. This builds the capacity to pause between stimulus and response, which is the very essence of self-control.