What Is Optimism Bias And What’s The Harm In It?

Medically reviewed by Laura Angers Maddox, NCC, LPC
Updated May 3, 2024by BetterHelp Editorial Team

Negative things are a fact of life. If you have an optimism bias, you may believe those things are a lot less likely to happen to you than to someone else. Because good things happen, too, if you have optimism bias, you might see yourself as more likely to be on the receiving end of those good things. So, what's wrong with believing in the best for yourself?

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Could you benefit from a more optimistic outlook?

What is optimism bias?

Optimism bias, simply put, is believing that good things are more likely to happen for you and bad things are less likely to happen for you. Optimism bias represents a distinct difference between your expectations for an event and the way the event tends to play out. People naturally have an optimism bias, but some people are prone to have it more often and more intensely. About 80% of all humans have an optimism bias at any given time. Some researchers have even reported that birds and rats have shown optimism bias.

What's curious about optimism bias is that it goes against the way people usually adjust their perceptions of reality. Much of what humans learn comes from trial and error. You may have expectations, but when faced with reality, you learn the truth. This works great with many types of learning, but it doesn't work to teach people to be less optimistic.

Young people tend to feel more invulnerable than older people, so they're more prone to optimism bias. People going through depression typically don't have an optimism bias.

What are the signs of having an optimism bias?

You may have heard optimism bias described in other terms. A person with an optimism bias may have unrealistic optimism or illusions of invulnerability or invincibility.

Here are a few examples of what an optimism bias might look like:

  • Expecting you can speed 20 miles over the speed limit without getting in a car wreck, despite others you know having been in high-speed wrecks
  • Convincing yourself that it will be easier for you to buy a house than it is for others, even if you haven’t saved much money for a down payment
  • Imagining that you'll live to very old age despite knowing that others in your family have died young
  • Believing you can smoke cigarettes without an increased chance of getting lung cancer
  • Buying lottery tickets because you believe you have a better chance of winning than others
  • Spending excessive amounts of money because you expect more money to come in even though you have no evidence that any money is owed to you

What does optimism bias look like in the brain?

Optimism bias is potentially linked to dopamine, a neurotransmitter responsible for boosting our moods. In one study, researchers tried administering dopamine in the form of L-DOPA to see if it affected participants’ level of optimism bias. People were given a list of negative events and asked to rate how likely they were to happen to them. Afterward, they were given statistics on how likely these events were. Finally, they were asked to estimate their probability of experiencing negative events.

Those who were administered L-DOPA tended to retain their optimism. This was true even after they got the statistics showing they were more likely than they'd predicted to experience those negative events. The dopamine seemed to increase their optimism bias by affecting their ability to update what they'd learned.

Since depression usually comes with a decrease in dopamine function, it makes sense that people experiencing depression wouldn't have this advantage in increasing their optimism bias. Thus, they may tend to think pessimistically. People with depression commonly tend to manifest negativity bias.

This failure to code negative information happens in the frontal lobe region of the brain (behind the forehead). The right inferior frontal gyrus reduces its coding of such negative information, which means that the person doesn’t process the message that a negative event is likely.

What are the risks of having an optimism bias?

Having an optimism bias isn't necessarily a bad thing, but it can cause problems for you. For one thing, if you always believe the best is likely to happen and the worst is unlikely, you may behave recklessly and without regard for the safety of others’ well-being.

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People with a strong optimism bias may be more willing to take chances. This can be a positive thing in some situations, but in others, it often leads people to do harmful things. For example, someone who believes they have better odds in a gambling match may lose a significant amount of money, making it difficult to pay for other necessities that they and their families depend on. People with a high level of optimism bias may be financially irresponsible in this way. They may take unnecessary physical risks because they just don't consider the possible consequences.

If you tend to believe the best will happen and the worst never will, you're less likely to prepare for difficulties. This can put you in a dangerous or distressing situation without the means to extract yourself from it.

You may lose money, your home, your possessions, your health, and even your relationships just by failing to acknowledge and address the reality of the situation.

What are the benefits of having an optimism bias?

There are many benefits to the optimism bias. It stands to reason that there would be, after all. With so many people displaying optimism bias, it almost certainly has some survival value.

The ability to explore your world

If you believe nothing bad is going to happen to you, you're more likely to get out and explore your world. This starts in infancy. As soon as a child can move around on their own, they do so without fear, especially if they have a secure attachment to their caregiver. This trend continues through childhood as the child faces new situations, meets new people, and explores different environments. This is not to say that some children aren't anxious, but most children retain enough optimism that they will go out and explore anyway.

Optimism bias carries people through adolescence, adulthood, and even old age. Even though they've heard of bad things happening, they tend to keep getting out and facing the world anyway. Even when they've experienced bad things themselves, they tend to believe that it won't happen again. This means that optimism bias can help you build resilience.

The willingness to seize opportunities

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Could you benefit from a more optimistic outlook?

Sometimes, you don't have a lot of time to consider whether or not to seize the opportunities that come your way. Fortunately, if you have an optimism bias, you're more likely to take advantage of the opportunity while it's still available.

Someone presents a business opportunity, and you're immediately interested and ready to take a chance. You meet someone you like, and you're ready to ask them for a date. You hear about a party that's going on in your neighborhood, and you don't hesitate to join the fun. If it turns out well, you can thank your optimism bias for making it possible.

How can optimism bias impact your health and well-being?

Optimism bias can harm you if you don't take adequate precautions to defend your health. However, it may have positive health effects as well. For example, if you're diagnosed with cancer and have an optimism bias, you might be more likely to believe that treatment will be effective. Thus, you may show up for doctor appointments, take your medication faithfully, and make helpful lifestyle changes. Without that bias, you may be more prone to a defeatist attitude, believing that nothing the doctors or you try will help.

Online therapy for optimism bias

If you feel as if you may be experiencing optimism bias to an unhealthy degree, or if you feel that you do not have an optimistic outlook, then professional mental health counseling might be beneficial for you. Online therapy through services like BetterHelp can help you manage your emotional and mental health when faced with concerns, whether they are minor or major, and can help you keep an optimistic but realistic outlook. This convenient therapeutic method allows you to meet with a licensed professional on a flexible schedule from the comfort of your home.

You also don’t have to compromise on quality of care for the convenience of online therapy. Research has shown that, in a variety of cases, online therapy is just as effective as traditional therapy in offering long-term results with regular treatment. This means you can have access to affordable, high-quality care from anywhere.


Having an optimistic outlook is not a negative thing, but allowing that outlook to blind you to the realities of risk can make life more dangerous. By learning to manage your expectations realistically while still keeping a positive attitude, you can turn optimism bias into a useful frame of reference for everyday concerns. If you're interested in learning more about the benefits and detriments of optimism or wish to start cultivating a more balanced mindset, reach out to an online therapist at BetterHelp.
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