At one point or another, we’ve all laughed at a joke we don’t understand or offered to go halfsies at a restaurant when we wanted the full burger. In short, we’ve people-pleased a bit too far in order to fit in.

Michael Gervais, a performance psychologist who has worked with the Seattle Seahawks, the Red Bull Stratos, Team USA, and Microsoft’s Satya Nadella, says everyone has feared other people’s opinions—or had FOPO.

“Even a hint of potential rejection a couple hundred thousand years ago was a near death sentence,” Gervais, who also serves as the cocreator of the Performance Science Institute at USC and recent author of The First Rule of Mastery, tells Fortune. Our brains are primed to locate danger, such as not fitting in with the crowd, becoming outsiders, and falling behind. However, Gervais says the threat felt in social situations won’t likely kill us, but there is a hefty price to pay when having significant bouts of FOPO.

What is FOPO?

FOPO has three main stages: anticipation, checking, and responding.

“The bulk of the FOPO is this anticipation, this early kind of worry that starts in your closet before going to a holiday party,” Gervais says. We anticipate someone’s negative response or reaction, constantly check for approval and validation in the moment, and respond in ways that instill social acceptance. We may agree to another drink when we don’t want one or stay later at work twiddling our thumbs even after wrapping up.

While it’s important to value other people’s opinions and build strong social networks, the overwhelming fear of fitting in and feeling judged can cause people to act out of anxiety and not intention. We risk missing out on what may serve us.

“We’re checking in to see if they’re accepting us, as opposed to just tuning in to the conversation,” Gervais says. “FOPO is running underneath the surface like an application that quietly runs in the background of a computer. It’s exhausting.”

The brain on fear

In simple terms, excessive FOPO can harm the brain and body. When we begin to fear someone’s opinion, it sends a danger signal to the brain, stimulating the nervous system and causing a stress response. This stress can show up as social anxiety and present in physical ways such as a rapid heart rate. Long-term, constant FOPO can lead to chronic stress, which puts people at risk for chronic conditions.

Of course, stress and FOPO before a job interview or date are expected because healthy bouts of either can alert us that we care. It’s also important to lean on friends and family for support and their opinions when needed. However, when the fear of those opinions runs the show, it can harm us.

The self-health books are right: No matter how hard we try, we cannot control other people’s behavior or opinions. So, it’s time to turn down the volume on the FOPO computer system and feel more at ease.

Here’s how:

1. Awareness is always the start. “Become aware that you’re outsourcing your sense of being okay to the approval or potential rejection of somebody else,” Gervais says. Conforming to receive others’ approval can become second nature. But in interactions at work and home, begin to notice when your words and actions are more geared toward others’ responses than how you feel. When we begin to notice our thoughts, it’s easier to reroute our brain’s patterns and catch ourselves in the act.

2.Go from performance anxiety to a purpose-based identity. When driven by results, like a job promotion, team win, or other accomplishment, we rely heavily on outward validation. Gervais says performance anxiety is the “jet fuel” for FOPO. When we begin to feel driven by curiosity and the chance to learn, we can feel personally motivated to obtain the skills needed to reach a goal or uphold a value without external validation. This mindset shift helps us develop a purpose-based identity instead, Gervais says. And as the popular expression goes, comparison is the thief of joy. “When purpose is really clear, it wins. It can override the brain’s desire to fit in,” Gervais says.

3.Ever heard of the spotlight effect? A group of psychologists coined the phrase in a 1999 research paper. The psychological phenomenon refers to feeling like the spotlight is on you at all times, which can lead to FOPO, social anxiety, and poor well-being. “Most people think that they’re under a spotlight, but in reality, when everybody thinks they’re under a spotlight, you end up not knowing that other people are focusing on themselves and not on you,” Gervais says.

In short, if you’re worried too much about other people’s secondary needs over your primary needs, your well-being can diminish (thank you, Alexis Fernandez’s Do You F*cking Mind? podcast). For many people who feel FOPO more, particularly underrepresented groups who have historically not held positions of power, there can be a fear of regression or letting people down. Gervais hopes we can normalize purpose and innovation while respecting others’ opinions and actions.

“When you’re living life on other people’s terms, you never get to fully live your own,” he says.