Peer pressure is the feeling of being pushed by friends or classmates to think, look or act a certain way. In adolescence people spend more waking hours with peers than at any other stage of life. This is a period of social reorientation. Young people spend less time with their parents and more time with same-age peers. It is natural for people to compare themselves to their peers as they think about who they want to be or what they want to achieve.

Teens may be more open to peer pressure partly because they worry more about what others think of them. Unlike younger children, they can imagine at an abstract level how others see them. Many young people struggle to understand how their peers see them, and they worry about being rejected if they do not fit in. Social worker Emma Petree says peer pressure gets really intense around the start of middle school.

Some of it starts before any push. Much of the similarity between friends was there before they became friends. Peers with similar interests and habits tend to gravitate toward each other. A clique differs from a group of friends. In a clique, leaders decide who is in or out. Members of a friend group are free to hang out with others.

In 1951 psychologist Solomon Asch set up a simple test. People judged which of three lines matched a target line, and the answer was always obvious. Asch's volunteers heard other people give a wrong answer. These helpers, called confederates, gave the wrong answer on 12 of the 18 trials, which were called the critical trials. On average about one third, or 32%, of the people on the critical trials went along with the group's clearly wrong answer.

When people are unsure what to do in a social situation, they naturally look to others for cues about what is acceptable. Pressure can spread through a group. The people most easily influenced follow first. Then others go along, thinking "everyone else is doing it, so they must know what they're doing." Extension specialists point out that most peers are typically not making unhealthy choices, so "everyone is doing it" is often not true.

Responding to peer pressure is part of human nature, but some people are more likely to give in and others are better able to resist and stand their ground. People who are low on confidence, or who tend to follow rather than lead, could be more likely to seek their peers' approval by giving in to a risky challenge. Some experts say "peer influence" is a better term, since it is not always about doing something against your will.

Peer pressure can be a positive force. Students at high schools where many classmates go on to college are more likely to go themselves. Peer influence can push teens to become more assertive, try new activities or get more involved with school. Prosocial behavior means actions meant to benefit others, such as volunteering, donating and sharing. Research shows adolescents also copy the prosocial behavior of their peers.

Saying no can feel like it has a high social cost. So having a friend or two who feel the same and will stand beside you can take some of the social pressure off. Often it takes just one person to speak out or do something different to change a situation, and friends may follow. Researchers say peers and parents can both support young people's positive adjustment. Peers more often reinforce family values than work against them.

Nancy Hill is a Harvard psychologist. She says kids will always want to fit in with peers, so the useful question is what they are fitting into and whether it helps them or derails them. Hill suggests practicing scenarios where a feeling might be tested. She suggests helping a young person think through a response that feels natural to them. Experts say it helps to explain values, and not only say "don't do this," so young people can make decisions for themselves and feel independent.

A young person is more likely to ask a trusted adult for help if they know they will not get into trouble for asking, so adults are advised to praise the choice to ask. A secret code word with a parent is a way to ask for help and leave a spot without being embarrassed in front of friends. A parent or other adult can step in when peer pressure gets too hard for a kid to handle. A grown-up you trust can help.

Words to know

• adolescence: the teen years
• clique: a closed group
• confederates: secret helpers
• gravitate: drift toward
• abstract: in the mind