We Actually Get Nicer With Age

by Elizabeth Bernstein,

Many people become more agreeable, dependable and emotionally stable, and also more introverted.

A few years ago, Brandon Green was sitting on the couch, brooding over a small mistake he’d made at work and the likely consequences. His roommate walked in and began telling him about something funny that happened to him that day. Mr. Green didn’t chuckle or even smile. He scowled and said nothing.

That’s when his roommate offered Mr. Green some valuable analysis: “Never mind,” he said. “You’re just not a happy person.”

“Something happened to me in that moment,” says Mr. Green, a 29-year-old Web analyst from Los Angeles. “I realized I could continue blaming the world, as I had been, or I could try something different.”

Is it possible to significantly alter your personality? Experts say you can.

Several large research studies conducted over the past few years show that a person’s personality naturally changes over the course of adulthood, in response to life events such as entering a committed relationship or advancing in a career.

From the ages of 20 to 65, people report increases in positive traits, such as conscientiousness, and decreases in negative traits, such as neuroticism. Most people tend to become more agreeable, more responsible, more emotionally stable—in other words, their personalities improve. Psychologists call it the Maturity Principle.

Researchers have also long known that friendly, outgoing, responsible people tend to be happier than shy, irresponsible, unsociable people.

When researchers talk about “personality,” they mean a “characteristic pattern of thinking, feeling and behaving that is consistent over time and across situations,” says Christopher Soto, a research psychologist and director of the Colby Personality Lab at Colby College in Waterville, Maine, who was the researcher on the happiness study. Personality is about 50% innate and 50% learned, he says.

According to the Big Five personality model, developed by several sets of researchers starting in the 1940s, the human personality can be divided into five broad categories or domains—openness, conscientiousness, agreeableness, neuroticism and extroversion (also spelled extraversion).

Some personality types are more successful than others, experts say. People who are more conscientious tend to do better in the workplace and school, Dr. Soto says. People who score high on agreeableness and low on neuroticism tend to have more satisfying and stable relationships. Extroverts do better in social and entrepreneurial occupations.

Good news/bad news: Even small changes in a person’s personality can produce important effects on relationships, career, health and happiness.

Think about a bad habit like overeating, Dr. Levak says. To lose weight, you become aware of when and why you overeat. “If you have a tendency to be defensive and want to fight, you tell yourself, ‘OK, when my boss comes to talk to me and I immediately feel I am being judged and want to protect myself, I am overreacting,’ ” Dr. Levak says. “Calm yourself down and don’t argue.”

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