It’s an age-old assumption: Success, whether in school, work or relationships, causes happiness. Many of us strive for success, putting long hours into our work or studies in the hopes of achieving success and, as a byproduct of that success, happiness.

But a review of 225 studies in the Psychological Bulletin found that happiness doesn’t necessarily follow success. In fact, it’s just the opposite. Happiness leads to success.

According to the study’s findings, happy people seek out and undertake new goals that reinforce their happiness and other positive emotions.

Sonja Lyubomirsky, Ph.D., of the University of California, Riverside and colleagues reviewed three types of studies: those that compare different groups of people, those that follow individuals over time and those that examine outcomes in controlled settings.

These studies examined questions such as “Are happy people more successful than unhappy people? Does happiness precede success? And does positive affect lead to success-oriented behaviors?”

The results from all three types of studies suggest that happiness leads to greater successes in life. Lyubomirsky suggests “this may be because happy people frequently experience positive moods and these positive moods prompt them to be more likely to work actively toward new goals and build new resources. When people feel happy, they tend to feel confident, optimistic, and energetic and others find them likable and sociable.”

This doesn’t mean that happy people are always successful and never feel sad. Part of a healthy sense of well-being includes experiencing painful emotions in response to difficult and painful life circumstances. These studies found that even generally happy people experienced negative emotions related to challenging or painful life experiences.

Other factors also contribute to success, including intelligence, fitness, social support and expertise. But Lyubomirsky says, “happy individuals are more likely than their less happy peers to have fulfilling marriages and relationships, high incomes, superior work performance, community involvement, robust health and even a long life.”

Strategies for Greater Happiness

So how can you become happier?

In another review of studies on happiness, looking at 51 studies that tested attempts to increase happiness through different types of positive thinking, Lyubomirsky identified some key ways to improve happiness.

Be grateful.

People reported happiness that lasted for weeks and months after writing letters (they don’t even have to be sent) of gratitude to others.

Be optimistic.

Visualizing positive circumstances and outcomes increased happiness for study participants.

Count your blessings.

People who wrote three positive things that had happened to them each week found their spirits lifted.

Use your strengths.

Identifying strengths and making a commitment to try to use them in new ways appeared to enhance happiness in one study’s participants.

Act kindly.

People who help others report that it also helps their own sense of well-being.