Grateful teens are more likely than their less grateful peers to be happy, less likely to abuse drugs and alcohol and less likely to have behavior problems at school, according to research presented at the American Psychological Association's 120th Annual Convention.

"Gratitude played an important role in many areas of positive mental health of the teens in our study," said lead author Giacomo Bono, PhD, psychology professor at California State University. "Increases in gratitude over a four-year period were significantly related to improvements in life satisfaction, happiness, positive attitudes and hope."

To measure the development of gratefulness, researchers asked 700 students ages 10 to 14 to complete questionnaires in their classroom at the beginning of the study and four years later to provide comparison data.

When comparing the results of the least grateful 20 percent of the students with the most grateful 20 percent, they found that teens with the most gratitude by the end of the four-year period had:

• gained 15 percent more of a sense of meaning in their life;

• become 15 percent more satisfied with their life overall (at home, at school, with their neighborhood, with their friends and with themselves);

• become 17 percent more happy and more hopeful about their lives;

• experienced a 13 percent drop in negative emotions and a 15 percent drop in depressive symptoms.

Even if teens didn't start off with lots of gratitude, they could still benefit if they developed more gratitude over the four-year period, according to Bono. "They experienced many of the same improvements in well-being. Moreover, they showed slight reductions overall in delinquency, such as alcohol and drug use, cheating on exams, skipping school, detention and administrative discipline," he said. "For instance, the top 10 percent of those who developed the most gratitude showed 9 percent less delinquency than the bottom 10 percent in gratitude growth."

For the purposes of the study, the authors defined grateful teens as having a disposition and moods that enabled them to respond positively to the good people and things in their lives, Bono said. The four-year study took place in New York with a sample that was 54 percent girls, 67 percent white, 11 percent Asian-American, 10 percent African-American, 1.4 percent Hispanic, 9 percent other and 1.6 percent no response.

"These findings suggest that gratitude may be strongly linked with life-skills such as cooperation, purpose, creativity and persistence and, as such, gratitude is vital resource that parents, teachers and others who work with young people should help youth build up as they grow up," Bono said. "More gratitude may be precisely what our society needs to raise a generation that is ready to make a difference in the world."