SUNDAY, Feb. 12 (HealthDay News) -- A best friend can help children deal with negative experiences, a new study suggests.

"Having a best friend present during an unpleasant event has an immediate impact on a child's body and mind," said study co-author William Bukowski, a psychology professor and director of the Center for Research in Human Development at Concordia University, in Montreal. "If a child is alone when he or she gets in trouble with a teacher or has an argument with a classmate, we see a measurable increase in cortisol levels and decrease in feelings of self-worth."

In conducting the study, researchers asked 55 boys and 48 girls from grades 5 and 6 in Montreal to record their feelings and experiences in a journal over the course of four days. The children's levels of cortisol -- the stress hormone -- were also monitored in regular saliva tests.

The study, recently published in the journal Developmental Psychology, found that cortisol increased and self-worth decreased when a child had a negative experience. However, with a best friend present when trouble struck, cortisol levels and feelings of self-worth changed less.

The researchers noted that what happens during childhood can affect people as adults, including having feelings of low self-worth.

"Our physiological and psychological reactions to negative experiences as children impact us later in life," explained Bukowski in a university news release. "Excessive secretion of cortisol can lead to significant physiological changes, including immune suppression and decreased bone formation. Increased stress can really slow down a child's development."

The study's authors said previous studies have also shown that having friendships can help protect people from bullying, exclusion and other forms of aggression.

More information

The University of Arizona provides more information on peer relationships and friendship.

-- Mary Elizabeth Dallas

SOURCE: Concordia University, Montreal, news release, January 2012

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