Friendship serves as a buffer against stress
By Liz Lockhart
Friendship is a great source of comfort, happiness and support throughout one’s life and now, we are told 
by a new study, it is also a buffer against the negative effects of stress.
Friendship is particularly helpful in middle childhood as this is a time when rejection from peers can cause stress.
This study was conducted in the Netherlands by researchers from Radbound University Nijmegen and is published in the journal Child Development.
The human stress hormone, Cortisol, is used in the body to mobilise energy and enables us to respond to potential threat when we are stressed. An increase in the levels of cortisol helps us to adapt the way in which we function when circumstances change and assists us when we are faced with stressors.
Although Cortisol is useful in stressful situations there is a downside. Chronically high levels can have negative effects on the way in which we function. This can impact on our immune system.
In this study, nearly 100 fourth grade children were observed to determine whether exclusion by peers and victimisation were related to an increase in cortisol and whether friendships could moderate this association. The age group of children, the study says, has been understudied in this regard to date.
The child participants were part of a longitudinal study that was conducted in the Netherlands and designed to be representative of the Dutch population.
The children were asked by the researchers to nominate classmates who were often picked on, bullied or excluded by other children. They were also asked about the number of friends they had in their class and the quality of their best friendships. The researchers also questioned the parents of the children about behavioural problems which they were experiencing with their children. They then measured the children’s cortisol levels by collecting saliva. This was done five times a day on two consecutive school days.
The study found that elevated levels of cortisol were found in children who were excluded by their classmates. This elevated level became smaller over the course of the day. The study suggests that both of these findings may show that exclusion is stressful.
This effect was even more pronounced in children who were both excluded and had few friends or had friendships which were low in quality.
Surprisingly, victimisation by classmates was not associated with increased levels of cortisol which suggests that bullying is not as stressful as exclusion.
‘Together, the results demonstrate that although friends cannot completely eliminate the stress of exclusion at school, they do reduce it. And the number and quality of children's friendships can serve as a buffer against being rejected,’ said Marianne Riksen-Walraven, professor of developmental psychology at Radboud University Nijmegen.
