Children who complain of headaches, stomach aches and sickness may actually be victims of bullying.
New research suggests that parents should keep a look out for such symptoms as they may be important warning signs that a child is being tormented.
It says that bullying often goes undetected because many children are reluctant to talk about it.
The most common psychosomatic symptoms bullied children experience include stomach aches, dizziness, breathing difficulties, nausea and back pain. The researchers, from the University of Padua, in Italy, studied 30 research papers which included information on almost 220,000 children from 14 countries, Health Dayreports.
They discovered that children who are being bullied are more than twice as likely to develop unexplained physical symptoms as those who are not bullied.
"The results of this study suggest that any recurrent and unexplained physical symptom can be a warning sign of bullying," study author Gianluca Gini from the University of Padua told Health Day.
Marlene Snyder from Clemson University in South Carolina, U.S., explained that a psychosomatic symptom can often be spotted as it will clear up as soon as the child has been told they do not have to go to school.
She suggests that parents look out for subtle signs of bullying, such as a child being afraid of text messages arriving or suggestions that they are sitting alone at lunchtime.