There's been an increase in the number of young people seeking help for anxiety.
39% of users of Jigsaw, the National Centre for Youth Mental Health, said they experienced the condition.
Traditional factors include parental separation, traumatic experiences, peer pressure and exam stress.
However, the service says they're seeing new issues particular to life in 2018, including identity uncertainty and high expectations of themselves and by parents and society.
"There is a deepening sense of uncertainty amongst many young people we support in relation to their sense of identity and place in this fast-paced, evolving world," said Dr Gillian O’Brien, Director of Clinical Governance at Jigsaw.
"High expectations of self are one key driver of anxiety which can be compounded by the expectations of parents, teachers and society at large.
"However, if there is something positive that can be extracted from this rise in levels of anxiety it’s that young people today are so much more literate in terms of their mental health and wellbeing than they have ever been before.
"The very real challenge for us in Jigsaw, alongside other mental health services, is to ensure that help is available."
According to Jigsaw’s Annual Report 2017, other common mental health difficulties included: low mood (31%), stress (25%), sleep changes/issues (17%), anger (15%), family problems (14.5%), isolation/withdrawal (14%), self-criticism (12%), low self-esteem (12%) and thoughts of self-harm (11%).
Relationship difficulties, family breakdown, bullying, exam stress, isolation and peer pressure were all seen as common contributory factors.