When it comes to mental health, what's going on with young people - particularly, teenage girls?There's been a lot of coverage in the media recently regarding mental health difficulties facing boys, not least around the struggle to get to grips with 'modern masculinity'; undoubtedly, it's a tough time to be a young man. But looking at figures for mental health problems in children and teens, there's clearly something going on with girls too. For some years now, research has shown that more girls are experiencing problems than boys, with a troubling spike in difficulties showing up in the late teens. In some years, twice as many girls as boys have what the research calls “probable mental health disorders” - with rates of eating disorders charting four times higher and rates of self-harm up to seven times higher in girls than in boys. All sorts of factors can affect those figures, from whether people are prepared to discuss how they feel, to how those feelings are labelled. But these don’t explain why statistics over recent years continue to show a disparity between boys and girls. On today's programme, Claudia explores the issue with help from a variety of guests, visiting King's College London's (KCL) Institute of Psychiatry, Psychology and Neuroscience to speak to Gemma Knowles, a lecturer in epidemiology and youth mental health; Craig Morgan, professor of social epidemiology and head of the Health Service and Population Research Department; and Valeria Mondelli, a clinical professor of psychoneuroimmunology - about their work with young people in the UK and beyond, trying to uncover the deeper causes and to find new solutions.She also hears from some of the young people involved in a major study into mental health, conducted by the team at KCL and spanning nearly a decade.Claudia is joined by Dr Linda Blair, a clinical psychologist, who brings her own professional experience to bear discussing the trends and challenges of youth mental health. Organisations offering information and support relating to mental health can be found at BBC Action Line: bbc.co.uk/actionlinePresenter: Claudia Hammond Producer: Lucy Taylor Studio Manager: Emma Harth Production Coordinator: Siobhan Maguire Editor: Holly Squire