You asked
I would like to know about the prevalence of young adults mental health i.e. whether things like suicidal ideation, self-harm, depression and anxiety have increased.
We said
We do not collect information on suicidal ideation or self-harm, nor do we collect data on clinically diagnosed cases of anxiety or depression.
We do collect information on the population’s self-reported anxiety using the following question; “On a scale where nought is ‘not at all anxious’ and 10 is ‘completely anxious’, overall, how anxious did you feel yesterday?”.
This information is self-reported and estimates of means are published, alongside proportions of the population rating their anxiety within four categories (0-1, Very Low; 2-3, Low; 4-5, Medium; 6-10, High).
This information is available for the UK as a whole, and by 5 year age bands (from those aged over 16 to those aged 90 and over). The data are from the Annual Population Survey (APS), with the most recent period available where the estimates are broken down by age being the year ending December 2016.
As part of the Measuring National Well-being programme, we report on the "Percentage of those in the UK with some evidence indicating depression or anxiety". This is measured through the General Health Questionnaire (GHQ-12) and is collected on Understanding Society, the UK Household Longitudinal Study. GHQ-12 asks respondents 12 questions about their recent feelings. These questions are then scored and added together with the total score ranging from a minimum of 0 and a maximum of 12. A score of four or more indicates that the individual may have symptoms of mild to moderate illness such as anxiety or depression. This information is provided as percentage of respondents who have a score of 4 or more at the UK level. The most recent time period available is for 2014 - 2015.
Understanding Society, the UK Household Longitudinal Study is not carried out by us, but the data are available from the UK Data Service under varying licensing agreements.
Information relating to anxiety and depression is also available from Public Health England.