Britain's youth is increasingly affected by violent crime, depression, stress and drugs, a survey shows.

The poll of 1,000 16 to 24-year-olds shows they feel they are facing more personal and social problems than they were a year ago.

Key results of the study, conducted by Media Research in June, revealed 20 per cent of males under 24 have been threatened with a knife or weapon and 47 per cent of all participants said this has happened to someone they know; 11% have been asked to join a gang; 15 per cent felt pressured into carrying a weapon and 27 per cent know at least one person their age who carries a weapon; more than 50 per cent feel the UK is less safe than a year ago and 78 per cent do not feel safe walking the streets.

A majority of youngsters also said they feel they have to deal with these worries alone. Almost a quarter, 24 per cent, said they felt they could never talk to their parents about their concerns, 8 per cent have sought help in chat rooms and only 6 per cent have sought professional help.

Almost two thirds said they feel the media misrepresents the issues facing young people.

The study also revealed young people are generally dissatisfied with life. Almost half (41 per cent) said they are unhappy - girls more so than boys; 28 per cent said they "wish they were someone else"; 63 per cent think young people are more depressed now than ever before and 29 per cent think young people in the UK have a tougher time than those in other countries.

Following the survey MTV has launched MTVi, an online service offering support for young people affected by these issues.

Georgia Arnold, senior vice president of social responsibility for MTV networks, said: "While violent crime is clearly a concern to young people, our survey indicates that it is only one factor that leads to increased levels of depression and stress.

"With up to a third feeling that they have to deal with their problems alone, we hope MTVi will become both a useful online resource where our audience can find relevant and useful information on issues that affect them and a portal to expert support beyond the site itself through our partners."

The site will be supported by organisations Big White Hall, Frank, Urban Concepts and the Terrence Higgins Trust which offer advice on anti-violence, drugs, and mental and sexual health.