A new report by The Prince's Trust says a million young people face a life of poor health and depression unless they get more support to find work.
Prince Charles is calling for more help for the underprivileged young
The Prince of Wales is launching Fit for the Future? at Newcastle United FC's ground, St James' Park.
It found young unemployed people were more vulnerable to experience binge-drinking, depression, poor diet, smoking and drug misuse.
The report also highlights the benefits of building young people's self-esteem.
Based on interviews with more than 1,000 young people aged between 16 and 25, it also says disadvantaged young people are twice as likely to smoke and 50% more likely to take drugs than those from non-deprived communities
The report is to be launched on Wednesday during the prince's visit to a trust project at Newcastle United.
In its introduction the prince said he was "encouraged" that the work of the trust had had a positive effect on young people's lives.
He said: "It is, to me, immensely encouraging to know that young people supported by my trust say that having "a reason to get up in the morning" changes their lives for the better in so many ways - emotionally and physically.
"I happen to believe that if young people are given a purpose in life, they will feel healthier, happier and more satisfied with life overall."
Prince's Trust chief executive Martina Milburn said: "More than one million young people are not in education, work or training.
"By giving young people new skills and a reason to get up in the morning, we can help improve their health and reduce the financial burden on the health service."
Two in five of the unemployed young people who took part in the survey said they were unhappy or depressed.
Half of all young people questioned cited stress, boredom and depression as the main reason for drug misuse or drinking alcohol.
As part of the event, former Newcastle United striker Alan Shearer will talk to unemployed young people on motivation and leading a healthy lifestyle before taking a training session.
The Prince's Trust gives practical and financial support to 14 to 30-year-olds who have struggled at school, been in care, are long-term unemployed or have fallen foul of the law.