The top global cause of illness and disability for adolescents was declared to be depression, with suicide ranking as the third-biggest cause of death, the World Health Organization said on Wednesday.
After directly consulting with 10 to 19-year-olds around the world to assess the health issues that affect them, the findings were pulled together in a wealth of published evidence and was reported by the UN agency, Agence France-Presse reported.
"The world has not paid enough attention to the health of adolescents," said Flavia Bustreo, head of the WHO's family, women and children's health division.
Some studies show that half of all people who develop mental disorders have their first symptoms by the age of 14, said the report.
"If adolescents with mental health problems get the care they need, this can prevent deaths and avoid suffering throughout life," it said.
The study looked at a broad range of issues, including tobacco, alcohol and drug use, HIV, injuries, mental health, nutrition, sexual and reproductive health, and violence, according to AFP.
Traffic injuries was named as the second leading cause of illness and disability, with boys three times more likely to die than girls.
By increasing access to reliable and safe public transport, improving road safety regulations such as alcohol and speed limits, establishing safe pedestrian areas around schools and graduating licensing schemes where drivers' privileges are phased in over time, countries would be able to reduce the crucial risk of death, WHO said.
Worldwide, an estimated 1.3 million adolescents died in 2012, it said. The top three causes of death globally were road traffic injuries, HIV/AIDS, and suicide.
"We must not let up on efforts to promote and safeguard the sexual and reproductive health of adolescents, including HIV," said WHO scientist Jane Ferguson, lead author of the report.
The second-biggest killer after suicide was complications during childbirth for adolescent girls.
