Researchers believe the brain goes on maturing and is not fully developed until at least the age of 24. Puberty catapults adolescents into a period of risky behaviour powered by their raging hormones, their brains are ill-equipped to exert control and vulnerable to the effects of activities such as drinking and drug taking.
Despite its legal significance, 18 is no longer regarded as the start of adulthood. Fifty years ago, people married and started families at this age. Today these milestones are delayed, over three times more young people are in further education and most spend years in work before marrying and settling down. See full news article here
Other related news articles from same research
– English Daily Mail – Britain among the worst high-income countries for adolescent health behaviour.
– ABC News (USA) – American Teens: Live Fast, Die Hard
Actual research paper can be found here (payment / subscription required)