A new study has found that teens are taking longer to grow up than they were 20 years ago.

The study led by Dr Jean Twenge, professor of psychology at San Diego State University, found that Generation Z is delaying a range of the classic milestones of adulthood – including drinking, driving, having sex, dating and working.

Published in the journal ‘Child Development,’ the study analysed survey responses from 8.3 million teenagers between 1976 and 2016.

It found that the 18-year-olds of today are acting like the 15-year-olds of the 1990s – with the popularity of social media and smart phone apps leading them to stay at home and avoid drugs and alcohol.

It found that:

• 66% of 17/18-year-olds surveyed in 2014 had tried alcohol, compared to 81% in 1994
• 73% had driving licences, compared to 85% in 1994
• 58% were dating, down from 83% in 1994
• 56% had worked for payment, down from 72% in 1994

Dr Twenge warned against classing the trends as either good or bad, noting that while teenagers may be less prepared for adulthood, they are safer than before – with the rate of car accidents, binge drinking, teen pregnancy and teen crime falling dramatically in the US.

Writing in The Atlantic Magazine, she said this new generation of teenagers, born between 1995 and 2012, grew up with smart phones and social media – adding that they do not remember a time before the internet.

“The arrival of the smart phone has radically changed every aspect of teenagers’ lives, from the nature of their social interactions to their mental health,” she wrote.

“These changes have affected young people in every corner of the nation and in every type of household.”

Positive and negative signs

She noted that some of these generational changes are positive, some are negative and many are both.

“More comfortable in their bedrooms than in a car or at a party, today’s teens are physically safer than teens have ever been,” she said.

“They’re markedly less likely to get into a car accident and - having less of a taste for alcohol than their predecessors - are less susceptible to drinking’s attendant ills.

She warned however that they are now more vulnerable than Millenials were – with rates of teen depression and suicide on the rise since 2011.

“It’s not an exaggeration to describe [Generation Z] as being on the brink of the worst mental-health crisis in decades. Much of this deterioration can be traced to their phones,” she wrote.

Dr Twenge also noted that delayed adulthood trends should not be solely attributed to technology.

She said that increased life-span, and falling birth-rates are also driving the change – adding that when parents have fewer children and expect them to live full lives, they tend to expend more care on them.