the new wave of teenagers who have grown up in the shadow of social media, may be at risk of greater isolation and loneliness File photo: Oupa Mokoena / African News Agency (ANA)

They don’t drink much, few of them smoke, and they are not very interested in television.

They are enthusiastic about sport but shy away from sex, and the women among them can expect to live past the age of 90.

But ‘Generation Sensible’, the new wave of teenagers who have grown up in the shadow of social media, may be at risk of greater isolation and loneliness than their less well-behaved predecessors.

An average 18-year-old spent 27 minutes less a day socialising in 2015 than at the turn of the millennium, the Office for National Statistics (ONS) said.

And the teenage wedding, often in past decades a shotgun wedding, has virtually died out.

Only 683 people were married at the age of 18 across Britain in 2015, the analysis found.

The research, in a paper called Being 18 in 2018, follows growing evidence that teenagers are leading different lives from those in 2000. It said: ‘The biggest changes to how 18-year-olds spend their time may be driven in part by the rise of digital technology.’

There were also fewer drinkers or smokers among the 766,000 18-year-olds living in the UK last year than in the recent past.

In 2005, the paper said, two-thirds of the age group were found to be drinking at least once a week, but by 2017 the share had dropped to 53 %. Girls were likelier to drink than boys – 57 % drank alcohol in the week before they were asked about it, compared to 50 % of boys. Only one in five smoked, down from well over a third in 2000.

Dr Paul Mclaren, of the Priory’s Hayes Grove Hospital, said: ‘What these new trends are showing us is that for Generation Sensible, many of whom prefer their digital devices to a night out, alcohol is not a necessary component of an enjoyable evening.

‘The fact young people are choosing to drink less bodes well for the future – and their parents and grandparents could learn from them.’ As well as socialising less, time spent enjoying films, TV and radio back in 2000 seems to have been replaced by computers and gaming. ‘There was also a rise in the amount of time spent on sport and exercise, up by eight minutes a day,’ the report added. ‘Perhaps another sign of Generation Sensible.’

Girls of 18 can now expect to live until they have reached the age of 90, the report said, and boys can expect to get to nearly 88. While marriage numbers have slipped almost to nothing, the birth rate among 18-year-old women dropped by 58 % between 2000 and 2016, the ONS said.

However, levels of health and good behaviour may come at a price.

This year an ONS survey found that the share of young people aged between 16 to 24, who say they are lonely often or all of the time, is running at three times the rate of loneliness among people above the traditional retirement age of 65.