Teenagers should be given weightloss jabs after research found that they can halve obesity rates, scientists have said.

Obese adolescents aged 12 to 18 were given the drug semaglutide on a weekly basis for 16 months in a US trial, along with lifestyle counselling.

The study of 134 teenagers found the drug reduced weight to a level below that of obesity in nearly 50 per cent of cases.

Researchers said the result was “historically unprecedented”, achieving results previously only seen with surgery.

They said the jabs should be made available on the NHS for all obese teenagers – saying it was “the earlier the better” when it came to starting such treatment.

The scientists also said that those given the weekly jabs might need to stay on them for life to avoid putting the weight back on.

At the end of the 16 months, 45 per cent of participants experienced a reduction in BMI below the clinical cut-off point for obesity, along with 12 per cent of participants in the placebo arm. Both groups received lifestyle counselling. 

The average weight dropped over the trial period was from 17 stone to 14 stone.