Teenage girls are being encouraged to ditch the 'social junk food' of negative role models and follow positive figures like Michelle Obama and Emma Watson, after a groundbreaking study found it dramatically improved their mental health.

The study, Disrupting the Feed, saw girls urged to follow at least four Inspirational 'positive' role models like Serena Williams and Greta Thunberg, to diversify their social media from 'negative' Influencers, such as photoshopped models.

The project was found to dramatically increase the girls' mental health, with 93 per cent of the teenagers saying their outlook had improved over a six month period.

Researcher Dr Terri Apter at Cambridge University told the Sunday Express social media was 'embedded' in the lives of teenagers and called photoshopped models and doctored images 'social junk food.'

The study, Disrupting the Feed, found that the mental health of teenage girls dramatically improved when they followed inspirational role models, such as Emma Watson

Before the study, each girl was interviewed about her interests, values, goals, friends and social media user.

The teenagers followed a wide range of inspirational women, from climate activist Greta Thunberg to actress Emma Watson, as well as role models who are not famous, like survivors of genocide and human trafficking.

By following these figures, the girls' digital footprint was altered and meant they were shown a more diverse feed of people and topics overall.

A second interview was held six months later, after the girls had followed at least four inspirational women.

Michelle Obama was another of the positive role models that the girls said had helped transform their mental health

Almost all of the girls reported that outlooks had changed. One, who believed she could never be an actress as she couldn't afford the training, discovered a scholarship through one of her followed accounts, which she went on to be awarded.

The study, Disrupting the Feed, found that 93 per cent of the girls who took part said their outlook had improved and their horizons had been expanded.

Many of the teenagers said their self esteem had been boosted and others set and achieved higher goals.

The data is set to be presented to media secretary Nicky Morgan, and will go on to be examined at more than 100 schools over the next few months before being rolled out more widely.

The study found that by following a diverse range of inspirational role models, such as Serena Williams, the teenagers could 'transform' their mental health

Leila Symonds, 17, from Kingston Upon Thames, said she only followed Instagram models and reality stars before the study.

She revealed: 'It taught me there are other sides to social media. Instead of hating myself I go to the gym and spend less time on social media.'

Dr Apter, whose research the study was based on, suggested that while social media is embedded in the lives of teenagers, it could be reshaped to show the girls a more 'diverse' landscape.

She called it a 'no brainer' and suggested it be bought out into the education system 'fully'.