The TV parenting guru said Facebook, Twitter, SnapChat, WhatsApp et al were fuelling 'narcissistic' behaviour in teenagers.
She said a generation of young people were growing up unable to communicate with their parents, while inhabiting a materialistic online world full of 'half-truths' and body image paranoia.
The supernanny was speaking about her latest TV series, Jo Frost Family Matters, in which 60 families were filmed in their homes.
She told At Home magazine that 'the overriding theme seems to be a lack of confidence and trust within families in Great Britain'.
Jo said: "I have dealt with lots of teens in my show and the big problems teenagers are facing is the impact of social media in all forms, as it seems like it has a heavy negative influence on them.
"Social media sites feed narcissistic behaviour and the need to be popular and they are being bombarded with half-truths and some facts.
"It creates addictive natures as teens become dependent on their phones, which has the effect of breaking strong communication and relationships with friends and family.
"The rising numbers of violent video games, and the lack of empathy that it creates, leads to antisocial behaviour and bullying is more visual than it has ever been in our lifetime."
She called for an 'open dialogue' between parents and children to encourage young people to seek other sources of media and teach them not to feel negative about body image.
She also said peer pressure to take drugs and alcohol was another 'big problem', while job opportunities were 'scarce' for many young people. This was all compounded by their parents' money worries.
Jo said: "For lots of families, the recession brought about a grim reality.
"Many suffered work-related hardships from unemployment, to pay cuts, part-time work, women having to take shorter maternity leaves, parents working longer hours and even losing their homes in extreme cases.
"These bleak circumstances can leave some families feeling very helpless and stressed, angry, desperate, and the emotional strain can have a huge impact on the way that parents react to their children.
"I do think it's important, though, that parents help their children understand that money worries are their problem and not a burden on the children's shoulders.
"Although I do advocate making children aware that the family are prioritising expenses and therefore there might be some things they cannot have immediately."