Allowing toddlers to watch TV can do more harm than good for their development, an international review has concluded.
Nine in 10 children under the age of two watch television regularly, with some spending as much as 40 per cent of their waking hours in front of the box, it found.
This is despite the fact that there is no scientific research to demonstrate that TV viewing is beneficial for toddlers, the review, published in the Acta Paediatrica journal, concludes.
The review of research, carried out by Professor Dimitri Christakis from the Seattle Children's Research Institute, looked at 78 studies published over the past 25 years to assess the effect of TV on a child's language, cognitive skills and capacity to pay attention.
It found that watching TV programmes or DVD's aimed at infants can delay language development.
A 2008 Thai study, published in Acta Paediatrica found that if children under 12 months watched TV for more than two hours a day they were six times more likely to have delayed language skills.
Another study concluded that children who watched baby DVDs between the ages of seven and 16 months knew fewer words than their peers.
A study conducted by Prof Christakis found that children who watched a lot of TV as toddlers did not perform as well on tests to check reading and memory skills.
Prof Christakis said: "The weight of existing evidence suggests the potential for harm and I believe that parents should exercise due caution in exposing infants to excessive media."
Prof Christakis said he believes TV has a negative effect as it exposes children to flashing lights, and quick scene changes that can over-stimulate developing brains.
"TV also replaces other more important and appropriate activities like playing or interacting with parents," he said.
He said parents needed to be better informed about which activities encouraged development in young children.Reuse content