Once upon a time, in the spiffing 1950s, characters in children’s books enjoyed wonderful adventures after which they all lived happily ever after. By contrast, reality weighs heavily on today’s young readers, a former children’s laureate has warned.

Anne Fine said that cosy tales in which children’s characters looked forward to future adventures had been replaced by gritty stories that offered no hope for their weary protagonists.Contemporary literature is dauntingly bleak, with depressing endings that do little to inspire.

“In the Fifties, when a strong child was dealing with difficult circumstances, there was always a rescue at the end of the book and it was always a middle-class rescue,” she said.

“The child would win a scholarship to Roedean or something, and go on to do very well. That was felt to be unrealistic and so there was a move away from that. Books for children became much more concerned with realism, or what we see as realism.

“But where is the hope? How do we offer them hope within that? It may be that realism has gone too far in literature for children. I am not sure that we are opening doors for children who read these books, or helping them to develop their aspirations.”

The bestselling writer made her comments at Compelling Novels, Vulnerable Children, an event organised by the umbrella group Children in Scotland for the Edinburgh Book Festival.

She told The Times that she did not wish to see a return to the standards of Enid Blyton, but that she was worried about the effect that gloomy books can have on children. “I can’t see how we roll back from this without returning to the sort of fiction that is no longer credible — books with a Blyton-ish view of things.”

Her concerns were not shared by Anthony Browne, the current Children’s Laureate, who believes that a lot of children’s literature remains upbeat. “There are both types of endings, happier and unhappier. I prefer open endings. I don’t think we are living in an age of depressing, dark endings. If you look at Jacqueline Wilson, she does deal in gritty realism, but her books don’t lack aspiration.”

He recently changed the ending to his forthcoming book — Me and You, a retelling of Goldilocks and the Three Bears in which Goldilocks comes from an impoverished background — so that the ending was less miserable. “My original version had Goldilocks being chased out of the bears’ house and her ending up on bleak, dark streets. I decided to give it a more ambiguous ending, so now she is running toward something that may or may not be her mother.”

Amanda Craig, who reviews children’s books for The Times, said that Fine’s example of an aspirational ending, in which a girl is given a place at a good school, appeared some years ago in Dustbin Baby, an otherwise gritty book by Jacqueline Wilson.

She added that Fine was also capable of producing “utterly bleak” books such as Road of Bones, about a boy growing up in totalitarian Russia. The title of the book, which was shortlisted for a Carnegie Medal in 2007, refers to the bones of political dissidents who dared to oppose Stalin.

Fine was accompanied on the panel at the book festival talk by Melvin Burgess, whose children’s books have dealt with child abuse in a care home and teenage heroin abuse. Burgess argued that young people had a right to know about the seamier side of life. “I think well-informed young people are better able to deal with things they may come across,” he said. “I have had letters talking about the humanity of my books, even when the situations the characters are in are very dark and difficult. Just the fact that they are still making jokes and falling in love. Perhaps the light of hope comes from the reader and not the story.”