Child star Malina Weissman poses at the film premiere of "Nine Lives" at the TCL Chinese theatre in Hollywood.

Girls now feel under pressure to look perfect from the age of just seven with a third saying they are made to feel it is the most important thing in life, according to a new poll.

The Girls’ Attitudes Survey, the largest research of its kind, found there has been a steep decline in body confidence over the last five years among girls and young women aged seven to 21.

Only 61 per cent of them said they felt happy with how they look today, down from 73 per cent in a survey conducted in 2011.The annual research by the Guides Association also found 36 per cent of seven to ten-year-olds said people made them think the most important thing about them is how they look.

A quarter of the girls in this age group said they feel they need to be perfect while almost one in six felt embarrassed or ashamed of how they look.

One in three said they felt were not pretty enough while one in three agree women are judged more on their appearance than their ability. Many of those surveyed said that their lives would be improved if girls were not judged by the way they look.

Becky Hewitt, Girlguiding Director, said: ‘This year’s Girls’ Attitudes Survey demonstrates the shocking impact that focusing on girls’ appearance is having on the youngest girls in society.

‘Girls have told us to stop judging them on how they look. Every day in guiding, girls inspire us with their bravery, sense of adventure and their kindness.

‘We are calling on everyone to show girls that they are valued for who they are – not what they look like.’

Liddy Buswell, 18, a girlguiding advocate, said: ‘I’m shocked but not surprised by the survey’s findings. As a Brownie Leader, I’ve experienced these issues first-hand. I’ve witnessed girls unwilling to speak to groups because of how they look, I’ve heard girls saying they’ve been called names at school and [who] aren’t confident trying new activities as a result.

‘No girl should have to worry about the way she looks – she should be having fun and enjoying herself. This year’s survey is a damning indication that something needs to be done to tackle this growing issue.’

The authors of the survey have in previous years highlighted issues including exposure to media and digital images that objectify women, street harassment and sexist online abuse.

Today’s report – from a survey of 1,627 girls and young women – shows ten per cent of seven to ten-year-olds have had people say ‘mean things about their bodies’ most of the time or often.

It comes amid increasing fears that girls are under too much pressure to look good while they are being bombarded with images of the ‘perfect’ body on television and social media.

Throughout October, Girlguiding is launching a campaign to encourage the public to think twice about the way they praise the girls in their lives. Lyra, ten, a South London Brownie, said: ‘I think more girls are judged on their appearance than boys. I don’t think it’s fair that men get treated differently to women. You have to treat everyone the same.’

Pressure to look good has been blamed for a rise in the proportion of teenage girls reporting symptoms of anxiety and depression. A recent government study found one in three young girls now suffer from mental health issues – a rise of 10 per cent in the past decade.

Last year, Dr Aric Sigman, a child health expert, said schools should enlist men to tackle low self-esteem and eating disorders among girls.

He argued that, contrary to popular views, men tended to have a ‘much kinder take’ on female body fat and eating issues than many women.