A huge number of adults in the United Kingdom have experienced suicidal thoughts because of concerns about their body image, according to a new survey.

In a poll of 4,505 adults aged 18 and over by the Mental Health Foundation, it found just more than one-third of UK adults have felt anxious or depressed because of concerns about their body image, and one in eight adults have experienced suicidal thoughts or feelings because of concerns about their body image.

The survey was commissioned as part of Mental Health Awareness Week in the UK, which this year has the theme of body image.

The charity is calling for changes in the way social media and advertising portray body image, with just more than one in five of all UK adults and almost half of 18 to 24-year-olds having said social media had caused them to worry about their body image.

Mark Rowland, chief executive of the Mental Health Foundation, said: "Our survey indicates that millions of adults in the UK are struggling with concerns about their body image. For some people this is potentially very severe, with large numbers saying they have self-harmed or had suicidal thoughts and feelings."

Women are more likely to be affected by body image issues than men. One in ten women said they have self-harmed or "deliberately hurt themselves" because of their body image, compared to four percent of men.

The charity said men are also affected, with a quarter having admitted they felt depressed because of concerns about their body image.

"Women, and particularly young women, are showing the highest rates of distress. Significant numbers have felt feelings of disgust and shame or changed their behavior to avoid situations that make them reflect negatively about their bodies," Rowland said.

"But body image issues can affect anyone and at any stage in life. Our research suggests that a worrying proportion of men have felt anxious or depressed about their bodies."

Rowland said that with many people attributing their concerns about body image to social media, the government needs to do more to tackle the issue.

It's not just adults who are feeling compelled to look a certain way or portray a particular image on social media.

Almost two-thirds of young people feel pressure to look their best online, according to new findings from the Be Real Campaign. The research showed that more than 67 percent regularly worry about the way they look and the same number edit photos of themselves before posting on social media.

More than half of the 2,000 young people surveyed aged 11 to 24-years-old, said that celebrities and influencers sharing more realistic images of themselves would encourage people to post content that more accurately reflect what they look like in real life.

"Social media continues to present a multitude of dangers for young people which they have been left to navigate on their own devices. These dangers are not just limited to the content they see, but also the pressure young people face to emulate them," said Denise Hatton, chief executive for YMCA England & Wales.

"Young people and the general population need to be conscious about the content they are posting online. In order to support this, we're calling on people across the nation to sign our Body Image Pledge and to be confident of how they look."

The YMCA's Be Real Campaign is urging people to fight against unrealistic beauty standards and hold brands and organizations accountable if they lack diversity or promote an unhealthy body image.

"YMCA's Be Real Campaign is encouraging young people to curate their own safe spaces online and follow accounts that make them feel good about themselves," Hatton said.

In a latest study, Britain was found to be lagging behind other European cities when it comes to providing the number of hospital beds for young people struggling with mental health issues.

According to a study into all 28 countries in the European Union, the UK is in 18th place for the number of inpatient beds available per 100,000 young people.

That's despite the UK having the largest number of services dedicated to child and adolescent mental health.

There are 9.4 beds per 100,000 young people in the UK, while Germany had the most with 64 beds and Sweden had the least with 1.2 beds.

Swaran Singh, a professor at the University of Warwick and project coordinator for the Milestone Project, said the small number of beds in the UK doesn't reflect the whole situation and have to factor in other services such as community care.

Singh said, "With around a tenth of young people likely to experience mental health issues, it's a matter of concern that the approach to child mental health varies so dramatically across Europe. Our youth deserve better mental healthcare than they currently receive."

Singh also called for more community-based care and psychiatrists if improvements are to be made to help young people with mental health issues.

The Milestone Project's aim is to understand and improve transition of care from children and adolescent mental health service?to adult mental health service for young people across different healthcare systems in Europe.