Concerns about body image are making large numbers of people depressed and even suicidal, a survey suggests.
The poll of 4,500 UK adults found a third had felt anxious about their bodies, with one in eight experiencing suicidal thoughts.
The Mental Health Foundation, which commissioned the survey, said the issue could affect anyone at any age.
The charity wants advertising and social media firms to take more care with the way bodies are portrayed.
The issue of body image is one of the main theme's of this year's Mental Health Awareness week.
The charity is promoting a number of personal stories as part of its push to raise awareness about the issue.
They include one from Justyn Bravescar, 25, from Croydon, south London.
He is a film-maker, blogger and mental health advocate, and has adopted Bravescar as his surname.
As a toddler he accidentally poured a pan of boiling water over his body, resulting in severe burns all over the upper half of his body, including his neck.
He was always very self-conscious about this and thought he would never find love or be at peace with himself.
When he was older he started looking into reconstructive surgery, but says he had an epiphany when a skin camouflage tattoo artist told him that his scars were beautiful.
"As my scars were covered much of the time, it was very much an internal battle for me" said Justyn.
"I worried about my scarring and what people would think. It has only been in the last few years that I have really accepted them. They are part of me."
He now has tattoos that highlight and celebrate his scarring.
High rates of distress
Mental Health Foundation chief executive Mark Rowland said there needs to be greater awareness of the issue.
"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.
"Women, and particularly young women, are showing the highest rates of distress.
"Significant numbers have felt feelings of disgust and shame or changed their behaviour to avoid situations that make them reflect negatively about their bodies."
But he warned it was not just young people who were affected - one in five people aged over 55 and over said they had felt anxious because of body image.
He also said more needed to be done by social media companies and the advertising industry to promote a diversity of body types. He said there needed to be clear ways to report abuse and bullying online - something the government is looking into.
"Many people identified social media as an important factor causing them to worry about their body image - and the majority of respondents felt the government needed to take more action," he added.