The majority of people have days where they feel dissatisfied with their body or insecure about their appearance, but struggling with the way you look in the long term can be an indication of body dysmorphic disorder (BDD). This mental health condition causes people to worry obsessively about perceived 'flaws' in their appearance. This can be a minor physical imperfection, the importance of which they blow out of perspective, or a problem nobody else can see. It can seriously affect all aspects of life and lead to depression and even suicidal thoughts.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/how-to-deal-with-negative-body-image-in-the-summer