Body dysmorphic disorder (BDD) is a preoccupation with the appearance of a certain part of the body.
People with BDD are excessively worried about a part of their body which they perceive to have a defect. They continue to believe this despite reassurances about their appearance.
The cause of BDD is unclear, but it may be genetic or caused by a chemical imbalance in the brain.
Treatment may include antidepressant medication, cognitive behavioural therapy or a combination of both. Anti-psychotic medication is sometimes used.
It's difficult to prevent BDD from developing since its cause remains unclear.