Health
The cause of BDD is unclear, but it may be genetic or caused by a chemical imbalance in the brain.
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.
Any area of the body may be involved in BDD, but the face is the most common.
People with BDD may not be able to hold down a job and sometimes avoid socialising. They can also find it difficult to have relationships.
BDD is believed to affect at least one per cent of the UK population. It's more common in people with a history of depression and/or social phobia. It often occurs with obsessive-compulsive disorder or generalised anxiety disorder. It may also exist alongside an eating disorder.
It usually starts in adolescence when people are most sensitive about their appearance.
Treatment may include antidepressant medication, cognitive behavioural therapy or a combination of both. Antipsychotic medication is sometimes used.
It's difficult to prevent BDD from developing since its cause remains unclear.