Anorexia nervosa is an eating disorder and a serious mental health condition.
People with anorexia have problems with eating, meaning they are very anxious about their weight and keep it as low as possible by strictly controlling and limiting what they eat.
Many people will also exercise excessively to lose weight.
Some people will also binge eat, i.e. they eat a lot of food in a short space of time, they then try to get rid of the food from their body by vomiting or using laxatives.
Symptoms usually begin gradually, such as adopting a restrictive diet and often spiral out of control quickly.
Anorexia nervosa is the leading cause of mental health-related deaths.
Most cases of anorexia develop in girls and women usually during the teenage years. Anorexia also affects 1 in every 2,000 men.
The cause of anorexia nervosa is unknown, but most experts believe the condition results from a combination of biological, psychological and environmental factors.
Around 20-30% of people with anorexia do not respond to treatment, and around 5% will die from complications caused by malnutrition.