This is usually due to the low percentage of body fat and is a result of starvation. The incessant dieting often leads to abuse of diuretics and laxatives. Anorexia is one of the few psychiatric disorders that can lead to death. Most of the aberrant behavior exhibited in order to loose weight occurs in secret. Therefore, eating in public and with the family decreases, often further straining social relationships as a result, particularly over time and as the anorexia becomes more serious.
Weight reduction is drastic as the intake of food is significantly decreased.
There is a disproportionate decrease in high-carbohydrate and fatty foods while an individual strives for increased weight loss. The onset of anorexia nervosa occurs between the ages of 10 and 30. After the age of 13 the frequency of onset increases rapidly, where the ages of 17 and 18 marks the maximum frequency. About 85 percent of those with anorexia develop the disorder between the ages of 13 and 20 years. Weight loss of at least 15 percent of the original body weight is required for a diagnosis of anorexia.