Eating disorders: clinical features and diagnosis

Eating disorders are widely thought of as modern problems arising as a consequence of a Western culture that values, especially for women, being thin. Yet history suggests that these disorders are not a new phenomenon — there have been reports of young women restricting their food intake as early as the Middle Ages (the so-called Fasting Saints). Anorexia nervosa (described below) has also been identified in diverse contemporary cultures, including African and East Asian. It is worth noting that not only young women suffer from eating disorders — an estimated one in 2,000 men in the UK suffer from anorexia nervosa at some time in their lives. Although core clinical features of eating disorders, such as low weight, endure across history and geography, the underlying beliefs often vary. For example, in nonWestern cultures beliefs relating to the pursuit of thinness are uncommon. The notion that these disorders can be explained by cultural influences alone is further challenged by the substantial genetic contribution to risk. Indeed, the causes are complex and involve interactions between genetic, neurobiological and psychological factors. Anorexia nervosa (AN) was described first in the late 19th century. Derived from Greek, it literally means “without appetite” with an underlying “nervous” or psychiatric cause. Bulimia nervosa (BN) was used later to describe individuals with a pattern of binge eating followed by purging behaviours. It originates from the Greek word boulimia (bous meaning “ox” and limos meaning “hunger”) and implies a ravenous hunger.