There is no single cause of these conditions. It is currently agreed that eating disorders are multi factorial - with social, psychological and biological factors all playing a part in varying degrees for different people.

Contributing factors may include:

Social factors, such as:

■   media and other presentations of the “ideal” shape in western societies as slim and fit, and a tendency to stereotype fat people in a negative manner
■   mixed messages about health foods and fast foods; confusion about good nutrition and healthy eating
■   pressure to achieve and succeed
■   professions with an emphasis on body shape and size

Psychological factors:

■   major life changes or events such as adolescence, relationship breakdowns, child birth, the death of a loved one; or the accumulation of many minor stressors
■   fear of the responsibilities of adulthood
■   a belief that love from family and friends is dependent on high achievement
■   poor communication between family members, or the reluctance of parents to allow appropriate degrees of independence as children mature

Biological factors:

■   adolescence and the associated physical changes
■   genetic or familial factors