What are the main types of eating disorders?

There are three main types of eating disorders: anorexia nervosa, bulimia nervosa, and binge eating disorder.
Anorexia is associated with a distorted body image, like thinking you are fat even though you are underweight. Serious health consequences can result from starvation and about 1% (or one out of 100) women between the ages of 10 and 20 have anorexia.
Bulimia is characterized by recurrent episodes of binge eating (rapid consumption of vast amount of food in a short period of time), alternated with purging (self-induced vomiting or usage of laxatives). About 4% (or four out of one hundred) of college-aged women have bulimia.
Binge eating disorder refers to a pattern of consumption of large amounts of food even when a person is not hungry. About 1% of women have binge eating disorder, as well as 30% of women who seek treatment to lose weight

What are the risk factors for eating disorders?

You might develop unhealthy eating habits in your efforts to control or alleviate emotional difficulties and unconsciously turn to food to ease your pain or exert some control over your life. Common circumstances and risk factors that contribute to the development of eating disorders include:

• Family problems or a troubled home life
• Major life changes like divorce, death of a loved one, puberty, moving to a new place, starting high school, etc
• Romantic or social problems
• Physical or sexual abuse or trauma
• Psychological Factors like low self-esteem, depression, anxiety, anger, or loneliness
• Interpersonal Factors like difficulty in expressing emotions and feelings, history of being teased or ridiculed based on size or weight
• Social Factors like cultural pressures that glorify "thinness" and obtaining the "perfect body"

In some individuals with eating disorders, the brain chemicals that control hunger, appetite, and digestion may be imbalanced. In this case a Nutritionist might be able to help through prescribing some specific supplements.