Iowa State will be host a lecture Wednesday by Buck Runyan , director of Remuda Ranch at the Meadows, an eating disorder treatment facility.

According to the Lectures Program, “His presentation is an overview of what eating disorders are and, more importantly, what they are NOT.” The lecture will take place in conjunction with National Eating Disorder and Body Image Awareness Week.

According to the National Eating Disorders Association, eating disorders are defined as “serious illnesses that involve extreme emotions, attitudes and behaviors surrounding food, exercise and body image.” The NEDA also states that 30 million Americans will suffer from an eating disorder at some point in their lives.

Here’s a quick rundown of three major eating disorders and the behaviors that can identify them.

Binge eating disorder

Binge eating disorder is characterized by “recurrent episodes of eating large quantities of food (often very quickly and to the point of discomfort); a feeling of a loss of control during the binge; experiencing shame, distress or guilt afterward; and not regularly using unhealthy compensatory measures (e.g., purging) to counter the binge eating,” according to the NEDA. Binge eating episodes are characterized by both a lack of control when eating and eating an amount of food in a certain period of time that is larger than would be considered normal in similar situations.

Some warning signs of BED include:

• fear of eating in front of other people

• secret recurring episodes of binge eating

• fluctuations in weight and disruption in normal eating habits.

Binge eating disorder is the most common eating disorder in America, and while it can be severe and life-threatening, it is also very treatable.

Bulimia nervosa

According to the NEDA, bulimia nervosa is defined as “a cycle of bingeing and compensatory behaviors such as self-induced vomiting designed to undo or compensate for the effects of binge eating.”

According to the DSM-5, the American Psychiatric Association’s tool for classifying and diagnosing mental illness, the official criteria for a bulimia nervosa diagnosis include:

• recurrent episodes of binge eating

• Recurrent inappropriate compensatory behavior in order to prevent weight gain, such as self-induced vomiting, misuse of laxatives, diuretics, or other medications, fasting, or excessive exercise.”

The NEDA also states that at any point in time, 1 percent of women and 0.1 percent of men will meet the DSM-5 criteria for bulimia nervosa. Some warning signs of bulimia nervosa include:

• Evidence of binging and purging behaviors (frequent trips to the bathroom after meals).

• Developing food rituals (eating only a certain food/from a certain food group).

• Cavities and discoloration of teeth.

Anorexia nervosa

Anorexia nervosa is characterized by “weight loss (or lack of appropriate weight gain in growing children); difficulty maintaining an appropriate body weight for height, age and stature; and, in many individuals, distorted body image,” according to the NEDA. Anorexia nervosa can affect people of all ages, but the number of children and older adults diagnosed with the disorder is increasing.

According to the DSM-5, the following criteria must be met in order to be diagnosed with anorexia nervosa:

• Restriction of energy intake relative to requirements leading to a significantly low body weight in the context of age, sex, developmental trajectory and physical health.

• Intense fear of gaining weight or becoming fat, even though underweight.

• Disturbance in the way in which one’s body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or denial of the seriousness of the current low body weight.

Some warning signs of anorexia nervosa include:

• Dramatic weight loss.

• Is preoccupied with weight, food, calories, fat grams and dieting.

• Makes frequent comments about feeling “fat” or overweight despite weight loss.