Ranker's top 10 movies about an eating disorder all focus on girls driven to become too thin. No wonder most people equate the phrase "eating disorder" with anorexia.

But young adults 18-24 who are overweight or obese are more likely to have eating disorders and disordered eating behaviors than their normal or underweight peers (29.3 percent versus 15.8 percent for women; 15.4 percent versus 7.5 percent for men).

They're also far more likely to go undiagnosed and untreated. That's the conclusion of a recent study that looked at 14,322 young adults.

Other studies have found that among overweight/obese folks, the two most common forms of eating disorders are binge eating disorder and night eating syndrome.

In night eating syndrome, 25 percent of daily calories or more are consumed after the evening meal and/or at least three times a week the person gets up from sleeping to eat.

Binge eating disorder — eating more than normal over a period of time and the inability to control eating — shows up in as many as 25 percent of Type 2 diabetes patients and can be joined by disordered eating behaviors, such as vomiting and use of laxatives and diuretics.

If you or a loved one is overweight or obese and are struggling to achieve a healthy weight, it is important to talk with an eating disorder specialist to see if you need to address those challenges before, and then while, you focus on losing weight.