Most Mainers know by this time that far too many of us are overweight or obese. And they know that these conditions can shorten life and lead to various diseases as well as costing us all in bearing a public health burden. What many have yet to realize is that a dread of putting on too much weight can have its own costly consequences. As The Wall Street Journal warned in a recent report, “Millions of young Americans are literally starving themselves to death.”

The federal Office on Women’s Health says that eating disorders are increasing, especially among young white females, including girls as young as 9 years old. Other ethnic groups and boys also are victims, though on a lesser scale.

Fortunately, researchers have learned much about the causes of eating disorders and the use of drugs and counseling to treat them. But detecting these illnesses early is difficult because the victims often blame themselves and conceal the problem.

Specifically, these eating disorders are mainly two different ailments. Anorexia nervosa is a serious, potentially life-threatening eating disorder involving self-starvation and excessive weight loss. Bulimia nervosa, similarly serious and life threatening, involves a cycle of binge eating followed by self-induced vomiting or excessive use of laxatives.

In Maine, the incidence among high school students goes up and down, according to a sample taken every two years, the Maine Youth Risk Behavior Survey. In 2003, it found that 7.1 percent of girls and 4.5 percent of boys vomited or took laxatives to lose weight or keep from gaining weight during a 30-day period. The difference in percentages is not considered statistically significant.

The nonprofit Eating Disorders Association has begun a new awareness campaign with the theme “Get Real.” It uses print and television ads showing a girl with a skeleton for a body looking in a mirror and complaining, “I’m so fat.”

It says that in the United States as many as 10 million females and 1 million males are “fighting a life and death battle” with these diseases, while another 25 million are binge eaters.

The Eating Disorders Association advises students to “Listen to your body,” “Eat when you’re truly hungry, and stop when you are full,” avoid weight-loss diets, and “Declare your independence from a weight-obsessed world.” It advises young people to view the media critically and beware of the daily bombardment of media messages that push “narrow definitions of beauty and acceptability.” In other words, don’t let those bone-thin actresses and models set your standards.

Above all, parents and friends should watch for signs of eating disorders and get prompt help from doctors and counselors. Authorities say 80 to 90 percent of the cases respond to treatment, but it can take as long as two years. Nagging a daughter to “Eat!” or “Don’t eat” won’t help. Treatment is a job for experts.