Can You Be Too Thin? It’s certainly possible to be dangerously
thin. Individuals with eating disorders such as anorexia nervosa
and bulimia—and those with wasting diseases such as cancer,
AIDS, and heart failure—can lose so much weight that they don’t
have enough energy or basic building blocks to keep themselves
alive. What about people who are thin but don’t have an eating
disorder? Some studies suggest that the connection between body
mass index and premature death follows a U-shaped curve. This
would mean that weighing too much—or too little—isn’t as healthy
as some middle weight. The main problem with this idea is that
most of these studies included smokers and individuals with
early but as-yet undetected chronic and fatal diseases.
Cigarette smokers as a group weigh less than nonsmokers, in part
because smoking deadens the appetite. Potentially deadly chronic
diseases such as cancer, emphysema, kidney failure, and heart
failure can cause weight loss even before they cause symptoms
and have been diagnose