Activity trackers that monitor daily input and output of calories are helping many people jumpstart an exercise routine and become more active. In a society that has become increasingly inactive and overweight, activity trackers are generally considered to be a positive influence. However, activity trackers can be a risk for people living with eating disorders or in the process of recovery from eating disorders. This is because the nature of these trackers and their emphasis on quantifying what we consume and what we burn plays right into the obsessive and compulsive nature of these disorders. Dangerous Obsession With Numbers Activity trackers are all about the numbers, and eating disorders also frequently become all about the numbers: about making the number of calories consumed go down, the number of calories burned go up and, all importantly, the number of pounds go down. People with anorexia or bulimia nervosa become compulsive about dieting or about purging their calories and feel the need to continue \u201cimproving\u201d these numbers. People with eating disorders are never satisfied with losing a certain amount of weight or reaching a certain measurement -- they become obsessed with making those numbers continually get smaller. As a result, avoiding numbers and the quantification of food and exercise becomes critical to recovering from an eating disorder. Individuals in recovery need to abandon the idea that these numbers are important measures of their health and progress. Instead, they need to focus on the overall state of their health and well-being: how they feel both physically and emotionally. Dark Side of Supposedly Healthy Habits Part of the attraction and the success of activity trackers lies in the fact that they are somewhat addictive, or at least habit-forming, by nature. Seeing the numbers day after day provides strong motivation to work just a little bit harder in order to continue improving. For most people, this does not develop into an unhealthy obsession, although some experts warn that activity trackers are leading people to form habits around the devices themselves rather than around exercise and healthy eating. But for people with eating disorders or recovering from eating disorders, activity trackers can add major fuel to an obsession with dieting, exercising and losing weight that is already burning strongly. It can also fuel such people\u2019s negative feelings about themselves when they fail to meet the extremely unrealistic goals that they will often set for themselves. People who have well-defined fitness or weight goals may be able to get a great deal of benefit from activity trackers and be able to use them as motivation to get where they want to be more quickly. But the nature of eating disorders means that sufferers will never have an ultimate goal\u2014they will never reach a weight or activity level that is acceptable. The distorted self-image and the need for control and perfection that characterizes eating disorders means that those with such an illness will never be satisfied and will never stop trying to lose weight. Ultimately, this may cause people with eating disorders to become seriously\u2014even life-threateningly\u2014unhealthy that much more quickly. This can lead to a number of major health problems and can also increase the risk that someone with an eating disorder will not be diagnosed and get the help that he or she needs before seriously damaging his or her health.