A health management system provides instantaneous feedback as to the relationship of food items and exercise to one's fitness level, including one's weight. The health management system does not require the user to count calories, either on the intake or expenditure side of the weight loss paradigm. Rather, the health management system may use icons and graphic displays, without units, to provide a user-friendly interface. The health management system can integrate weight, food intake and activity and can learn the individual's unique response to each element to predict the direction of weight gain or loss.