Evaluation of a mobile phone-based diet game for weight control.

We developed an interactive mobile-phone based application, SmartDiet, that analyzes daily nutrition intake and patterns of daily exercise. It provides a personalized diet profile and promotes knowledge about nutrition using a diet game. We evaluated the effectiveness of the SmartDiet application in terms of acquiring dietary information, weight control and user satisfaction. A case-control study was conducted over a six-week period, with 19 people in the intervention group and 17 people in the control group. During the study, a total of 235 successful data transmissions were performed from the mobile phones and there was a mean of 12.4 transmissions per participant. The three body composition measures (fat mass, weight and body mass index) decreased significantly after the intervention in the intervention group, but there were no significant changes in the control group. In a questionnaire survey at the end of the study, the majority of the participants responded that the system was useful for obtaining information and managing the diet process. The SmartDiet mobile weight management application appears to contribute to weight loss in obese adults.