January marks a time when patients often make New Year’s resolutions to improve their health via nutrition, weight loss, and exercise, and many clinicians may find their patients eagerly reporting use of smartphone applications and wearable fitness trackers in the early part of the year. But how helpful are these technologies in improving adherence to dietary and physical activity intervention strategies, particularly compared to low-tech versions like manual food and exercise diaries? What do clinicians need to know to best advise their patients on adopting technology for lifestyle changes — especially to maintain these healthy habits in the long run?  

Although there is much anecdotal support for the role of health apps in improving exercise and weight loss outcomes, research on their safety and efficacy is severely limited due to wide variations in the types of tracking apps for a range of mobile devices. Apps for input of food and beverages consumed, such as MyFitnessPal, MyPlate, or SparkPeople, differ greatly in terms of available foods in the databases, user interfaces, compatible devices, and free or premium features. Because of this, systematic reviews and meta-analyses are often conducted in order to assess the effect of smartphone apps and wearable devices for weight loss. A recent review of 12 published articles discovered that use of a mobile phone app to promote weight loss and physical activity was associated with significant changes in body weight and body mass index of -1.04kg (95% CI -1.75– -0.34) and -0.43kg/m2 (95% CI -0.74–-0.13; I2 = 50%) compared to controls, respectively. However, there was no significant difference in physical activity between the study participants who used apps and those who did not, which may indicate that use of these apps may not actually encourage greater physical activity.1 A second systematic review found that four studies indicated that these apps can assist in increased knowledge and behavioral outcomes related to nutrition, but that these outcomes were inconsistent.2