Objective: Dietary self-monitoring is linked to improved weight loss success. Mobile technologies, such as smartphone applications (apps), might allow for improved dietary tracking adherence. The authors assessed the use of a popular smartphone app for dietary self-monitoring and weight loss by comparing it with traditional diet counseling and entry methods.
Methods: Diet tracking and weight loss were compared across participants during an 8-week weight loss trial. Participants tracked intake using 1 of 3 methods: the mobile app “Lose It!”, the memo feature on a smartphone, or a traditional paper-and-pencil method.
Results: App users (n = 19) recorded dietary data more consistently compared with the paper-and-pencil group (n = 15; P = .042) but not the memo group (n = 13). All groups lost weight over the course of the study (P = .001), and no difference in weight loss was noted between groups.
Conclusions and Implications: Smartphone apps could represent a novel and feasible dietary self-monitoring method for individuals.
Alex’s Notes: We have previously learned that there are many smartphone apps on the market to promote physical activity, of which I use JetFit to track my training sessions. Now it appears that researchers are turning their attention to the use of these apps for dietary purposes as well. It makes sense when we think about it; dietary monitoring is compromised by reliance on accurate recall, lack of reporting consistency, and the general burden of data logging. Yet, smartphone apps allow for rapid logging with real-time data feedback.
The study at hand recruited healthy, weight-stable adults (42-years; 30 BMI) from the college campus community. They were free of unresolved medical conditions and did not take medications or supplements known to affect body weight.
“Participants were stratified by age, BMI, and gender and semi-randomized into 3 groups: the app group (AP) (n = 19), trained to use the diet-tracking “Lose It!” app daily; the memo group (ME) (n = 18), trained to track dietary intake daily through use of the memo function on their smartphones; and the paper group (PA) (n = 20), trained to record dietary intake daily using a traditional paper-and-pencil method.”
The subjects in the ME and PA groups received personalized feedback via one-on-one nutrition counseling sessions before the start of the study and received weekly emails during the course of the study to encourage healthy eating. Moreover, a personalized written diet plan was developed for each ME and PA participant. Conversely, no dietary advice was provided to the AP group, but instead these subjects received immediate feedback regarding calorie intake when dietary data was entered into the “Lose It” application.
The 8-week study began with 57 participants, but five from both the ME and PA groups dropped out because of time constraints, resulting in a total completion number of 47 people. This created the first statistically important result: there was no attrition in the AP group, suggesting that it did not interfere with daily life significantly. Moreover, both the ME and PA groups reported twice the number of missing days than the AP group (21 vs. 10 days, respectively). Thus, it does indeed appear that recording food in an app is more convenient.
However, the average weight loss between all the groups was not different. There was indeed a significant average weight loss of about 4.6 lbs over the eight weeks, but this simply didn’t differ by group. On the other hand, those in the ME and PA groups improved their diet as judged by the healthy eating index (HEI), whereas it showed a small decline in the AP group over the course of eight weeks, suggesting an importance to counseling sessions for the discussion of dietary practices.
Overall, this brief study supports the notion that smartphone apps offers a less burdensome method for tracking data compared with paper-and-pencil tools. This is critically important because success of mobile devices for self-monitoring will depend in part on the extent to which they facilitate more consistent data entry. That said, this study also demonstrates the limitations of these apps. While they are effective for facilitating weight-loss and possibly other weight-oriented goals, they fail to address the “quality” issue of diet. This has been supported in other randomized controlled trials that demonstrate PDA-based diet tracking in combination with telephone-based counseling programs to significantly improve weight-loss over 12 months in overweight and obese adults compared to the counseling program alone.
For those interested, I personally use an application called FatSecret. As an added benefit, it has an online component as well, with seamless integration between the web and the phone-app.