Effects of Smartphone-Based Remote Interventions on Dietary Intake, Physical Activity, Weight Control, and Related Health Benefits Among the Older Population With Overweight and Obesity in China: Randomized Controlled Trial

Background: Traditional health management requires many human and material resources and cannot meet the growing needs. Remote medical technology provides an opportunity for health management; however, the research on it is insufficient. Objective: The objective of this study was to assess the effects of remote interventions on weight management. Methods: In this randomized controlled study, 750 participants were randomly assigned to a remote dietary and physical activity intervention group (group DPI), remote physical activity intervention group (group PI), or control group (group C). At baseline (time 1), day 45 (time 2), and day 90 (time 3), data were collected, including data on dietary intake, physical activity, indexes related to weight control, and health benefits. Results: A total of 85.6% (642/750) of participants completed the follow-up. Compared with group C, group DPI showed a significant decrease in energy intake (-581 vs -82 kcal; P<.05), protein intake (-17 vs -3 g; P<.05), fat intake (-8 vs 3 g; P<.05), and carbohydrate intake (-106.5 vs -4.7 g; P<.05) at time 3. Compared with time 1, groups DPI and PI showed a significant decrease in cereal and potato intake (P<.05). Compared with time 1, the physical activity levels related to transportation (group PI: 693 vs 597 metabolic equivalent [MET]-min/week, group C: 693 vs 594 MET-min/week; P<.05) and housework and gardening (group PI: 11 vs 0 MET-min/week, group C: 11 vs 4 MET-min/week; P<.05) in groups PI and C were improved at time 3. Compared with groups PI and C, group DPI showed a significant decrease in weight (-1.56 vs -0.86 kg and -1.56 vs -0.66 kg, respectively; P<.05) and BMI (-0.61 vs -0.33 kg/m(2) and -0.61 vs -0.27 kg/m(2), respectively; P<.05) at time 2. Compared with groups PI and C, group DPI showed a significant decrease in body weight (-4.11 vs -1.01 kg and -4.11 vs -0.83 kg, respectively; P<.05) and BMI (-1.61 vs -0.40 kg/m(2) and -1.61 vs -0.33 kg/m(2), respectively; P<.05) at time 3. Compared with group C, group DPI showed a significant decrease in triglyceride (-0.06 vs 0.32 mmol/L; P<.05) at time 2. Compared with groups PI and C, group DPI showed a significant decrease in systolic blood pressure (-8.15 vs -3.04 mmHg and -8.15 vs -3.80 mmHg, respectively; P<.05), triglyceride (-0.48 vs 0.11 mmol/L and -0.48 vs 0.18 mmol/L, respectively; P<.05), and fasting blood glucose (-0.77 vs 0.43 mmol/L and -0.77 vs 0.14 mmol/L, respectively; P<.05). There were significant differences in high-density lipoprotein cholesterol (-0.00 vs -0.07 mmol/L; P<.05) and hemoglobin A(1c) (-0.19% vs -0.07%; P<.05) between groups DPI and C. Conclusions: Remote dietary and physical activity interventions can improve dietary intake among participants with overweight and obesity, are beneficial for weight control, and have potential health benefits.