Changes in body weight, awareness, and behaviors among workers participating in an online specific health guidance program incorporating multiple nudges: a process evaluation

Abstract Objectives In Japan, specific health guidance (SHG) — comprising intensive and motivational support — has increasingly incorporated nudges and online modalities to prevent metabolic syndrome. This practice aimed to conduct a process evaluation of an online SHG program that integrated multiple nudges by examining changes in body weight, health awareness, and health-related behaviors. Methods A 100-day online SHG program was conducted within a health insurance association of a Japanese securities firm. The program included three group seminars, individual counseling, self-monitoring via a mobile application, and distribution of video content. In addition to health education, multiple nudges (eg, implementation intention and commitment nudges) were embedded throughout the program. Results The analysis included 181 respondents (94 intensive; 87 motivational) who completed follow-up surveys. Improvements were observed across most outcomes; for example, 51.4% of participants experienced weight reduction (56.4% in the intensive group and 46.0% in the motivational group). Notably, the proportion of participants engaging in self-weighing more than once per week increased substantially, from 39.4% to 83.0% in intensive support group (Cohen’s h=0.93), and from 49.4% to 77.0% in motivational support group (Cohen’s h=0.58). Conclusions The combination of multiple nudges and health education can have promoted engagement in healthy behaviors. This practice has limitations such as not assessing long-term outcomes. To overcome them, a longitudinal study using multi-year health checkup data is planned.