(P16-036-25) Effectiveness of a Novel Digital Program Promoting Nutrition & Health Habits Formation Among Older Adults: A Proof-of-Concept Behavior Change Intervention

Objectives: This behavior change intervention aimed to test the effectiveness of a new digital nutrition and health program ("Daily 8") on multiple habit formation among older adults. The study also explored the impact of behavior complexity on habit formation and participants' experiences by qualitative interviews.

Methods: The program was designed based on the behavior change theory incorporating goal-directed and habitual behaviors, and tested in a 14-week randomized controlled trial conducted on the WeChat platform. Participants aged 45-75 from 3 cities in China received daily reminders at 8 AM via WeChat, with two modes: "Push Notification Only" (PNO group) and "Push notification plus Group chat Notifications" (PGN group). The PGN group was additionally enrolled in a moderated WeChat group. Participants were assigned 8 health behaviors as daily ‘to do’ goals and used a digital checklist to create a repetitive feedback loop on a daily basis. From week 11 to 14, the group chat was removed, and both groups relied on push notifications. For the behavior of "drinking milk with added phytosterol," participants were provided with fortified milk powder. Habit formation was assessed weekly using the Self-Reported Behavioral Automaticity Index (SRBAI) and weekly behavior frequency (WBF).

Results: The study included 109 participants (median age = 59.0 ± 8.5), with a daily check-in rate as 92.7%. Both groups increased significantly in WBF and SRBAI across the 8 behaviors, with no between-group differences at both Week 10 and Week 14. However, the PGN group showed significantly higher SRBAI increases during weeks 1-3 & 6-7.

Habit formation was defined as meeting both SRBAI > 20 (out of 28) and WBF > 4 days. The behavior of "drinking milk with added phytosterol" reached the cut-off within 3 weeks for the PGN group and 4 weeks for the PNO group. The habit formation of other 7 behaviors occurred between 9 and 14 weeks. Latent growth analysis of SRBAI found 3 behavior change patterns which were significantly associated with age (p = 0.003).

Conclusions: The "Daily 8" program effectively facilitated habit formation, potentially by enabling the transition from goal-directed to habitual behaviors. The product availability simplified behavior complexity, enabled early habit formation, and may nudge for overall behavior changes.

Funding Sources: The study was funded by Société des Produits de Nestlé.