The impact of a multilevel childhood obesity prevention intervention on healthful food acquisition, preparation, and fruit and vegetable consumption on African-American adult caregivers

Objective: To evaluate the secondary impact of a multilevel, child-focused, obesity intervention on food-related behaviours (acquisition, preparation, fruit and vegetable (FV) consumption) on youths' primary caregivers. Design: B'More Healthy Communities for Kids (BHCK) group-randomized controlled trial promoted access to healthy foods and food-related behaviours through wholesaler and small store strategies, peer mentor-led nutrition education aimed at youths, and social media and text messaging targeting their adult caregivers. Measures included caregivers' (n 516) self-reported household food acquisition frequency for FV, snacks and grocery items over 30 d, and usual FV consumption in a sub-sample of 226 caregivers via the NCI FV Screener. Hierarchical models assessed average treatment effects (ATE). Treatment-on-the-treated-effect (TTE) analyses evaluated correlation between behavioural change and exposure to BHCK. Exposure scores at post-assessment were based on self-reported viewing of BHCK materials and participating in activities. Setting: Thirty Baltimore City low-income neighbourhoods, USA. Participants: Adult caregivers of youths aged 9-15 years. Results: Of caregivers, 90.89 % were female; mean age 39.31 (sd 9.31) years. Baseline mean (sd) intake (servings/d) was 1.30 (1.69) fruits and 1.35 (1.05) vegetables. In ATE, no significant intervention effect was found on caregivers' food-related behaviours. In TTE, each point increase in BHCK exposure score (range: 0-6.9) increased caregivers' daily fruit consumption by 0.2 servings (0.24 (se 0.11); 95 % CI 0.04, 0.47). Caregivers reporting greater social media exposure tripled their daily fruit intake (3.16 (se 0.92); 95 % CI 1.33, 4.99) and increased their frequency of unhealthy food purchasing v. baseline. Conclusions: Child-focused community-based nutrition interventions may also benefit family members' fruit intake. Child-focused interventions should involve adult caregivers and intervention effects on family members should be assessed. Future multilevel studies should consider using social media to improve reach and engage caregiver participants.