The long-term effects of primary school-based obesity prevention interventions in children: A systematic review and meta-analysis

Baseline higher hair cortisol moderated some effects in a healthy lifestyle intervention

Children and families from socioeconomically marginalized background experience high levels of stress, especially persistent chronic stress, due to unstable housing, employment, and food insecurity. Although consistent evidence supports a stress-obesity connection, little research has examined the potential moderation role of stress in childhood obesity interventions. Therefore, this study aimed to explore how chronic stress (hair cortisol) moderated the effects of a healthy lifestyle intervention on improving behavioral and anthropometric outcomes among 95 socioeconomically marginalized parent-child dyads. Data were collected in a cluster randomized controlled trial with 10 Head Start childcare centers being randomized into intervention and control. The child sample (3-5 years old) included 57.9 % female, 12.6 % Hispanic, and 40.0 % Black. For the parents, 91.6 % were female, 8.4 % were Hispanic, 36.8 % were Black, and 56.8 % were single. Parent baseline hair cortisol significantly moderated the intervention effects on child fruit intake (B = -1.56, p = .030) and parent nutrition self-efficacy (B = 1.49, p = .027). Specifically, higher parent hair cortisol lowered the increases in child fruit intake but improved the increases in parent nutrition self-efficacy in the intervention group compared to control group. Child higher baseline hair cortisol was significantly associated with the decreases in child fruit intake (B = -0.60, p = .025). Child baseline hair cortisol significantly moderated the intervention effects on parent physical activity (PA) self-efficacy (B = -1.04, p = .033) and PA parental support (B = -0.50, p = .016), with higher child hair cortisol decreasing the improvement on these two outcomes in the intervention group compared to control group. Results from this study shed lights on the moderation role of chronic stress on impacting healthy lifestyle intervention effects. Although needing further investigation, the adverse effects of chronic stress on intervention outcomes should be considered when developing healthy lifestyle interventions for preschoolers and their families.

Nutrition Interventions for Pediatric Obesity Prevention: An Umbrella Review of Systematic Reviews

Nutrition interventions to prevent pediatric obesity can help to establish healthy habits to improve current and future health. The objective of this umbrella review of systematic reviews (SRs) is to examine the impact of obesity prevention interventions with a nutrition component on body mass index measures, overweight/obesity prevalence, and cost-effectiveness in participants 2-17 years old. Grading of Recommendations Assessment, Development and Evaluation (GRADE) methods were used, and this umbrella review was registered on PROSPERO (CRD42023443033). Included SRs were required to search ≥2 databases and to assess the risk of bias (RoB) of primary studies, and they were published 2017-June 2023. Database searches identified 4776 articles, and 31 SRs were included. In all age groups combined, interventions with both nutrition and physical activity were effective and cost-effective in all settings combined, and in the community setting specifically. In children ≤5 years old, interventions in the home and family, community, and healthcare settings demonstrated some efficacy, whereas in children 6-12 years old, school interventions were most effective. Evidence with individuals 13-17 years was limited. The certainty of evidence was generally low due to RoB in included studies, inconsistency, and imprecision. Pediatric obesity prevention interventions with nutrition should be tailored to the developmental stage to ensure appropriateness and efficacy.