Background: Childhood obesity represents a public health crisis in the United States, affecting 13.9% of preschool-aged children. Most pathophysiologic mechanisms leading to obesity are introduced in early childhood, making this a critical period to consider. The Food and Fitness Initiative (FFI) is a community-based wellness program that focuses on healthy eating and physical activity, implemented in Northeast Iowa. A previous study showed that FFI lowered the rate of increase of body mass index (BMI) levels in school-aged children exposed to the initiative. Our aim is to describe the impact on BMI after implementing FFI in a Northeast Iowa Community Action Head Start (HS) population. Methods: Since 2009 FFI has served more than 100,000 people from high-risk/low-income communities to promote access to healthy, locally grown foods; and opportunities for physical activity. Since 2013, FFI wellness policies of decreasing sweetened beverage intake and screen time and increasing physical activity and family healthy lifestyle activities, have been integrated into HS curriculums. Retrospective BMI data from all children at 14 HS sites between 2012-18 was collected by our study team, from HS files. Children were mostly from single-parent families (51%), between 3 and 4 years old (85%) and Caucasian (70%). Children with BMI assessments during July-December during both their first and second year in HS were included in the analysis. Overweight and obesity prevalence and BMI changes between year 1 and 2 in HS were analyzed. Results: Data from 1013 children were collected, 850 (84%) had qualifying BMI measurements during their first year in HS and 352 of those children (41%) had follow-up data in their second year. There was a decrease in mean BMI between the initial (16.70) and the second year (16.55) in HS that approached statistical significance (t = 1.83, P = .07, d = .10; Table 1). Changes in BMI did not vary by year (F = .45, P = .85, ηp2 = .01). Overweight and obesity prevalence are shown in table 2. There were no statistically significant changes in the percent of overweight (Wald χ2 = .50, P = .48) or obese (Wald χ2 = 1.71, P = .19) children. Changes in overweight (Wald χ2 = 1.98, P = .85) or obese (Wald χ2 = 2.18, P = .82) status did not vary by year. Conclusion: A community-based wellness policy can be successfully implemented into HS curriculum. We found a small trend toward improvement in BMI between year 1 and 2 of programing but not to a statistically significant level. Longer-term follow-up is needed to determine if obesity interventions in the HS setting can bring positive impact in BMI. Further research should focus on how healthy lifestyle interventions integrated into Head Start curriculums can modify obesity and overweight prevalence.

HS Y1 and HS F/U: represent population at the beginning of the school year