The HEALTHY Study was a randomized controlled trial administered across 42 middle schools across the US. The intervention integrated several themes across nutrition, physical activity, behavior, and communications and social marketing.

The intervention includes 4 separate components:
1) Nutrition/Food Environment Intervention: aimed at changing the "quantity and nutritional quality of food and beverages throughout the total school environment"
2) Physical Education Intervention: aimed at increasing participation and number of minutes spent in moderate-to-vigorous physical activity
3) Behavioral Intervention: aimed at increasing knowledge, enhancing decision-making skills, and to support and reinforce youth in accomplishing goals, and
4) School-Wide Communications Intervention: aimed at enhancing and promoting changes through messages, images, events, and activities.

The Food Environment Intervention was implemented primarily through federal programs such as NSLP (National School Lunch Program) and SBP (School Breakfast Program) and providing a la carte meals and vending machines. This component of the intervention was also enhanced with “messaging, cafeteria-based educational events, taste tests to introduce new food items, and food service staff training sessions.” The Physical Education intervention involved providing lesson plans and equipment, training PE teachers to effectively manage the classroom, and providing PE assistants to advice the teachers. For the Behavioral Intervention, Fun Learning Activities for Student Health (FLASH) were incorporated into classroom settings through scripted materials to assist instructors. In order to involve parents and family members of the students, family outreach newsletters and take-home packages of materials were distributed. The communications component used messages, images, events, and activities to promote positive changes in nutrition, activity, and behavior. Volunteer student peer communicators were “recruited and trained to help deliver this component of the intervention.”

The program was facilitated by members of the HEALTHY Study group, as well as school administrators, teachers, food service staff, PE teachers, and student peer communicators.

The primary goal of the intervention was to reduce overweight and obesity prevalence among middle school students. Ancillary goals were to improve BMI and fasting insulin values, increase water consumption, reduce consumption of beverages with added sugar, increase healthy food choices, improve self-monitoring, and increase exercise time among sixth, seventh, and eighth grade students.

School-based programs that aim to address childhood obesity and adiposity may reduce individuals' risk of developing childhood-onset of non-insulin dependent diabetes mellitus.

During the study period, student attrition rates were identical (27.5%) across both arms of the study. In both the intervention and control schools, there was a decrease in the primary outcome - the combined prevalence of overweight and obesity; however, there was no significant difference between the school groups. The intervention schools reported greater reductions in the secondary outcomes of BMI, percentage of students with waist circumference at or above the 90th percentile, fasting insulin levels (P=0.04 for all comparisons), and prevalence of obesity (P=0.05).