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Why This Topic Is Important
More than one-third (35%) of U.S. children ages 2-19 are overweight or obese, according to a 2017-2018 survey from the Centers for Disease Control and Prevention (1). In recent decades the national childhood obesity rate has more than tripled, with persistent disparities by race/ethnicity and socioeconomic status (1, 2, 3).

Compared with children at a healthy weight, children with obesity are at higher risk for a range of health problems, including asthma, high blood pressure, high cholesterol, and type 2 diabetes; they also are more likely to become obese as adults (4). In addition, childhood obesity is linked to social and emotional difficulties, such as anxiety, depression, stigmatization, bullying, and low self-esteem (4). Obesity's impact also extends beyond the individual. U.S. medical care costs related to adult obesity have been estimated at about $190 billion annually; in California, estimates indicate that a 5% reduction in average adult BMI could save more than $80 billion in obesity-related health costs by 2030 (3).

Many factors contribute to childhood obesity and overweight. The rise has been attributed to changes in food environments that make non-nutritious "junk" food and beverages more available, affordable, and appealing, as well as social and environmental changes that have reduced physical activity among children—e.g., increased sedentary screen time, less physical education, neighborhoods that do not promote walking or riding bikes, and decreased safe places for children to play (2, 3, 4).
Find more information about children's weight in’s Research & Links section.

Sources for this narrative:

1.  Fryar, C. D., et al. (2020). Prevalence of overweight, obesity, and severe obesity among children and adolescents aged 2-19 years: United States, 1963-1965 through 2017-2018. National Center for Health Statistics. Retrieved from:

2.  State of Child Obesity. (2021). From crisis to opportunity: Reforming our nation's policies to help all children grow up healthy. Robert Wood Johnson Foundation. Retrieved from:

3.  California Department of Public Health, & Nutrition Policy Institute. (2016). Obesity in California: The weight of the state, 2000-2014. Retrieved from:

4.  Centers for Disease Control and Prevention. (2021). Childhood obesity causes and consequences. Retrieved from:
Policy Implications
California has been a leader in advancing policies to combat the overweight and obesity epidemic among children, from banning sugar-sweetened beverages and unhealthy foods in schools to requiring nutritious beverages in child care settings and healthy default beverages with restaurant kids' meals (1, 2, 3). Despite these efforts, childhood obesity remains a major public health concern, statewide and nationally, and significant inequities persist, with children of color, low-income children, and those in rural areas disproportionately affected (4, 5, 6).

Reducing childhood obesity requires equitable access to safe places to play, frequent opportunities for exercise in and out of school, available and affordable healthful foods and beverages, and reduced access to and marketing of high-calorie, low-nutrient foods and drinks (4, 5, 7). It also requires an intentional focus on equity and comprehensive, multi-sector strategies, including empowering communities and improving socioeconomic resources for groups at greatest risk (4, 5). Policymakers and other leaders at the local, state, and national levels can promote effective initiatives and strengthen systems, legislation, and environments to prevent and address obesity (4, 5, 6).

Policy and practice options that could promote healthy weight in childhood include:
  • Advancing evidence-based, culturally-tailored practices supporting good nutrition in early childhood, such as home-visiting programs that educate parents and encourage breastfeeding, which has been shown to protect against obesity (8)
  • Promoting increased participation in federal child nutrition programs (such as, among others, school breakfast, lunch, afterschool, and summer meal service), which can improve health and decrease the risk of unhealthy weight gain (9, 10)
  • Supporting comprehensive initiatives in school and child care settings to improve nutrition and physical activity; such efforts should align with existing mandates, expand opportunities for daily exercise, make improvements to available food, integrate nutrition education and physical activities into lesson planning, and engage parents and other stakeholders (11, 12)
  • Continuing to enforce and enhance legislation that restricts the availability of high-calorie, low-nutrient foods and drinks in schools and child care in favor of healthy meals, snacks, beverages, and drinking water, and providing needed support and technical assistance to ensure compliance (1, 2, 3, 5)
  • Continuing to strengthen policies, funding, and planning for a built environment in schools and communities that encourages walking, bicycling, and outdoor play, especially in neighborhoods that lack safe places for physical activity (6, 13)
  • Ensuring that anti-obesity efforts explicitly address racial/ethnic and socioeconomic inequities and work in partnership with under-resourced communities, building social and economic capacity to address issues such as food insecurity (4, 6)
  • Implementing common standards for marketing food and beverages to children and adolescents, and supporting efforts to reduce advertising of sugary drinks and unhealthy foods to young people, particularly youth of color, who are disproportionately exposed to such advertisements (3, 6, 7)
  • Supporting public, parent, and youth education to promote healthy eating and active living (3, 7)
For more policy ideas and research on this topic, see’s Research & Links section or visit State of Childhood Obesity. Also see Policy Implications on under Nutrition and Physical Fitness.

Sources for this narrative:

1.  Lee, D. L., et al. (2020). Status of beverages served to young children in child care after implementation of California policy, 2012-2016. Preventing Chronic Disease, 17, 190296. Retrieved from:

2.  Karpyn, A., et al. (2020). Assessing the implementation of kids' meals healthy default beverage policies in the state of California and city of Wilmington, Del. Healthy Eating Research. Retrieved from:

3.  Wolstein, J., & Babey, S. H. (2018). Sugary beverage consumption among California children and adolescents. UCLA Center for Health Policy Research. Retrieved from:

4.  Kumanyika, S. K. (2019). A framework for increasing equity impact in obesity prevention. American Journal of Public Health, 109(10), 1350-1357. Retrieved from:

5.  State of Child Obesity. (2021). From crisis to opportunity: Reforming our nation's policies to help all children grow up healthy. Robert Wood Johnson Foundation. Retrieved from:

6.  Champion Provider Fellowship. (2018). PSE playbook: Implementing policy, system, and environmental change in our communities. University of California San Francisco & California Department of Public Health. Retrieved from:<

7.  Muth, N. D., et al. (2019). Public policies to reduce sugary drink consumption in children and adolescents. Pediatrics, 143(4), e20190282. Retrieved from:

8.  Isong, I. A., et al. (2018). Racial and ethnic disparities in early childhood obesity. Pediatrics, 141(1), e20170865. Retrieved from:

9.  Food Research and Action Center. (2017). Hunger and health: The role of the federal child nutrition programs in improving health and well-being. Retrieved from:

10.  Food Research and Action Center. (2021). State of the states: Profiles of hunger, poverty, and federal nutrition programs. Retrieved from:

11.  Blondin, K., et al. (2018). Early care and education (ECE) interventions for promoting nutrition and physical activity and preventing obesity. Nutrition Policy Institute. Retrieved from:

12.  Blondin, K., et al. (2018). School-based interventions for promoting nutrition and physical activity and preventing obesity: Overview of studies and findings. Nutrition Policy Institute. Retrieved from:

13.  Lieberman, M., et al. (2020). Making strides: 2020 state report cards on support for walking, bicycling, and active kids and communities. Safe Routes Partnership. Retrieved from:
How Children Are Faring
In 2019, 41% of 5th graders, 40% of 7th graders, and 38% of 9th graders in California had a body mass index or body fat percentage higher than state standards for body composition, figures that have remained relatively stable since 2014. In each grade level, the percentage of boys statewide who are overweight or obese is consistently higher than the percentage of girls.

The share of students who are overweight or obese varies widely by region and race/ethnicity. For example, the percentage of 5th graders who were overweight or obese in 2019 ranged from 24% to 55% across counties with data, and from less than 5% to more than 75% across school districts. In the same period, 50% of Hispanic/Latino 5th graders statewide were overweight or obese, compared with fewer than 30% of their Asian and white peers.