More than 1 in 4 adults in California are obese, increasing from 19.3% in 2001 to 28.2% in 2021.

That translates into 8.4 million obese adults in the state, in 2021, according to the California Health Interview Survey (CHIS). An additional 10 million adults were overweight. Among teens, nearly 1 in 5 in the state were either overweight or obese (about 600,000 in each category).

UCLA CHPR researchers have studied increases in obesity for nearly 30 years — by various sociodemographic factors, including age, race and ethnicity, generation, and more — as well as related health outcomes such as diabetes.

Our analysis has looked not only at the increase and the health disparities among those who are overweight and obese, but at the factors that contribute to those conditions: food deserts in poor communities, dearth of healthy food choices in schools, neighborhoods without nearby parks for physical recreation or that are unsafe for play.

Our researchers have published notable studies on sugary drinks. They first looked at soda and sugary drink consumption and found adolescents (ages 12–17) were the biggest consumers, with 62% (over 2 million youths) drinking one or more sodas every day — the equivalent of consuming 39 pounds of sugar each year in soda and other sugar-sweetened beverages. A later study showed that a decrease in soda consumption among children under 12 years old was offset by an increase in other sugary beverages, such as sports drinks.

Evaluations and events that involved UCLA CHPR include:

  • A nutrition education and obesity prevention program (SNAP-Ed) in two high-need areas of Los Angeles that evaluated the long-term impacts of nutrition education, farmers’ markets, healthy retail, community gardens, and healthy food and beverage standards
  • A roundtable with experts who discussed the prevalence and hazards of consuming food with added sugar

Creation of a “retail food environment index” to examine the link between higher concentrations of less healthy food outlets and fast food consumption.

Overweight and Obesity at a Glance


of children and teens were not within walking distance of a park, playground, or open space in 2019 (Source: CHIS)

1.1 million (3.6%)

adult Californians could not find fresh fruit or vegetables in their neighborhood in 2018 (Source: CHIS)

1 in 5 (19%)

children and teens had 2 or more glasses of a sugary, non-soda drink in one day in 2018, compared with 7.5% in 2015 (Source: CHIS)