Utah’s children have the lowest obesity rates in the nation in nearly every age group, according to a report released Thursday.

Just 8.7% of Utah children ages 10 to 17 are obese, compared to a national average of 15.3%, according to “State of Childhood Obesity,” a report released Thursday by the Robert Wood Johnson Foundation. No other state had a lower obesity rate for that age group. Mississippi had the highest overall youth obesity rate, at 25.4%.

The report defines obesity as a body mass index (weight divided by height) in the 95th percentile of children of the same age and sex.

Nationally, youth obesity rates did not change much from 2016 to 2018, when the most recent data was gathered, the report said.

At 8.2%, Utah also had the lowest rate of obesity among 2- to 4-year-olds who participate in the federal government’s Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Nationally, the rate of obesity among those children was 13.9% — a two-point decline from 2010 to 2016.

All racial and ethnic groups studied showed significant decline in obesity rates during that time, the report states.

Among high school students, Utah had the second-lowest obesity rate, at 9.6%. Only Colorado, at 9.5%, had a lower rate. Nationally, the obesity rate among high-schoolers was 14.8%.

“In many ways, obesity reflects larger, systemic problems regarding health and equity,” the report said. “The underlying causes of obesity range from economic, policy, and environmental influences, to cultural norms, and individual factors.

"For example, where families and children live, learn, work, and play have a great impact on the choices available to them. When communities lack fresh, affordable, healthy foods or safe, accessible opportunities to get outside, healthy eating and physical activity can be out of reach for many children.”

Adult obesity rates in Utah were higher than for children, and compared less favorably nationwide. Although Utah’s adult obesity rate of 27.8% is lower than most other states, 10 states and the District of Columbia had lower adult obesity rates. At 23%, Colorado had the lowest adult obesity rate.