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There’s good news about childhood obesity for a change. A new report from the Centers for Disease Control and Prevention (CDC) hints that efforts to curb weight gain among low-income preschoolers may be working.

Between 2008 and 2011, 18 U.S. states and one territory reported small, but statistically significant declines in obesity among this group of preschoolers. The findings, based on data from12 million children aged two to four years who participate in federally funded maternal- and child-nutrition programs, show that childhood obesity rates in Florida, Georgia, Missouri, New Jersey, South Dakota, and the U.S. Virgin Islands declined by at least a 1%, and 20 other states and Puerto Rico maintained their current rates while only three states saw slight increases. The results are encouraging, since in the U.S., about one in eight preschoolers are obese, and kids are five times more likely to be overweight or obese as adults if they are overweight between the ages of three and five.

“We’ve seen isolated reports in the past that have had encouraging trends, but this is the first report to show many states with declining rates of obesity in our youngest children after literally decades of rising rates,” says Dr. Tom Frieden, director of the CDC.

Frieden credits the turn-around to a combination of more intensive government programs to provide healthy foods to low-income families, as well as greater awareness of the importance of nutrition and healthy weight overall. For example, the the Women, Infants, and Children (WIC) program, which provides nutritious foods and information on healthy eating and health care referrals to low-income pregnant women, promotes breastfeeding and offers whole fruits and vegetables instead of fruit juice. Breastfeeding has been linked in some studies to lower rates of obesity among children, and studies show that kids who eat fresh produce are less likely to turn to the high-calorie, sugary snacks and beverages that have been associated with weight gain. And programs like Let’s Move!, which encourage kids to be physically active, are also helping youngsters to maintain a healthy balance between the amount of calories they eat and the amount they burn off.

The promising findings mirror those among older kids as well; after stalling in recent years, in September 2012 the Robert Wood Johnson Foundation (RWJF) published a report showing childhood obesity rates were trending downward in some U.S. states and cities, despite continuing disparities between socioeconomic and racial groups. New York City, Philadelphia, and cities in Mississippi and California led the decline, with New York City reporting a 5.5% drop in the percentage of obese children between 2007 and 2011, Philadelphia reporting a 4.7% drop, and Los Angeles a 3% decrease. Mississippi–which is consistently one of heaviest states in the nation with a childhood obesity rate of about 41%, reported a 13.3% drop.

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As TIME reported in December of last year, these successful cities and states share some common practices to keep the rising tide of obesity among kids in check. The majority have implemented several comprehensive programs that target both schools and surrounding communities in order to create an environment where healthy foods are accessible and exercise is encouraged. “From this aggregation, it is clear now that any community that makes these kind of changes over a few years will see their children get healthier. We now have enough places that have done this that we can confidently say to communities that if they make these changes, they will see these improvements and more, we hope, over time,” Jim Marks, senior vice president and director of the RWJF Health Group told TIME.

New York City has taken the lead with aggressive efforts — some of which have been more successful than others — to re-structure residents’ eating environments. Fast food restaurants in the city are now required to list calories on their menus, and the city’s health department banned trans fats from restaurant fare. Produce carts are parked at many street corners with low-priced fresh fruit and vegetables, and two New York City hospitals also recently announced that their doctors will start prescribing fruits and vegetables for their patients, along with produce coupons. Mayor Michael Bloomberg‘s attempt to ban on sugared beverages larger than 16 oz. at restaurants, sports arenas and movie theaters, however, was rejected.

Mississippi and California focused on the school system, and adopted nutritional standards that require healthier food, drink and snack options for students, and boosted schools’ physical activity requirements. In 2008, Mississippi launched programs like the Color Me Healthy Program, which teaches childcare providers how to create positive and healthy environments that encourage exercise.

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New federal regulations to improve school lunches have also played a role in slimming down America’s children by placing calorie limits on meals and requiring more fruits, vegetables and whole grains. Anticipating these changes, Carrollton City Schools in Georgia began introducing more whole-grain foods and fresh fruits and vegetables in its cafeteria over the last 12 years. Today, the four schools that make up the district serve 3,860 healthy meals a day and their on-campus nutritionists estimate that produce consumption among its students has increased by up to 40%.

Next year, schools will have even more help in making their menus healthier. The USDA recently announced that schools across the country will have to provide snacks low in fat, sodium and salt in vending machines by the 2014-2015 school year. The snacks can contain no more than 200 calories per item, and sodas and sports drinks sold in high schools can’t exceed 60 calories in a 12-ounce serving. Elementary and middle schools can only sell water, 100% fruit or vegetable juice and low-fat or fat-free milk. Although some schools anticipate a decline in revenues from vending machine sales, schools that have already eliminated unhealthy snacks have offset those losses by holding more school fundraisers.

What’s becoming obvious is that the most successful programs involve as many members of the community as possible, from schools to food vendors, restaurant, grocery stores and even hospitals. Last month, TIME reported on three major hospitals making significant changes in their cities, including Children’s Healthcare of Atlanta. In 2010, a study called F is for Fat identified the state as having the second highest childhood obesity rate in the U.S., behind only Mississippi, based on data from the National Child Health Survey. The hospital network launched a major campaign to tackle the issue, and in the latest report released last year, Georgia ranked 35. Dr. Mark Wulkan, the Surgeon in Chief at Children’s Healthcare of Atlanta who performs minimally invasive surgeries for weight loss on children and performed the first adolescent bariatric surgery in the U.S., told TIME he could no longer watch the suffering of Atlanta’s obese children. As TIME reported:

One morbidly obese child who was referred to Wulkan had such severe sleep apnea that he needed a tracheostomy, or surgical incision into his windpipe, to help him breathe. “Do you know why he came in to get better? He came so he could swim. He hadn’t been swimming in years. Eventually, it just breaks your heart.” Wulkan started a program in 2009 for his patients, called Health4Life, which now treats over 600 kids in Georgia who are in the 95th percentile for body mass index (BMI). But as one of the largest health care providers in the state, Children’s Healthcare of Atlanta also decided it had a responsibility to intervene. That’s how Strong4Life, a comprehensive wellness program designed to treat obesity by addressing all aspects of a child’s environment, from school nutrition to doctor’s visits, was born. “At the time [the education effort] was controversial, because it called a spade a spade. But it got people talking about it and got us to where we are now, and that is that parent awareness [about childhood obesity] is closer to about 40%,” he says.

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While the latest numbers are trending in the right direction, Frieden says communities, states and the federal government can do more to help children maintain healthy weights. “It’s a bright spot for our nation’s young kids but the fight is very far from over. Obesity is a complex problem and addressing it isn’t going to be quick or simple. It’s not going to turn on a dime,” he says.