Obesity rates among young children enrolled in a federal food assistance program have fallen in 41 American states and territories, according to the Centers for Disease Control and Prevention.

In a report released this week, researchers found the obesity rate among more than 12.4 million 2- to 4-year-olds enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) dropped from 15.9 percent in 2010 to 13.9 percent in 2016.

Obesity fell by more than 3 percentage points in seven states and territories (New Jersey, New Mexico, Utah, Virginia, Guam, Northern Mariana Islands and Puerto Rico) and rose modestly in only three (Alabama, North Carolina and West Virginia).

The drop in obesity, according to the CDC, was significant across all racial and ethnic groups studied. This follows on national data released this summer that showed continued obesity declines overall and across all racial and ethnic subgroups.

The cause for this good news? Starting in 2009, WIC state agencies were required to provide food packages that hewed more closely to the U.S. Dietary Guidelines for Americans as well as infant feeding practice guidelines of the American Academy of Pediatrics. This led to increased availability of fruits, vegetables, whole grains and lower-fat milk for WIC enrollees.

WIC is a federally funded program for low-income pregnant women, new mothers, infants and children under age 5, providing healthy foods and nutrition education and promoting breast-feeding and supporting nursing mothers. It served approximately 6.3 million people in 2018, including nearly half of all infants born in the U.S.

“Improvements in national, state, and caregiver guidance around nutrition and physical activity may be contributing to this decline in childhood obesity,” CDC Director Robert Redfield said in a statement. “We are moving in the right direction.”

Coinciding with this new CDC study, the Robert Wood Johnson Foundation on Thursday released a special report called Obesity Rates Decline Among Young WIC Participants which includes policy recommendations regarding WIC as well as stories about how some are using WIC to help children grow up at a healthy weight.

The CDC data shows that real progress is possible, said Jamie Bussel, a senior program officer at RWJF.

“It reinforces the importance of early intervention and getting kids to a healthy weight by kindergarten,” she said in a phone interview. “Changes made to WIC are having a real impact.”

The government’s other food assistance program, SNAP, has been embroiled in partisan issues in the Trump administration, which has proposed eliminating benefits for more than 3 million people and reducing access to free school meals, which would affect another estimated 600,000 students.

“WIC has retained pretty strong support across the aisle,” Bussel said. “There are gross misperceptions around SNAP and its misuse and abuse. Perhaps moms and young children are seen in a different light.”

In light of the obesity statistics, RWJF is calling on Congress to expand WIC assistance to women for two years after the birth of their baby, and to children up to age 6, to align with participation in school meal programs. The foundation is also advocating for funding the WIC Breast-feeding Peer Counseling Program at its full authorized amount of $90 million.

Bussel noted, however, that overall enrollment in WIC has dwindled in recent years: At its peak in 2010, there were 9.17 million participants; by 2018, that had fallen to 6.87 million. And while 76.9 percent of eligible infants participate in the program, only 26.3 percent of eligible 4-year-olds do.

“We’ve seen a precipitous decline in overall enrollment in WIC,” she said. “There are [erroneous] perceptions around the challenges around recertification and trepidations around immigration issues. There are a host of barriers. Maybe we haven’t done enough around highlighting the benefits.”