What is the reason behind decline in Obesity rate to 43 percent in US children?

At the time when Americans are struggling from obesity, statics has revealed that this rate is declining among US preschoolers by nearly half in some near years. Only eight percent of total children aged from two to five were obese in the year 2011-2012. the CDC's Tom Friedan has mentioned "We continue to see signs that, for some children in this country, the scales are tipping," He has further highlighted that this revision comes on the heels of at large CDC data showing a " This significant decline" in the rate of obesity is noted in low-income families and children having age group of two to four are now participating in this federal based nutrition programs. He had further added that "This confirms that, at least for kids, we can turn the tide and begin to reverse the obesity epidemic" The most precise reasons for this drop are still not much clear.