First lady Michelle Obama gestures while speaking speaks at the National League of Cities Conference about the Let's Move! initiative in Washington March 15, 2011. (Uncredited/AP)

The campaign against childhood obesity that has become Michelle Obama’s signature program will ramp up again this week as she begins a three-state tour focused on boosting physical activity and healthy eating.

The Let’s Move initiative, which Obama has made nearly ubiquitous, has served to elevate the issue of children’s health and fitness. As the program enters its third year, questions remain about whether the efforts the first lady has backed will be long-lasting.

Still, Obama plans to continue to energetically push and expand the initiative. Doing that means spotlighting places she sees as gaining ground, something the first lady intends to do Wednesday in Clinton, Miss., at the start of her Let’s Move tour.

Mississippi’s childhood obesity rate is down 13 percent to 38 percent. The state remains among the most obese in the nation, according to the Centers for Disease Control and Prevention, but a new report shows that its rate of childhood obesity has dipped below that of California. Mississippi officials attribute the drop to a local focus on the issue, a 2007 law that mandated more physical education and a decision by the state school board to put more fruits, vegetables and whole grain on menus.

“There is no reason why this success can’t happen in cities and states all across this country, if we’re willing to work for it,” Obama plans to say, according to excerpts of her remarks released by her office. “Now is truly the time to double down on our efforts. We know what works. We know how to get results.”

Obama, who pushed for the passage of federal legislation requiring healthier school lunches, also plans to applaud the changes made by cafeteria workers, who will be on hand.

The revamped school meals have not been without controversy. A few videos of students protesting the lower-calorie menus gained traction online last year. Recently, the Agriculture Department decided to extend a window of flexibility to schools that were having trouble meeting the strictest nutritional standards.

The White House remains undaunted.

“Most simply put, there are two basic things we need to do: We need to help make the healthiest choice the easiest choice for families,” said White House assistant chef Sam Kass, and give them “real, actionable information to help them make better choices.”

To that end, Obama has been asking corporations to open stores that sell fresh food in areas where grocers aren’t easily accessible, and she has pledged to eliminate such “food deserts” — the USDA has identified more than 6,000 of them — by 2017. However, studies of whether access to healthy foods improves nutrition have been inconclusive.

Still, many who have been pushing for a focus on these issues see Obama as an amplifier. Chef and TV host Rachael Ray will film her talk show at the first lady’s event in Mississippi.

“No matter which side of the aisle you’re on, every adult American should be thinking about child nutrition,” Ray said. “Our kids are suffering in a very real and alarming way from adult disease at alarming rates.”

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