Part of the Get Healthy Philly initiative involves getting rid of so-called “food deserts” (large areas with inadequate access to affordable healthy food options) and giving low-income communities more access to fresh fruits and vegetables in hopes of reversing the city’s obesity epidemic.

This idea—based upon the assumption that access to healthy food means buying healthy foods—is being closely monitored by the Obama Administration and if it works, could be seen as a national model to fight obesity in cities all over the country.

Ezra Klein at the Washington Post has a good write-up today of what Philly’s food desert destruction could mean for national food policy. If successful. It’s the latest in a series of attempts to interfere in the free food market and change spending habits. Klein notes that the Journal Obesity Review found in 2011 that “greater accessibility to supermarkets or less access to takeaway outlets were associated with a lower prevalence of obesity”—but what’s unknown is whether new access will equate to new purchases, and if it’ll be enough to keep shops in business due to the shelf life of candy vs. vegetables in small stores.

A study done in the U.K. found that eating habits barely changed during one case of food desert intervention in 2002. A similar study conducted in Chicago, Birmingham, Minneapolis and Oakland found “no connection between a new grocery store and better health outcomes.”

The Philadelphia program seeks to create more GreenGrocers, as these healthy corner stores are called. The city has often provided these stores with free stuff, including refrigerators, if they agree to participate. Additionally, Temple University’s Center for Obesity Research is conducting a study with the city to see “how shopping habits do, or don’t, change when healthy options are introduced,” by, if you’ll believe it, actually stopping people leaving healthy corner stores to see what they bought. And if it works this time, Philly could be a national model for the Obama Administration’s food policy.

Nationally speaking, Nutter has been at the forefront of the obesity fight. Even if it’s so far proven unsuccessful. In addition to his anti-soda agenda, which includes his push for a soda tax and approving signs discouraging soda purchases outside corner stores, Nutter’s championed anti-smoking legislation, first as a councilman then as mayor. The city got $25.4 million in stimulus funds to fight obesity and tobacco use and $17 million more in a TIGER Grant to build bike lanes and create other access for bicycles. Yesterday, speaking at the National Sugary Drinks summit, Nutter called New York City Mayor Michael Bloomberg’s plan to ban super sized sodas “worth evaluating and considering.” This is in spite of hard lobbying efforts from the American Beverage Association in Philadelphia.

Nutter seems to believe this “all of the above” approach is the ticket. Whether it is or not, one thing’s for sure: Something needs to be done. Philly is now the fattest, poorest big city in the U.S.