The USDA has just cobbled together a ton of data on access to food around the U.S. (sadly hosted on some of the worst, slowest servers on earth). One of the tools it has created is an interactive map of "food deserts," which it defines as: "a low-income census tract where a substantial number or share of residents has low access to a supermarket or large grocery store."
The data identifies nine food deserts in Multnomah County, in which a total of 17,537 residents have low access to a supermarket or large grocery store, of which 6,850 are classified as "low income," 4,708 are under 18, and 1,837 are over 65.
The worst affected area appears to be around Glenfair Park, where 100 percent of residents have low access, almost a third of whom are children.
The Department has also created a "Food Environment Atlas," mapping things like communities' proximity to farmers markets, restaurants, prices and relative health indicators.
According to the data, Multnomah County purchases 49 gallons of soda, 109 lbs. of packaged sweets and snacks, and 56.7 lbs. of fruit and vegetables per resident, per year. We spend an average of $710.69 per person, per year at fast-food outlets, and $778.44 on full-service restaurants. As of 2008, we have 1,026 fast-food outlets, and 646 full-service restaurants.
There's just so much graph pr0n here, you should go play with it yourself (if the site is actually working).