I'm looking at one of your citations now, and it lumps all households below about $20k into the 'poor' bracket.
That's actually very likely the right thing to do. Thanks to various wealth transfer programs, anyone with earned income <$20k has consumption of approximately $20k.
Calories are not nutrition. Food loaded with sugar and preservatives is much cheaper than healthy foods, and it also happens to be more readily available. Many poor neighborhoods don't have grocery stores where one can purchase fresh fruit and vegetables, but they do have convenience stores where you can buy all the candybars and junk food you can eat... at a considerable markup.
If someone gets fat off potatoes and bread they are consuming too much. They could reduce consumption of potatoes/bread and spend the money they save on vegetables.
That's actually very likely the right thing to do. Thanks to various wealth transfer programs, anyone with earned income <$20k has consumption of approximately $20k.
ftp://ftp.bls.gov/pub/special.requests/ce/standard/2009/income.txt
We don't need to see people literally starving to death to accept that people have a problem getting enough food.
Are people even becoming slightly less fat? That will happen long before anyone starves.