Many poor people live in food deserts so don’t have access to decent quality food. If you have poor public transportation and have to walk to a convenience store to get food it’s going to be more expensive and unhealthy.
I hear this a lot, but I'm not entirely convinced that "food deserts" really exist within urban areas.
In some of the more poor-concentrated parts of my own home town, I don't know of any place that is more than a mile from a Walmart, 99c Only, Winco, or Grocery Outlet; all of which sell milk, vegetables, fruit, bread, and so on. I'm not saying this is universally true, but I don't think that food deserts are really part of the nutrition problem.
The arguments I usually get from this observation are usually the following:
1) Discount stores?! Eww!! You must really hate poor people to suggest that they eat food from there.
2) Yes, but there are twice the number of Taco Bells and Liquor Stores in the same area
3) But my kids won't eat vegetables
4) Working two jobs, I don't have time to cook it
5) Discount stores are contributing to the problem with their low wages
6) Discount stores are making urban problems worse by driving out higher-quality stores.
I'm not suggesting that you make any of these arguments, just that I hear them a lot. As for #1, I can only say that the real contempt for the poor is in the attitude that poverty is defined by the inability to eat premium quality ingredients, or shop at swanky stores. For what it's worth, I and my mustache shop almost exclusively at the grocery stores mentioned above.
As for #6: to the extent this is true, I say, good. It is unacceptable that the choice is between premium food or no food, and a free market does exactly what it should: presents an alternative. Likewise, #5 is actually a solution to a problem: the choice between high wages or no wages.
The rest of it, I actually agree that it's all a problem. It's just not a problem of food availability. There is a lack of transportation, a lack of life skills, a lack of nutrition education, a lack of planning, and so on. To approach these as a problem of food availability is to whiff these problems entirely, and suggest a solution that cannot be successful.
Then again, I don't really spend much time on the mean streets, so I may have it wrong. There may be food deserts. I just haven't had one specifically pointed out to me.