In a recent online exchange, a poster commented on how extraordinary it was that poor people in our society are fatter than not-poor people. I am not sure the claim is literally true, but I believe it is true that obesity in the U.S. is at least as common among the poor as in the general population, and perhaps more common.
Someone responded that the reason was that more nutritious food was more expensive. She did not go into details, but my guess is that she was thinking of fast food—I have seen other people make the argument in that form. I responded by offering home made bread and lentils as examples of inexpensive but nutritious foods. Another poster responded to that with the claim that home made bread, while tasty and nutritious, was more expensive than "the cheap and nasty supermarket bread."
So I did some price comparisons, getting my price and nutrition information off the web.
Flour, the main ingredient in home made bread, costs about $.50/lb and has about 2000 calories/lb, so about $.25/1000 calories.
Wonder Bread, the classic example of supermarket bread, has 1100 calories/loaf and cost $1.99/loaf on sale at Walgreens, normally more. So about $1.80/1000 calories, or seven times as expensive.
Comparing lentils to fast food, 1 kilo of lentils has about 3500 calories and costs a little over $2. So about $.60/1000 calories
A McDonalds Quarter Pounder with cheese has 520 calories and costs $3.10. So about $6.00/1000 calories. For that comparison, fast food costs about ten times as much per calorie.
Not only are the claims wrong, both are wrong by close to an order of magnitude.
I should add that I bake bread, as does my wife. My version is a sourdough bread, so does not require yeast. The only ingredients are flour, water, sourdough, salt, and raisins, so if I did a non-raisin version the only significant cost would be the flour. It does require an oven, but most Americans, including most poor Americans, have access to one.
My recipe does require some time, although not a lot--perhaps half an hour per pound of flour, counting only time spent actually doing things, not time waiting for bread to rise or bake. But there is a very low work recipe I sometimes use for a yeast bread, based on the recipes in Artisan Bread in Five Minutes a Day, that takes substantially less time than that.