I have mentioned this on Medium before but one year my parents decided to cut out all prepackaged or processed foods from our diet. We bought flour in bulk and baked all of our own bread. We dug up the back yard and grew vegetables and canned our own tomatoes. My mother kept meticulous records and at the end of the year we had spent about $60 less for a family of six than what the US Government considered poverty level spending for a family of four.