How much food is minimum to feed a person? We could supply this

Here This tangential to the article attached. Gwyneth Paltrow is trying to live on 'food stamps,' or really the equivalent which is like $29 dollars a day. Lots or criticism of course, but does create more conversation about this. (1) It looks every hard and sad, especially with children to feed on this amount too! Heartless that people want to reduce food stamp allotments. In our wealthy country supporting billion dollar wars it is unconscionable that a modern country would let a sizable population of it's own citizens starve or nearly starve so we could make bigger tax cuts for the wealthy, etc. (2) How much food is necessary for each person, protein and carbs and hopefully some vegetables and even sugar? I'm sure this is available on the web, and my instinct is that we could supply this for the population of hungry on the planet, by re-prioritizing expenses etc.