I hope you can get the extra food stamps. Keep us posted. I wish I could give you a pile of stuff from our garden. There are some good frugal tips above. Many more are available. Looks like you need to use the highest value basics so you get more calories overall. Well, that's what I would do. I would hate to be hungry and losing weight!!! Potatoes are about the cheapest source of calories. Also canola oil. Do you like potatoes? Do you know how to cook beans from scratch (dry beans)? Do you have transportation to go to a store with best prices? Walmart has the best deals on dried black beans, chick peas, kidney beans and all that, where I am.
If it were me, I'd consider dumpster diving, though I know a lot of places have made their dumpsters inaccessible, as dumpster diving for expensive high quality food was a thing a few years ago.
Best Dumpster Diving Denver 2010 - Between S. Broadway and Acoma St., south of Evans - Westword