I thing the US MRE's are a lot better than the 7 day ratpacks we had.
Think of a small cardboard box about the size of a half loaf of bread, containing all the food you would need for a week. 1 small pack of tea, sugar packs and condensed milk. One small can of the following, corned beef, anchovied in hot sauce, beans, maize kernels, spaghetti in tomato. Also a pack of things that could be called biscuits, but which could also serve as lethal weapons in an emergency. A small pack of boiled sweets. A pack of fuel tabs to use to heat the lot and a box of unlabelled matches. you needed the standard things you has as issue, a set of cutlery ( still have mine), a water bottle and a camping fold out plate cum cooker along with a folding spade. That was to last 7 days. Not included was water purification tablets, which really should have been included. Also not included was the white gold, and meant you got really good at finding suitable leaves that did not cause any itching when used.