The reason MRE's are light weight is because they don't have water. But it's a false economy, because you need that water anyway. And, well, they're darn expensive.

You can do pretty much the same thing simply by drying foods at home, and carrying them in airtight containers. Beef jerky is lightweight and nutritious.

Personally,I stock up on Dinty Moore Beef Stew or other canned stews, and canned fruits. Obviously they're heavier, but that means there's that much less water you will have to carry. And they're a whole lot cheaper and tastier than those dumb MRE's.

Onward and upward,
airforce