BuT vEgAnS cAnT bUIlD MuScLe, mAyBE LEnTiLs hAvE tOo mUcH prOtEin
Legumes tend to be very filling for the amount of protein they provide, plus having to complement them with grains to make a complete protein greatly increases the Calories to protein ratio. Rice and beans do make for a great cheat meal when you can fit it in though.
I’ve never heard of needing to add grains to make a complete protein. What does that even mean?
Proteins are made from amino acids, same as words are made from letters. If you eat a protein source that’s short on some of those letters then you need to mix it with a source that has more of them… Otherwise you can’t create all the proteins that you need. (It’s a bit more complicated, but that’s the bit that you need here)
You didn’t really need to, if you are not in a heavily restricted diet. Adam Ragusea has a nice video about this: https://youtu.be/psAlJtgeQsY
They can, but it takes a large amount more work to balance for complete amino acid profiles in the diet.
Meat and eggs are “complete” proteins, which contain all the aminos you need to build muscle. Plant proteins are “incomplete” proteins, which means the amino profile is not complete and missing some amino acids.
It’s not insurmountable, but some planning is needed to fill in amino gaps in one incomplete protein source with a complementary protein source. Example would be rice and beans tend to be complementary.
Your post contains a lot of incorrect information. First of all, basically all plant proteins contain every essential amino acid. You can nitpick about certain foods being low in certain amino acids but void of them they are not which is what you are claiming. But also your statement on complementary foods is incorrect. Legumes and most vegetables don’t need to be complemented by anything. Certain grains like wheat are lacking, but quinoa is fine. Potatoes are lacking, but squashes are fine. Basically all fruits are lacking and just low in protein overall. “Don’t eat a diet of fruit and bread.” is a pretty big step from “It takes a large amount more work…”
And this is tangential but we should be concerned about nutritional content in general, not simply the amino acid profile. Amino acids are simply just some of the many essential things our bodies need. Compared to vegetables like spinach, steak and eggs are by far more nutritionally incomplete.