This is a small excerpt from a new guide to protein on PEERtrainer. This section helps to shed light on an interesting subject. So often we hear that vegetables are not a complete protein. Here is what that really means:
"One concept always brought up when debating animal versus plant protein is the completeness of the protein. Animal proteins offer a complete array of the amino acids our body needs, and has always been set as the golden standard of protein completeness. Vegetable proteins, on the other hand, are derided as being "incomplete", or lacking in certain essential amino acids. This is true, but in a limited sense.
In reality, the only commonly lacking amino acid in plant-based protein sources is lysine, and plant-based proteins are only lower in it, not completely devoid of it. The amount of lysine considered necessary is a highly debated topic. Low estimates put it at 12 mg/kg, or 870 mg a day for a 160lb. adult, whereas high "safe level" estimates place it at 60 mg/kg, or 4350 mg a day. The estimated amount of lysine the average American consumes in a day is 7600 mg, which is 175% more than the amount even the highest recommendations place."
The article goes on to say that different vegetables have different amounts of lysine. Some of these vegetables have close to the amounts in animal protein!!
Examples given are " legumes, spinach, quinoa and amaranth, pistachios, pumpkin seeds, apples, potatoes, and pineapples.