Lesson 6
Protein and the Missing Part
Explain why the scarcest essential amino acid limits what your body builds, and how plant proteins cover each other across a day.
Builds on
Your proteins, built from food’s parts
Protein isn’t only for people at the gym. Every cell in your body is built and run by proteins, and they are constantly being broken down and replaced.
You don’t absorb the proteins in your food as they are. Digestion takes them apart into their building blocks, amino acids, and your body reassembles those into its own proteins. About 20 kinds of amino acid are common in food. Your body can make some of them itself, but for adults nine are essential: they have to come from what you eat.