You may have heard the terms “complete” or “incomplete” protein before.  Today we’ll describe exactly what each one is, and why it matters.

Protein is necessary for just about everything that goes on in the human body.  Protein builds the structure for more than just muscles; it provides the walls for bones, internal organs, hair- everything!  Proteins also serve as important messengers that start, stop, speed up, or slow down every reaction in the body.  Because we use protein so much, we have to eat protein every day to replace what we use up.

Proteins are built out of smaller structures called amino acids.  Our body can sometimes make amino acids out of other things, but there are nine essential amino acids that we have to get from food every day.  Plant protein and animal protein differ in their amino acid content:

Animal Proteins like meat and dairy contain all nine essential amino acids, so they are considered complete.

Plant proteins like beans and nuts are lacking some amino acids, so they are considered incomplete.


Why does is matter?  Because if your body is missing an amino acid it needs, it will stop whatever activity it needs it for.  My husband is an organic chemist, and he compares reactions like this to sandwich making.  In order for your sandwich (reaction) to get made, you need both cheese (one reactant) and bread (other reactant).  If you still have cheese but you run out of bread, the sandwich making process stops (and we all go hungry).

So what do you do if your meal only has plant proteins?  You can combine multiple proteins and they will complete each other.  In order to get a complete vegetarian protein you can combine:
  • Beans and Grains
  • Beans and Seeds
  • Beans and nuts

If you eat dairy you could also combine that with any one of the foods above to make it complete.  There are two vegan proteins that are complete: soy and quinoa.  Soy is a bean that can be eaten on its own or in the form of tofu, tempeh, or natto.  Quinoa is treated as a grain but is actually a seed.  It is cooked like rice and can be served just about any way you’d like.



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