Protein: What Is It? Where Do I Find It?

Many of us know we need protein, but don’t have a clear idea of what it is, why we need it, or even where it comes from! Read more, and we will demystify this molecule.

What is protein? What is an amino acid?

Here’s some science for you. Protein is a type of molecule found in all living organisms. Each protein molecule is made up of building blocks called “amino acids.” There are 20 different amino acids which all have a unique shape, and when mixed together, form a protein. 

Proteins from different sources are shaped in a specific way, depending on how the amino acids are linked together. just like how Lego blocks come in different shapes and sizes, but all blocks connect together. 

There are 9 essential amino acids that we must get from food. The other 11 amino acids can be synthesized by your body naturally. When the protein molecule is made, the specific shape of it will determine what job it does in the body. 

Think you need an amino acid supplement? You probably don’t, since most proteins you eat will have it. Eat a variety of protein to get a good amino acid balance.

Why is protein important?

Protein is an essential nutrient that we all need in our diets. Your body uses protein to

• Build and repair muscle and other tissues
• Make enzymes
• Make hormones
• Form other essential chemicals and structures for our cells

The average lean human body is made up of about 20% protein and about 65-70% water. So in addition to needing to consume a lot of water, we also need to make sure we get enough protein in our diet each day! 

Protein in the diet

Protein in they diet can be found in a variety of foods, and in fact, exists in nearly all foods. But protein is most rich and most complete for the body in these food types:

• Red meat (beef, pork, and other game meats)
• Poultry (chicken, quail, pheasant, and other birds)
• Eggs
• Fish and shellfish
• Soy (Tofu, soy milk, tempeh, and soybeans)
• Dairy (Milk, cheese, cottage cheese, and yogurt)

But remember, not all proteins are considered a “complete” source of the 9 essential amino acids that your body needs. These are called “incomplete” proteins. To make these incomplete proteins whole and balanced for your body, you should usually combine 2-3 of them together. Here are the 3 main food categories of incomplete proteins:

• Legumes (all beans, peas, and lentils)
• Nuts and seeds (almonds, peanuts, and other nuts, chia, flax, hemp, and other seeds, any peanut butter, almond butter or other butter made from nuts or seeds)
• Whole grains (quinoa, oats, barley, farro, teff, brown or black rice, and whole wheat)

Protein quality matters

Remember that not all proteins are great for you, and even if you are eating some foods containing protein, they may be incomplete by themselves, and not so useable by the body. Here are some things about proteins to keep in mind:

• Animal sources of protein (meat, seafood, eggs and dairy) are the main sources of “complete proteins.” 
• Certain plant proteins can be paired together to become “complete proteins.”
• Plant proteins need to be consumed in larger proportions in order to meet your protein needs.
• Eat a large variety of foods to ensure optimal nutrition.
• Always choose whole, unprocessed foods over-processed foods. Ask your dietitian to help you identify which foods are “processed” vs “whole and natural.

Takeaways

Protein is important for the human body, but knowing how much you really need, getting complete proteins with your meals, and making the protein high quality makes a huge difference. Talk to your Registered Dietitian to learn about how much protein you need for your activity level, clinical conditions and goals. Also try reading our other articles about how to determine a protein serving size, and also how to make a perfect and complete protein from vegetarian sources.