What are proteins and amino acids?

Protein is a macronutrient that is used mainly as a building block in the body, but it can also be broken down into energy when there’s a lack of carbohydrates and in some cases fat.

Proteins are made up by chains of amino acids that have various important functions in the body.

They act as building blocks in various tissues around the body, it is used in communication between nerve cells in, as building blocks in our immune system and much more.

Some examples of tissues and structures that are made up by protein in the body are: 

• muscles 
• bones (did you know that the sceleton is actually made up by a protein structure called matrix that is mineralized to harden?)
• skin (for example collagen, keratin and elastin)
• hair and nails
• enzymes (read about enzymes here)
• neurotransmitters (for example seritonin, dopamin)
• hormones (for example insulin)
• antibodies 
• transport (for example lipoproteins that transport cholesterol)
• energy (provide 4 kcal per gram protein) 

What are amino acids?

Humans need 20 different amino acids. 9 of these amino acids are so called essential. That means that we have to get them from the diet because we cannot make them in the body.

When we eat foods or supplements that contain protein the proteins are first broken down into single amino acids that are taken up in the gut. The amino acids are used to build new protein in the body.

So when you eat collagen rich foods, the collagen will be broken down to single amino acids used for building protein in the body. Then new collagen is formed where there is a need. It is important to add the right amino acids and other nutrients for new collagen to be formed.

They may be used for building different kinds of protein or for collagen somewhere else in the body, ligaments or bones, for example. But by providing the building blocks for collagen, you increase the likelihood of forming collagen in your skin.

What is a complete protein?

A complete protein is a protein that contains all the essential amino acids. Animal proteins, such as meat, poultry, fish, eggs and dairy contains complete protein in good amounts.

Some vegetable protein contains all essential amino acids and are therefore classified as complete protein, for example soy, quinoa and spirulina.

Vegetable sources of protein are beans, peas, lentils, mushrooms, grains and vegetables. These vegetable protein sources don’t contain the essential amino acids in sufficient quantities, so they need to be combined with each other in order to provide the whole range of essential amino acids.

Therefore vegans and vegetarians need to pay attention to how they eat and combine different sources of protein, to ensure that they get all the essential amino acids.
 

Good quality protein

In protein from meat, the amino acids are composed in such a way that it suits the needs of our bodies, you could say that the composition is more similar to our bodies, than the composition of amino acids is in protein from vegetable sources.

As well as being a complete protein, animal protein is therefore also considered a good quality protein. This means how well the composition of the amino acids suits the human body’s needs.