Protein in the diet:

Protein in the diet is one of the primary nutrients in the food we eat. The main source of protein is from foods such as meat, fish, poultry, eggs, dairy products, beans and nuts as well as from a variety of grains, legumes, nuts, and seeds.

What is protein?

Proteins are the nutrients that provide the "building material" for the growth and repair of tissue and are a key part of every cell in the body.

The word "protein" comes from a Greek root word that means "prime or chief, first." So that gives us a good idea of the importance of protein in the diet!

What is an amino acid?

Proteins break down into substances called amino acids. Amino acids are the building blocks of proteins. There are 20 amino acids that the human body needs to function.

There are two groups of amino acids - "essential amino acids" and "non-essential amino acids."

• Essential amino acids are called "essential" because your body can't make them. They need to be obtained from protein in the diet. There are 9 essential amino acids.
  
• Non-essential amino acids are called "non-essential" because it's not essential that you get them from the protein in food - your body is able to manufacture them from material that's in your body. There are 11 amino acids that the body can make with the material it has.

"Complete" proteins are found in animal protein such as meat, fish, milk, and eggs. The soybean is also a source of complete protein.

Protein from plant sources, like corn and rice for example, is "incomplete" - simply meaning that it doesn't have all 9 essential amino acids. This doesn't mean that plant protein is inferior by any means! "Complete" and "incomplete" proteins merely refer to the number of essential amino acids in them.

Amino acid function

Amino acids, the building blocks of protein, are restructured in the body to create:

Hormones:

Hormones are proteins that are produced by living cells. Hormones circulate in body fluids, such as the blood, and cause a certain effect on other cells that are usually at a distance from the place where the hormone is made.

For example: Adrenalin is a hormone that is produced by the body in times of stress and adrenalin causes the heart rate and breathing to speed up.

Enzymes:

Enzymes are complex proteins formed by plant and animal cells that assist or enable chemical reactions in the body to occur.

Digestive enzymes, for example, help your body break food down into chemical particles that can be absorbed into the bloodstream.

Antibodies:

An antibody is a protein produced by certain white blood cells in response to a foreign substance, called an antigen, such as bacteria.

Hormones, enzymes and antibodies are just a few of the things that are ultimately made by the body from the protein in the diet.

Daily Protein Requirements

The amount of protein you need every day depends on various factors, including gender, age and level of physical activity, but is roughly about 20% of your daily nutritional needs.

Here is an excellent article about healthy protein consumption from one of my favorite sources of health information, Dr. Ben Kim: "Fuel Your Best Health with Healthy Protein." He writes like you're having a conversation with him too.

Protein is seldom used for energy. That's the job of carbohydrates and fats.

Okay! Hopefully this overview has helped you better understand the importance of protein in the diet.

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