Protein is a major building block of the body’s tissues and organs, including skin, muscles and hair. It also helps the body maintain and repair itself, as well as grow. Protein is not the body’s first choice for energy, however if it runs out of carbohydrates and fats it will use protein for energy.
Proteins are made of building blocks called amino acids. There are 20 different amino acids, each with a unique chemical property. Amino acids are arranged in chains of hundreds or thousands of amino acid “letters” to form proteins. The specific number and order of amino acids in a protein determines its function.
The amino acid “letters” in a protein are bonded together using peptide bonds to create proteins with four general types of structure: globular, fibrous, linear and elongated. Each type of protein has a different function. For example, the iron-containing protein hemoglobin is a globular, soluble protein that is compact and spherical.
Our bodies can make 11 of the 20 amino acids that form proteins, but we need to get nine of them from food. These are known as essential amino acids, and foods such as meat, fish, poultry, dairy products, eggs, nuts and beans contain these amino acids. Proteins found in animals are often referred to as complete proteins because they contain all of the essential amino acids, while plant-based proteins are typically incomplete. Protein is the most important nutrient for muscle growth and development, but it also helps our cells and tissues stay healthy and strong. It carries oxygen into our blood and tissue cells, and it helps heal wounds. Protein also helps our bones stay strong and prevents them from breaking as we age, and it keeps us from losing too much weight by helping to build and preserve lean muscle.direct peptides