1. Protein is an essential component of the diet and helps your body repair muscle, grow tissue, regulate hormones, control metabolism, defend against illness, and more.
Protein is what makes up your ligaments, tendons, muscles, hair, nails, skin, teeth, tissue, organs, and bones. About half of the non-water mass of your body is made up of protein.
Since most of the body's proteins are continually broken down, the body needs to manufacture thousands of proteins every day to replace them. The more active you are the faster your proteins break down, and more protein you need to replenish them
  
2.Protein consists of smaller units of amino acids. These amino acids, formed of carbon, nitrogen, hydrogen, and oxygen atoms, are literally the building blocks of the human body. From these amino acids, your body can make hundreds of different proteins that perform different functions.
On its own, the body can manufacture 14 of the 22 amino acids it needs. But the other 8 cannot be made by the body and must be obtained from the diet. In order for protein synthesis to take place, all 8 of the essential amino acids must be present. All 8 must be at the cell at the same time; otherwise protein cannot be made. These eight amino acids are called "essential amino acids" and include:

• Isoleucine
• Leucine
• Lysine
• Methionine
• Phenylalanine
• Threonine
• Tryptophan
• Valine

The body uses the amino acids obtained from dietary protein or amino acid supplements to build the body's proteins, which become the structural foundation of the body.

3. Daily protein/amino acid intake is required to maintain or normalize cellular turnover and optimize the body's protein synthesis. Without sufficient protein, the body either lets cells die or breaks down other muscles and tissues to get the protein it needs for repair and other functions.
The body may actually "eat itself" to acquire the necessary amino acids, or borrow the amino acids from the immune system or body functions to meet its protein needs.

4. Seafood is an excellent source of protein and is rich in omega-3 fatty acids. The consumption of  seafood has been linked to a reduced risk of many diseases. Seafood is low in caloric content and also has less saturated fat and cholesterol than meat that comes from land. For example in a 4 oz. piece of salmon our %DV in

   • Tryptophan    103.1%                                                                            
   • Omega-3 Fatty Acids   83.6%
   • Protein   58.3%
   • B3   56.7
   • B12   54.2
   • B6   26 %

The consumption of Omega-3's and protein reduce the risk of many diseases.

5. Legumes a another excellent source of  protein, vitamins, minerals and Phytonutrients. They are a great substitute for meat. You get the protein and nutrients while avoiding saturated fat and cholesterol. This means you will avoid putting on extra unnecessary weight. They also have more protein (amino acids) than any other type of plant. Soybeans are a good example of this. For a one cup serving they contain a high level of the amino acids, B vitamins 1,2,3, and 6, and minerals such as copper, iron, magnesium, phosphorus, and zinc. Soybeans promote heart health.