Proteins can be found in any animal based product and some plant based products too, we are made up of proteins, from our skin and hair, to our beating hearts. Defined from a nutritional point, they are structures of molecules that are made from Amino Acids, which are linked together through peptide bonds. There are over 500 known Amino Acids and so combinations of proteins are varied and abundant, common examples will include Meat, Eggs, Milk, Soy and Nuts and Fruits.
Proteins are essential to the body, they help repair muscles and are key for the growth of young children. You will often see Body-Builders eating protein bars or meals with a large amount of red meat, this is to provide the body with essential chemicals in repairing torn muscle. Not everyone should be eating proteins in such high amounts though, as many people do not do the necessary amount of exercise to warrant such an abundance.
In nutrition, proteins are then segmented into three categories for the body; Essential, Non-Essential and Conditional.
- Essential - The Essential proteins are the Amino Acids that cannot be produced by the body, these are the ones that we must get from food sources, they have to be consumed so the body can them process them.
- Non-Essential - This leads on to Non-essential proteins or the Amino Acids that are made by our bodies, they are a by-product of the proteins we have eaten.
- Conditional - Finally there Conditional Proteins or Amino Acids, these are the chemicals that the body only requires when repairing itself or if the body has an illness, they can be found in specific foods or if a person suffers from a life-long medical condition they will obtain them from supplements.
Though proteins are used in the repair of the body, they do not make the best sources of energy, this is often taken on by carbohydrates and the job of proteins is served elsewhere. Proteins in the body, are used as enzymes that deal with metabolism, DNA replication, muscle repair and about 4'000 other known reactions.
An excess of proteins, like any other food group can be harmful to the body. The digested proteins become Amino acids and travel through the blood stream of the body, when the body expels the excess chemical through urination, the amino acids must pass through the Kidney. While the kidney is evolved to deal with an excess amount of amino acids, it can lead Kidney stones over a long period.
Due to the variety of structures that amino acids can take, some bodies can process certain proteins and others can not, causing allergic reactions, common examples include; Milk, Peanuts and Shellfish.
Just like any other kind of food, the quality of proteins can vary greatly, through breeding to raising, how the food is developed goes a long way to what you are eating.