Protein plays an important role in your diet. Our body needs protein as it is a major part of the skin, muscles, organs and glands. This is why your mother plans your diet to ensure you have a lot of protein in it.
What is a protein?
A protein molecule is made up of amino acids. Just like you can make amazing things out of Lego blocks, amino acids are your body’s building blocks. Out of 22 amino acids, 8 of them are essential as they are not produced in our body.
The main sources of protein are egg whites, meat, fish and some dairy products, however even grains like wheat and vegetables provide us with protein.
Types of proteins
There are two main classes of proteins - globular and fibrous proteins.
Globular proteins: As the name suggests, these are three-dimensional spherical or globe shaped cells. These ball-like proteins react with alkalis and acids. They dissolve to form a colloid solution, a solution in which a substance is evenly spread throughout another.
Globular proteins usually change faster than fibrous proteins and play a variety of roles. These proteins can act as enzymes by speeding up reactions which take place in the organism. They transfer messages acting like your own biological telephone in your body; sending messages to regulate biological and metabolic functions. These are strict little proteins, performing all the regulatory roles in the body as well.
Fibrous Proteins: These cells are long rod-like or wire-shaped. Fibrous proteins do not dissolve in water and resist alkalis and acids. These proteins cross-link with each other to form long wire-like fibres. They play a protective and structural role in the functioning of the body. They usually make connective tissues, muscle fibre and tendons. For example, collagen which is a connective tissue in the body and keratin which makes up our hair and the outer layer of our skin are all formed from fibrous proteins.
Different protein structures and their functions:
The structure a protein has will determine what role it has to play in your body.
Antibodies: The proteins that are important for protecting the body from various antigens. They help keep you healthy.
Enzymes: The proteins that control and help all the biochemical reactions which take place in the body, for example pepsin.
Hormonal Proteins: Help control and co-ordinate all the bodily activities of the body; they are messenger proteins like insulin.
Storage protein: Like ovalbumin, the protein found in egg whites, stores amino acids in the body.
Carrier proteins: These transport molecules around the body. Their role includes the transfer of oxygen through the blood and haemoglobin.
Contractile Proteins: Like actin and myosin, these proteins are responsible for all the movement which causes muscle contraction and skeletal muscle.
Proteins as a nutrient
As the building blocks of the body, protein helps muscle growth in the body. They keep our immune system healthy; create hormones and a lot more.
The main sources of protein are egg whites, meat, fish and some dairy products, however even grains like wheat and vegetables provide us with protein. Other sources include lima beans, soybean, barley, brown rice, cabbage, cauliflower, cucumbers, green peas, mushrooms, onions, potatoes, spinach, tomato. Fruits that are rich in protein include apple, banana, grape, orange, papaya, pears and pineapples.
The importance of protein in your diet
If you don’t have enough protein you might become ill. In developing countries many people die because of lack of protein. Lack of proteins in your diet is one of the main causes of the disease kwashiorkor which can cause edema, anorexia, irritability and an enlarged liver. Also patients having certain medical conditions like gout are advised not to have too much protein in their diet.