Important of Protein in our diet

In our food components proteins are essential nutrients for the human body.  As a fuel, proteins provide as much energy density as carbohydrates: 4 kcal per gram; in contrast, lipids provide 9 kcal per gram.

Proteins are the building blocks of life. Every cell in the human body contains protein. The basic structure of protein is a chain of amino acids.

We need protein in our diet to help our body repair cells and make new ones. Protein is also important for growth and development in children, teens, and pregnant women.

There are 20 different amino acids in total, and the sequence of amino acids determines a protein's structure and function. While some amino acids can be synthesized in the body, there are 9 amino acids that humans can only obtain from dietary sources (insufficient amounts of which may sometime result in death), termed essential amino acids. Foods that provide all of the essential amino acids are called complete protein sources, and include both animal (meat, dairy, eggs, fish) as well as plant-based sources (soy, quinoa, buckwheat).

Proteins can be categorized based on the function they provide to the body. Below is a list of some types of proteins:

• Antibody :- Proteins that protect the body from foreign particles, such as viruses and bacteria, by binding to them
• Enzyme :- Proteins that help form new molecules as well as perform the many chemical reactions that occur throughout the body
• Messenger :- Proteins that transmit signals throughout the body to maintain body processes
• Structural component :Proteins that act as building blocks for cells that ultimately allow the body to move
• Transport/storage :-Proteins that move molecules throughout the body

·         Recommended dietary allowance (RDA) of protein, based on age

	Protein Needed (grams/day)
Age 1 - 3	13
Age 4 - 8	19
Age 9 - 13	34
Age 14 - 18 (Girls)	46
Age 14 - 18 (Boys)	52
Age 19 - 70+ (Women)	46
Age 19 - 70+ (Men)	56

Adults should eat at least 0.8g of protein per kilogram (2.2lb) of body weight per day. That means a 180lb man should eat at least 65 grams of high-quality protein per day. A higher intake may help to lower your risk for obesity, osteoporosis, type 2 diabetes, and stroke.

• Nursing women need about 20 grams more of high-quality protein a day than they did before pregnancy to support milk production.
• Older adults should aim for 1 to 1.5 grams of protein for each kilogram of weight (think 0.5g of protein per lb. of body weight if that’s easier).
• Try to divide your protein intake equally among meals.

Source: Environmental Nutrition

Amount of protein in common food

	Protein Amount
Milk (1 cup/8 oz)	8 g
Egg (1 large/50 g)	6 g
Meat (1 slice / 2 oz)	14 g
Seafood (2 oz)	16 g
Bread (1 slice/64 g)	8 g
Corn (1 cup/166 g)	16 g
Rice (1 cup/195 g)	5 g
Dry Bean (1 cup/92 g)	16 g
Nuts (1 cup/92 g)	20 g
Fruits and Vegetables (1 cup)	0-1 g
Pizza (1 slice/107 g)	12 g
Hamburger (McDonald Medium)	20 g