Proteins exist in all the organisms. The cells need proteins to carry out all its functions. Amino acids form these proteins which are organic compounds. The process of formation of protein is carried out in the stomach when food is broken down and digested. The metabolic activity in the body requires proteins. Calories, which we know as the energy, are produced from protein, fat and carbohydrates from the food that we take. Dairy products in various forms including cheese and milk, eggs, nuts, legumes and meat are the main source of proteins.  The food particles are broken down in the stomach continuously from which proteins are derived. The proteins are broken down through digestion by enzymes. The estimated requirement of protein of women are said to be lesser than men. While the men require 56 grams of protein per day, the women require 46 grams of protein per day. When the intake of protein is lower than the required intake, protein deficiency sets in.

Protein deficiency can be the cause of ill health and even death. Kwashiorkor with such symptoms as diarrhea, inactivity, apathy, failure to grow, fatty liver, flaky skin, and edema of the belly and legs is caused by chronic protein deficiency. Protein deficiency can also cause mental retardation. It usually afflicts poor people everywhere as they face nutritional deficiency or chronic hunger. Protein deficiency is known to also occur amongst those who are crash dieting or dieting in order to lose weight. Sometimes older people too have protein deficiency when their diet is not balanced. This could also be the case with people convalescing from illness, trauma or surgery. High protein diet or protein rich food is required in these instances to provide the required protein.

There are a variety of dietary supplements in the market containing carbohydrates, proteins, fats, minerals and vitamins. The source of protein is often soy, casein or whey. Flavors are added to make them tasty. These dietary supplements are available as energy drinks or energy bars. Energy bars offering primarily proteins are also available. Pure Protein Bars are also available in the market. These have more protein than other ingredients. Protein bars come in a variety of mouth watering flavors.

Such supplements give both calories and proteins. Pure protein enters into the body to offset the deficiency.