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What Is Protein? Composition, Sources, Protein for Weight Loss

Creative Content Writer keens on researching and outspreading fitness and nutrition facts to make her readers lead a fit and fab life.

What Is Protein?

Protein is known as body-building food, and it helps to maintain life and promote growth. Protein is found in every cell of the human body and formed one-fifth of the adult’s total body weight. All the tissues in your body are made up of protein including, muscles, bone, blood, skin, and hair. Thus without protein, humans are called skeletons.

Important Functions of Protein In Your Body

  • Protein helps in building and repairing body tissue. Protein supports growth and forms integral parts of the skin, tendon, membrane, muscles, bones, and other organs.
  • Protein provides fuel for the body to generate energy.
  • It helps in the formation of enzymes. Lipase helps in the breaking down of fat.
  • It regulates hormones to maintain body processes.
  • It acts as an Antibiotic by inactivating foreign bodies and protecting the body against disease.
  • Protein helps to balance the volume of fluid, acid-base, and electrolytes in the body.
  • It stores iron and copper and transports nutrients to the tissues. For example, hemoglobin transfers oxygen.

Most of us assume iron is enough to fight against anemia, but the fact is iron along with protein is required to increase RBC in your body.

Chemical Composition of Protein

Let’s have a scoop on the chemical composition of protein. Protein is made up of amino acids and consists of carbon, hydrogen, oxygen, and nitrogen. The presence of nitrogen makes it stand out from carbohydrates and fat.

The quality of the protein is determined by the kind and the portion of amino acid present in it. A good quality protein contains all the nine essential amino acids in specified ratios.

Protein Rich Foods

Protein Rich Foods

Protein is divided into three categories based on the presence of amino acids.

Complete Protein

Complete protein consists of all essential amino acids required to promote and maintain normal growth in human beings. It includes the protein derived from animal foods such as Egg, Meat, Poultry, Fish.

Partially Complete Protein

A partially complete protein contains the necessary amount of amino acids to maintain life but fails to promote growth in human beings. It includes plant foods and some grains such as Gliadin in Wheat.

Incomplete Protein

The name itself denotes that it is incapable of meeting the essential requirements. It fails to replace and building new body tissues and cannot support growth in human beings. It includes legumes, whole wheat, seeds, and vegetables.

Here we consider the protein content of Egg, which has all the nine essential amino acids in the correct proportion that is utilized completely and effectively by the body. On the other hand, the Wheat germ is considered an incomplete protein because of the lack of tryptophan (one of the nine essential amino acids), resulting in less utilization of total protein content.

Daily Protein Requirement

The Recommended Dietary Allowance (RDA) for protein is 0.8 to 1 gram per kilogram of body weight. 1 g of protein yields 4 kcal of energy which is equivalent to 1 g of carbohydrates.

Sources of Protein

The protein in animal foods like milk, egg, meat, and fish are categorized as good quality proteins because of its essential amino acid composition.

In contrast, plant proteins are of poor quality due to their non-balanced amino acid composition. This limitation can be overcome by the combination of cereals and pulses in the diet.

Protein-Rich Foods

Meat, Eggs, Fish, Poultry, Liver, Pulses, Milk, and other dairy products, Nuts, Soya bean, and soy products, and Oilseeds.

Fair Protein Foods

Cereals, Millets, Legumes, Beans, Peas.

Poor Protein Foods

Processed meat, Starch Vegetables(Potato), Green leafy vegetables.

Nuts - Vegan Protein Source

Nuts - Vegan Protein Source

Protein For Vegetarian

Vegetarians may face protein deficiency due to the consumption of incomplete protein. So vegan protein foods that withhold all the essential amino acids are recommended. Following are the protein-rich vegan food recommended for a vegetarian to meet up their daily protein requirement.

  • Soya products - It is considered as one of the rich sources of protein that provides 43g/100g approximately. Soya products include Tofu, Soy milk, Soy chunks (also called vegetarian chicken), Soy sauce, and Soy flour.
  • Cereals - Major portion of the diet includes, cereals and it places top of the food chart. Cereals include Rice, Wheat, Maize, Buck Wheat, and Oat Bran.
  • Pulses - Most of the pulses acts as the regular source of protein for vegans. It includes Bengal gram, Red gram, Amarnath, Channa Dhal, Masoor dhal, Moong dhal, etc.
  • Oil Seeds - Oilseeds are a rich source of protein as well as essential fatty acids. High protein seeds include Peanuts, Gingelly, Cashew, Almond, Sesame seeds, pumpkin seeds, and flax seeds.
  • Fruits - Fruits are rich in fiber, but there are a few exceptions with the high level of protein. It includes Avacado, Kiwi, Guava, Jack fruit, Apricot, and Blackberry.

Tip for protein intake in your meal

To improve the protein quality of your diet, the cereal and pulse portion can be in a 4:1 ratio. In addition to this, two to three servings of pulses are taken a day. It is one of the secret ingredients for a balanced diet too.

Protein in Egg

Egg contains good quality protein, and we usually include either hen or duck egg in our meal. Egg yolk is a good source of iron, vitamin A, riboflavin, folic acid, and vitamin B12.

An egg weighs between 40-50 grams and is composed of three layers including, egg white, yolk, and outer shell. The egg is a rich source of protein and is used as the standard for evaluating protein quality in other foods.

Egg - Rich Source Protein

Egg - Rich Source Protein

Nutrient composition of Egg

Protein in 1 Egg



88.0 %

48.0 %


11.0 %

17.5 %


0.2 %

22.5 %


0.8 %

2.0 %

Protein for Weight Loss

Protein not only helps to strengthen muscles but also helps in weight loss. Protein makes you feel filled and reduces the hunger hormones to encourages less intake of carbohydrates and fats.

Protein requires a similar amount of energy (4 kcal) as carbohydrates to synthesize. Thus, protein increases the metabolic rate of the body to reduces the storage of protein as fat.

Lack of protein during your workout routine will lead to muscle loss instead of fat reduction and leads to a starving state.

To attain ideal body weight, heavy workouts along with high protein food are recommended. Approximately 25% to 30% of protein is to be included in your meal per day.

Following are the protein foods included during your weight loss routine,

  1. Egg - Whole egg is composed of vitamins, minerals, fatty acids, antioxidants, and other nutrients that you need. Egg white is suggested during the weight loss routine.
  2. Meat - Boiled meat is consumed. It includes chicken, turkey, lean beef, port, etc.
  3. Fish - Steamed fish and avoid deep-fried or shallow-fried fish.
  4. Legumes - Kidney beans, chick beans, etc.
  5. Diary Product - Milk, cottage cheese, plain yogurt, buttermilk.
  6. Fruits - Avacado and guava.
  7. Whey Protein Powder - Supplements are the best suit for vegans to meet up their protein need. It is used to increase muscle strength and helps in weight loss.

Whatever the diet plan you adopt, calorie in and calorie out is a crucial part of your weight loss routine.

Man needs essential nutritious food for proper growth and development and to lead an active and healthy life.

This blog gave you a clear picture of Protein requirements and their importance in day-to-day life.

Stay fit and healthy. Stay safe :)

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2021 Myvizhi Palanisamy

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