Protein, to power up your muscles

The term protein is originated from Greek “proteios” meaning prime. This term is very appropriate in nutrition, because protein is the most fundamental component of tissues in humans. In addition, they are used to produce hormones, enzymes and hemoglobin. They can also be used as energy; however, they are not the primary choice as an energy source.

Proteins are nitrogen-containing substances that are formed by amino acids. For proteins to be used by the body they need to be metabolized into simplest form, amino acids.

There are 20 identified amino acids which are classified into two types.

Eleven of these are called nonessential amino acids which our body can synthesize are not needed to be consumed in the diet. The remaining amino acids cannot be synthesized in the body and are described as essential meaning that they need to be consumed in our diets. The absence of any of these amino acids will compromise the ability of tissue to grow, be repaired or be maintained.

There are different food sources of protein which has varied influence on the human body. They perform essential functions throughout the systems of the human body such as

  • Growth and maintenance of tissue
  • Formation of essential body compounds
  • Catalyzing chemical reactions
  • Responding to stimuli
  • Providing structural support

Nutritional classification of protein

  1. Complete protein: These have all the ten essential amino acids in the required proportion by the human body to promote good growth, e.g., egg albumin, milk casein.
  2. Partially incomplete protein: These are partially lacking in one or more essential amino acids and hence promote moderate growth, e.g., wheat and rice proteins.
  3. Incomplete protein: These completely lack one or more amino acids. Hence do not promote growth at al e.g., gelatin.

Virtually every biochemical reaction in our body is catalyzed by a protein enzyme. All structural tissues of the body contain protein, so the importance of proteins to all aspects of life cannot be overemphasized.



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  • Healthy Eating- Important Nutrients to Know: Proteins, Carbohydrates, and Fats, NIH