Protein: Essential Nutrient for Human Body


  • Chatrapa Hudthagosol Department of Nutrition, Faculty of Public Health, Mahidol University, Thailand
  • Maneerat Techavichian Department of Nutrition, Faculty of Public Health, Mahidol University, Thailand


Protein, Amino acid, Protein quality, Health consequences of protein deficiency, Health consequences of excessive protein


Protein is an essential nutrient for human bodily functions. Protein is presnt in both animal and plant food sources. Proteins from animal source foods provide complete protein since they are composed of all essential amino acids and in adequate quantity. On the contrary, plant proteins are incomplete protein as they contain fewer essential amino acids or in low quantity, hence these sources alone are inadequate in meeting the protein needs for human body. When human ingests dietary proteins from plant and animal foods, proteins are broken down to amino acids by gastric acid and digestive enzymes. These amino acids are used for building the body proteins for performing many functions in our body. However building proteins to meet the body needs require all 20 amino acids, therefore it is important to consume varities of protein foods from both plant and animal source foods. For vegetarians, it is recommended to consume 2-3 types of plant source foods to complement the protein quality.  Adequacy of protein intake can be determined by the knowledge on nitrogen balance which can assist health-care providers to plan proper diets for patient management. For maintaining good health, individuals should not consume too little or too much dietary proteins. The health consequences of protein deficiency and excessive protein result in dysfunctional organs that cause multiple clinical symptoms.


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How to Cite

Hudthagosol, C., & Techavichian, M. (2020). Protein: Essential Nutrient for Human Body. Journal of Nutrition Association of Thailand, 55(1), 82–94. Retrieved from



Academic article