Protein can be consumed via animal sources or plant sources. Digestion of proteins begins in the stomach where proteins are broken down into amino acids. Amino acids are the smallest forms of proteins, and pepsin and hydrochloric acid help break it into these small forms so these amino acids can be digested into the system. After the stomach breaks down these proteins the pancreas sends out other chemicals (trypsin, chymotrypsin, and carboxypeptidase) to help finish the process. After the proteins are broken completely the body can absorb them and utilize their potential.
Everyone has a different amount of protein that should be consumed. This information is based on bio-individuality. People who are young differ from people who are old or sick, adolescents need a slightly higher amount of protein than adults, and children between the ages of 9 years old and 13 years old actually need even more because their bodies are still developing. Another important fact about protein is if a person is sick, injured, or experiencing an acute disease state. These types of people will also need higher amounts of protein to promote healing and repair.
What is also misleading is weight versus the amount of protein intake. It is often said the bigger you are the more protein you should be consuming. This is partly true. In fact, a person should be consuming the amount of protein of their Ideal Body Weight unless they are 30% or more overweight. Then at that point, a person should be consuming the amount of protein that is calculated to their Adjusted Body Weight.
How does a person know if they are 30% or more overweight? The BMR/RMR Calories Calculator can help you decipher that info. Nonetheless, this is the recommended daily allowance (RDA) for protein. Again, protein varies among each individual depending on age, physical activity, and disease state. Athletes, for example, can need anywhere between 1.2 g/kg of protein up to 2.0 g/kg of protein per day. They could even need to adjust daily depending on their activity days versus their non-activity days.
Knowing how to calculate protein is essential to ensure a person stays healthy. The calculator above gives a general assessment of basic protein needs. To get an in-depth assessment based on bio-individual needs and personal lifestyle, a personalized nutrition assessment would be the way to go.
Mahan, L. K. & Raymond, J. L. (2017). Krause’s food and the nutrition care process (14th Ed.). St. Louis MO: Elsevier
Ross, C. A., Caballero, B., Cousins, R. J., Tucker, K. L., & Ziegler, T. R., (2014). Modern nutrition in health and disease (11th Ed.). Philadelphia, PA: Wolters Kluwer.