One of the most important nutrients for human body is protein. It is essential for growth, repair and maintenance. Proteins are the most abundant kind of molecules in the human body along with water. Protein breaks down into amino acids. 

There are 9 essential amino acids that People must obtain from their diet in order to prevent protein-energy malnutrition (PEM) and resulting death. They are phenylalanine, valine, threonine, tryptophan, methionine, leucine, isoleucine, lysine, and hisitidine.

Protein is also needed to form blood cells.


It can be found in a wide range of food such as meat, milk products, eggs, soy, and fish.

It also can be found in whole grains and cereals however, it is limiting in the amino acid lysine or threonine, which are available in other vegetarian sources and meats.

Vegetarian sources of proteins such as legumes, seeds, fruits and nuts.

Different foods are rich in different amino acids thus a good source of protein comes from various foods.

People with healthy balanced diet rarely need protein supplements.

Different protein powders such as casein, whey, egg, rice and soy are processed and manufactured sources of protein. These type of protein powders provide and an additional source of protein for athletes and bodybuilders on the muscle’s exercise performance and recovery.


It depends on the overall energy intake. Different size of people need different amount of protein. It also depends on physical activity level and exertion as well as muscular mass increase. Protein intake is also greater during childhood for growth, during pregnancy or breast feeding and when the body needs to recover from malnutrition or after an operation.

If there is not enough Calories are taken through diet, the body will use protein from the muscle mass to match up with the energy that needed, leading to muscle loss.

You can calculate your daily MINIMUM protein intake as following…. 0.8 grams protein per kilogram of bodyweight per day according to the Recommended Dietary Allowance (RDA).

I mentioned MINIMUM as you have to take more when you do physical job or exercise regularly. Some studies say you have to take in 2-2.5 grams protein per kilograms of bodyweight to gain muscle however when you try to lose weight you still need to take in 1.4-1.5 grams protein per kilogram of bodyweight per day.

I hope it gave you a little bit more understanding about one of the most important nutrients in the human body.