Role of proteins as nutrient in the body is the most important, fundamental and indispensable. Proteins are the fundamental building blocks for all tissues, muscles, blood, enzymes, bones, cartilage, and hormones. They are absolutely indispensable, in the sense that, no other nutrient can do the functions done by proteins. It is therefore absolutely necessary for each one of us to consume adequate quantity and quality of proteins.
There is a common misconception among people that vegetarian people do not get adequate quality and quantity of proteins and hence these people need to take protein supplements. In fact, if properly and wisely mixed with each other, vegetarian diet can be a good source of quality proteins.
Plant based proteins have lower proportions of some amino acids. This deficiency is not same for all plant sources. For example Cereals have lower proportions of some amino acids while pulses and legumes have higher proportions of these ones. In short, these two groups of grains (cereals and pulses) have amino acid contents which are complimentary to each other. Therefore combination of food articles made from these two groups will result in a protein of better quality. If you happen to be a pure vegetarian, then you should note this fact and apply always in daily life.
Those proteins that can support life but can’t support growth have intermediate biological value. Examples are proteins found in pulses, legumes, cereals, lentils, nuts etc.
Proteins that can support neither life nor growth are lowest quality proteins. Gelatin is an example of this. Animals will die if they are fed gelatin as the only source of protein.
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