What are proteins?
Proteins are chains of amino acids. Of a total 20 amino acids, 11 are manufactured naturally in the body, while the other 9 amino acids have to be obtained via diet (these are called the essential amino acids). On digesting proteins, our bodies break down the long chains of amino acids into single amino acids, which are then used to manufacture new proteins that are used for various vital body functions.
Complete vs incomplete proteins
A food is considered to be a 'complete protein', when it contains all the 9 essential amino acids. While animal food products are typically 'complete proteins', most plant based foods are 'incomplete proteins' since they may have low amounts or be missing one or more of the essential amino acids.
However, since different plant based foods have different compositions of the 9 essential amino acids, a plant based diet is proved to be a 'complete protein diet', since different food items combine to provide all the 9 essential amino acids required by our bodies.
Health issues due to too much protein
Kidney diseases: Most of us consume proteins well in excess of our Recommended Dietary Allowance (especially those who consume animal food products). An over consumption of proteins, leads to an excess build up of nitrogen that needs to be expelled through the urine. This increases the strain on our kidneys that can eventually lead to a permanent loss of kidney function.
Health issues due to the acidic structure of animal proteins
Osteoporosis: Animal proteins have a higher composition of sulphur containing amino acids, that tends to acididy the blood. Our bodies react to the blood acidity, by leeching calcium and other minerals from our bones, to form salt that can neutralise the acidity in the bloodstream and dispel it in urine.This results in a leeching of calcium from the bones, adversely impacting bone mineral density and increasing the risks of fractures, osteoporosis and other bone related problems.