Dr Geoff’s next few posts answer a few questions about Protein – this first post gives a little background information to begin with:
Protein is the only major part of the diet that contains nitrogen. Proteins are large molecules composed of long chains of smaller building blocks called amino acids and around 20 different amino acids are found in protein.
Careful experiments, mostly using lab or farm animals, showed us long ago that protein is essential in the diet and that dietary proteins vary in quality depending upon the exact mix of amino acids that they contain. These basic ideas were in fact established before we actually knew what protein or amino acids were because nitrogen containing foods were shown to be essential in the early 1800s.
Meat, fish eggs, milk, nuts, soya and other dried peas and beans are generally classified as rich sources of good quality protein along with modern meat substitutes like Quorn.
Cereals foods like wheat, rice, barley and oats also have good amounts of protein although it is generally of lower quality than foods in the first list. Most fruits and vegetables contain only small amounts of protein and this also tends be of lower quality; fats and oils together with sugary foods and drinks contain little or no protein.
Check back soon for more interesting facts about Protein!