Protein foods such a meat, poultry, fish, eggs, cheese and milk clog up the basal membranes of the blood vessels and reduce nutrient supply to cells, including those of the brain. These proteins cannot be used by the body, partially becasue they are coagualted (heated) or degenerated by enzymes within dead cells (of diseased animals). Pasteurized protein foods (dairy) are not absorbed through cell walls and also clog up membranes and lymphatic vessels. As such, they hinder the removal of metabolic waste products and turned over cells, reason enough to cause diminished brain activity and proper blood circulation.
Most amino acid/protein needs are covered by the carbon, nitrogen, ogygen and carbon molecules contained in the air your breathe. Hence, it is nearly impossible to run out of protein unless your liver and lungs are dysfunctional. Gorillas, elephants, cows, etc. make their protein in the same way. I have not been eating protein food for 17 years now and my brain works very well.
Unless you eat protein foods in raw form, you cannot derive protein from protein foods. If you cook an egg, its proteins in the egg yolk coagualte. If you cook, fry or heat meat or fish your coagulate the protein. In other words, you destroy it and make it useless for the body. What it will do for you is trigger an immune response (meat is a stimulant) that provides you with energy and makes you feel stronger. How often you can repeat this response depends on your constitution. A typical person can live with it for 40-50 years before she develops heart trouble or diabetes or lung problems as a result of depositing excessive protein in her blood vessels.
Animal protein such as meat, fish, poultry is derived from carcasses. This means that there is no more oxygen supplied to the cells of the animal. By design, enzymes present within all cells (including ours) begin to destroy the protein that makes up the cells within minutes of their death. Hence, meat that is not treated with preservatives (carcinogenic chemcicals) looks grey-greenish, not pink or reddish. This causes "degenerate protein" which the body recognizes as "damaged" and tries to eliminate as quickly as it can (immune response). Of course, most protein foods people eat are cooked and coagulated. Many lymph-related diseases result from ingesting degenerate proteins. Makes you wonder why some "uncivilized" tribes or people in different places in the world eat fish, worms, insects, etc. alive.
Our body has only about 20 Percent of the hdrochloric acid avaialable that a carnevorous animal has to to digist the same kind of meat. Our body has a 18-ft long small intestine, about 20 times longer than that of lion. Meat is not supposed to stay in the small intestine longer than 1/2 hour. In the human body, though it takes a minumum of 8-24 hours. This unavoidedly leads to putrefaction of the carcasses. Parasites thrive in such an environment. It is, therefore, natural for the body to develop a major immune response, making you feel stronger and more grounded, at least for a while.
Also, regularly being exposed to foreign DNA (from animal protein) weakens the immune system and causes disease. If you give cows animal feeds they develop brain disorders. They cannot digest animal proteins. Why would they need to? Elephants, gorillas, and the incedribly strong giraffs don't eat protein to make their strong muscles. They make it, like we do. Most of our and their protein comes from amino acids that are manufactured in the body. All amino acids are made from nitrogen, oxygem, carbon and hydrogen molecules. These, in turn, are ingested through inhaling air (air is composed of these four elements). Hence these super strong animals don't run out of protein. And hence you and I never run out of protein either unless we develop congestive lung problems and run out of the building blocks of amino acids. For the same reason, human breast milk doesn't contain protein, babies make their own from the air they breathe.