Plant proteins. Why are they so important for the human body?
What are proteins? A short definition of protein - a long chain of molecules consisting of amino acids, which are connected by peptide bonds. Protein is the second most abundant...
What are proteins?
A short definition of protein - a long chain of molecules consisting of amino acids, which are connected by peptide bonds. Protein is the second most abundant substance in the body (mostly contains water - about 70%).
Proteins are present in every cell and there are many different proteins that perform different functions:
- Gives structure to nails, hair, ligaments
- Helps digest food - acts as enzymes
- Immunoglobulins (IgE, IgA, IgG) play an important role in the immune system.
- Carries oxygen - like hemoglobin
- Makes up the muscles that help the body move.
- And it even helps to see - the lens of the eye consists of the protein crystallin.
An interesting thing is that although the body is not able to directly absorb protein from food. Proteins that enter the body are broken down into amino acids with the help of enzymes, which pass through the digestive tract
tract enters the blood and is transported to the right place - cells (a large part goes to the liver, which produces a lot of different proteins). Excess protein is converted into glucose, which is not used and is converted into fat.
Until recently, it was thought that the body breaks down dietary protein into amino acids and then reassembles them back into protein. Recent studies have shown that the human body is able to absorb small peptide chains, which are made up of connected amino acids. Peptide chains have specific functions that are not yet well understood.
Amino acids
Different amino acids are needed for the body to make proteins. There are over 20 different amino acids, of which 9 are essential - the body cannot produce them and must be obtained from food.
- Phenylalanine
- Valine
- Threonine
- Tryptophan
- Isoleucine
- Methionine
- Leucine
- Lysine
- Histidine (the body can produce a small amount of histidine, but this amount is insufficient for children)
If there is a constant lack of at least one of these amino acids in food, protein production may be impaired and diseases may develop over a longer period of time, as the body uses proteins for tissue construction and cell repair, as well as for enzymes. However, not everyone agrees with this protein theory. Dr. D. Graham (representative of raw food ,who wrote the popular book '80/10/10 Diet') says that you only need 20-30g of protein per day and you can get it from fruits and vegetables.
Vegans whose main source of protein is grain products (low in lysine) may develop a deficiency of this amino acid over time. Therefore, it is recommended to eat legumes - peas, beans, which are rich in lysine and thus achieve a balance. And in order to get all the amino acids, it is recommended to eat a variety of proteins. From plant products, all the essential amino acids are contained in the cannabis sequence, the seeds of which ( Salvia Hispanica )
Here I want to emphasize that plant food has all the essential amino acids , you just need to make the right choice. Those who claim that plant proteins are inferior are very wrong and have not analyzed plant proteins and have very little information about it.
The body arranges and combines these amino acids in the appropriate order and produces the necessary proteins (the order of amino acids depends on the type of protein being produced, e.g.: muscle, enzyme, etc.). Protein molecules are large and consist of several hundred to several tens of thousands of amino acids, which are connected in branches and chains.
Protein structure
Each protein has a unique arrangement of amino acids. And this information is stored (encoded) in DNA. Proteins are made in the cytoplasm of the cell and sometimes up to 20 amino acids are joined per second. Among other things, amino acids are first combined into peptides and polypeptides, which are also called incomplete/uncompleted proteins. Peptides and polypeptides are later combined into proteins.
Many proteins have three-dimensional structures and this is the natural structure of proteins. Protein structure depends on protein function. The digestion and absorption of the protein depends on the structure of the protein. Also, the structure of the protein determines the allergenicity of the protein
How does eating protein affect health?
You will not find pure protein anywhere in nature (animals or plants). Protein is always surrounded by either carbohydrates or fat. It affects protein digestion and absorption. For example, some proteins contain substances that block the access and activity of digestive enzymes (eg: nuts, so before eating nuts it is best to soak them in water for 12-24 hours).
How are proteins digested?
Protein is digested by stomach acid and enzymes. Digestion begins in the stomach and then continues in the small intestine, where proteins are broken down into amino acids and absorbed into the bloodstream and transported to the right place.
What interferes with protein digestion?
Protein digestion is slowed down by fats and complex carbohydrates eaten together. Therefore, here you should remember the rules of combining food and eat concentrated proteins with fresh vegetables. As undigested proteins pass through the digestive tract, they ferment, release toxins and thus poison the body. Undigested proteins that enter the bloodstream through the permeable intestinal walls can cause allergic reactions.
How to improve protein digestibility and absorption?
Eating fresh vegetables improves protein digestion and absorption. Fresh vegetables contain enzymes that also help digest proteins, which are usually heat-treated and no longer contain enzymes. Good quality enzymes can be used.
It often happens that proteins are indigestible or incompletely digested due to insufficient amount of stomach acid. And this is especially true for older people. Stomach acid production is increased by eating a teaspoon of bee pollen or bread 15 minutes before a meal. Ginger, lemon, pineapple (which contains bromelain - a protein-digesting enzyme) and other natural products also stimulate the production of stomach acid. There are even stomach acid supplements.
Protein in raw food
As some followers of raw food (raw foodist) claim, proteins in raw vegetable food are in the form of amino acids and therefore the body absorbs them without spending as much energy as from cooked protein food. For this reason, the body needs less protein food. Amino acids obtained from raw food are immediately used to produce the proteins needed by the body. I can't claim that this fact is 100% true, but I think it's worth noting. Dr. G. Cousens claims that no more than 50% of protein is absorbed from heat-treated food.
How much protein do we need?
Opinions differ on how much protein a person needs per day. 0.5-1 gram of protein per kilogram of body weight is usually recommended. Athletes sometimes need more. But here the protein sources are not taken into account, because some proteins are absorbed better and others worse, and it also depends on the individual organism.
People consume too much protein
Most people (except third world countries) today consume too much animal protein. Excessive consumption of protein causes various problems: it makes the body acidic, and as a result, the body takes calcium from the bones to neutralize the resulting acid. Protein digestion puts a strain on the body and also puts a heavy load on the kidneys, as the kidneys eliminate the by-products of protein digestion, such as urea, uric acid, creatine. Unused protein is converted to fat (if those calories are unused). Also, excessive consumption of animal proteins is associated with many diseases: cancer, cardiovascular diseases (high blood pressure, atherosclerosis - narrowing and hardening of blood vessels, which is also one of the causes of high blood pressure, etc.
Animal protein causes disease?
According to T. Colin Campbell, the author of one of the largest nutritional studies - "The China Study", consumption of animal proteins causes many chronic diseases. People in rural areas of China were studied and those who ate the most animal protein were more likely to suffer from cancer, chronic diseases and other diseases common to people in western countries. What's more, T. Colin Campbell says that if more than 1.5% of calories come from animal-based foods, the risk of developing cancer is greatly increased.
Again, I'm not saying that you absolutely have to cut out animal protein, but I would definitely recommend taking it in moderation, and if you do, eat good quality plant-based protein.
The article was prepared according to:
http://www.jonbarron.com
newsletter
The book 'The China Study: The Most Comprehensive Study of Nutrition
Ever Conducted and the Startling Implications for Diet, Weight Loss
and Long-term Health (Paperback) by T. Colin Campbell
Source: http://sveikatossaltinis.blogas.lt/baltymu-svarba-27.html
