Plant proteins. Why are they so important for the human body?
What are proteins? A brief definition of proteins - a long chain of molecules made up of amino acids, which are linked by peptide bonds. Proteins are the second most...
What are proteins?
A brief definition of proteins - a long chain of molecules made up of amino acids, which are linked by peptide bonds. Proteins are the second most abundant substance in the body (the most abundant is water - about 70%).
Proteins are present in every cell and there are many different proteins that perform various functions:
- Provides structure to nails, hair, and ligaments
- Helps digest food - works like enzymes
- Play an important role in the immune system - immunoglobulins (IgE, IgA, IgG).
- Carries oxygen - like hemoglobin
- It forms muscles that help the body to move.
- And it even helps to see - the lens of the eye is made up of the protein crystallin.
An interesting fact is that although the body cannot directly absorb proteins from food. The proteins that enter the body are broken down into amino acids with the help of enzymes, which are then absorbed through the digestive system.
The compounds enter the bloodstream and are transported to the required location - the cells (a large portion goes to the liver, which produces a lot of different proteins). The excess amount of proteins is converted into glucose, which, if unused, is turned into fat.
Until quite recently, it was believed that the body breaks down proteins obtained from food into amino acids and then reassembles them back into proteins. Recent studies have shown that the human body is capable of absorbing small peptide chains, which are made up of linked amino acids. Peptide chains perform specific functions that are not yet well understood.
Amino acids
In order for the body to produce proteins, various amino acids are needed. There are over 20 different amino acids, of which 9 are essential - the body cannot produce them and they must be obtained from food.
- Fenilalaninas
- Valinas
- Treoninas
- Triptofanas
- Izoleucinas
- Metioninas
- Leucine
- Lysinas
- Histidine (the body can produce a small amount of histidine, but this amount is insufficient for children)
If the food constantly lacks at least one of these amino acids, protein production may be disrupted, and over a longer period, diseases may develop, as the body uses proteins for tissue building and cell repair, as well as for enzymes. However, not everyone agrees with this protein theory. Dr. D.Graham (representative of raw food), the author of the popular book '80/10/10 Diet' claimsthat you only need 20-30g of protein per day and that it can be obtained from fruits and vegetables.
Vegans whose main protein source is grain products (which are low in lysine) may develop a deficiency of this amino acid over a longer period. Therefore, it is recommended to eat legumes - peas, beans, which are rich in lysine and thus achieve balance. To obtain all amino acids, it is advisable to consume a variety of proteins. Among plant products, hemp seeds and chia seeds contain all essential amino acids.Chia Seeds)
Here I want to emphasize that plant-based food contains all essential amino acids., it is just necessary to choose properly. Those who claim that plant proteins are incomplete are very mistaken and have not analyzed plant proteins, and have very little information about them.
The body organizes these amino acids and connects them in the appropriate order to produce the necessary proteins (the sequence of amino acids depends on what type of protein is 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 linked into branches and chains.
Protein structure
Each protein has its unique sequence of amino acids. This information is stored (encoded) in DNA. Proteins are produced in the cell's cytoplasm and can sometimes link up to 20 amino acids per second. By the way, amino acids are first linked into peptides and polypeptides, which are also referred to as incomplete/unfinished proteins. Peptides and polypeptides are later combined into proteins.
Many proteins have a three-dimensional structure, which is the natural structure of proteins. The structure of a protein depends on its function. The digestion and absorption of a protein are also determined by its structure. Additionally, the structure of the protein determines the protein's allergenicity
How dietary proteins affect health?
In nature (in animals or plants), you will not find pure protein anywhere. Protein is always surrounded by either carbohydrates or fats. This affects the digestion and absorption of proteins. For example, some proteins contain substances that block the access and activity of digestive enzymes (e.g.: nuts, so it is best to soak nuts in water for 12-24 hours before eating).
How are proteins digested?
Proteins are 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, which are absorbed into the bloodstream and transported to the necessary locations.
What disrupts protein digestion?
The digestion of proteins is slowed down by fats and complex carbohydrates consumed together. Therefore, it is important to remember the food combining rules and to eat concentrated proteins with fresh vegetables. Undigested proteins, while traveling through the digestive tract, become acidic, release toxins, and thus poison the body. Undigested proteins that enter the bloodstream through permeable intestinal walls can cause allergic reactions.
How to improve protein digestion and absorption?
Eating fresh vegetables improves protein digestion and absorption. Fresh vegetables contain enzymes, which also help digest proteins that are often heat-treated and no longer contain enzymes. It is possible to use high-quality enzymes.
It often happens that proteins are indigestible or incompletely digested due to insufficient stomach acid levels. This is especially common in older adults. The production of stomach acid is increased by consuming a teaspoon of bee pollen or bread crumbs 15 minutes before a meal. Additionally, the production of stomach acid is stimulated by ginger, lemon, pineapple (which contains bromelain - a protein-digesting enzyme), and other natural products. There are even stomach acid supplements available.
Proteins in green food
According to some raw food enthusiasts, raw plant-based food contains proteins in the form of amino acids, and therefore the body absorbs them without expending as much energy as it does with cooked protein foods. For this reason, the body requires less protein food. The amino acids obtained from raw food are immediately used to produce the proteins needed by the body. I cannot claim that this fact is 100% true, but I believe it is worth considering. Dr. G. Cousens states that no more than 50% of proteins are absorbed from thermally processed food.
How much protein do we need?
The amount of protein a person needs per day varies in opinion. It is usually recommended to consume 0.5 - 1 gram of protein per kilogram of body weight. Those who exercise may sometimes need more. However, this does not take into account the sources of protein, as some proteins are absorbed better than others, and it also depends on the individual's body.
People consume too much protein
Most people (except for third world countries) today consume too much animal protein. Excessive protein intake causes various problems: it acidifies the body, and as a result, the body starts to extract calcium from the bones to neutralize the acid formed. Protein digestion burdens the body, and the kidneys also bear a significant load, as they remove the metabolic byproducts of protein digestion, such as urea, uric acid, and creatinine. Unused proteins are converted into fats (if those calories are not expended). Additionally, excessive consumption of animal protein 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 increased blood pressure, etc.).
Do animal-derived proteins cause diseases?
According to T. Colin Campbell, the author of one of the largest nutrition studies - "The China Study", the consumption of animal-based proteins causes many chronic diseases. The residents of rural areas in China were studied, and those who consumed the most animal proteins were often afflicted with cancer, chronic diseases, and other illnesses typical of people in Western countries. Furthermore, T. Colin Campbell states that if more than 1.5% of calories come from animal-based food, the risk of developing cancer significantly increases.
I'm not saying that you must completely give up animal-based proteins, but I would definitely advise you to consume them in moderation and, if you do, to eat high-quality plant-based proteins.
Article 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
ir ilgalaikė sveikata (popierinis) autorius T. Colin Campbell
Source http://sveikatossaltinis.blogas.lt/baltymu-svarba-27.html
