How much protein a person needs. Daily protein intake in grams
In this article, we will talk about different daily protein intake for men and women, as well as for athletes. Where did these norms come from, and what are they now in connection with recent research. After, for example, consider how much the body actually needs per day to maintain only our muscles. I also advise you to read the article: “Nitrogen balance. How to calculate the daily rate of protein intake “ , in which you will learn how the method of nitrogen balance to calculate their individual protein norm is for your body, surrendering just one analysis, as well as an article about protein , in general. Let’s get started.
To begin with, let’s figure out who was the person who first started talking about protein norms . This man’s name was Max Rubner, he formulated the concept of anabolism and catabolism for human tissues and found out the wear coefficient, that is, how much tissue is losing protein per day. In his research, he found that a person needs only 0.3 grams of protein per 1 kilogram of body weight to avoid catabolism. According to his data and, incidentally, they are, oddly enough, often published in dietary guides, for a 70-kilogram person only 23grams of protein per day. In fact, this is a little less than a liter of milk. It is clear that if we lack protein, then our tissues will wear out faster than we recover. This will lead to a deterioration in health, tissues, etc. Many people face this: brittle hair, poor skin, poor health, etc. Read an article on protein and you will understand how serious this is.
I would like to draw attention to the fact that all this happened about 100 years ago. It was 100 years ago that he investigated and derived the wear coefficient. You understand what there were errors in the study, errors in the analysis, etc. In general and in general, this amount of protein is very small. The truth is that this coefficient was calculated for a person at rest, i.e. just lying in bed without moving. And still, this is the minimum, and it does not suit us.
In the United States, there is a standard that speaks about the protein norm ( RDA, RDI, GDA ). In general, these standards say that the average person, with an average load, with an average daily regimen, in general, an average person should take from 0.66 grams. up to 0.84g. protein per 1 kg of weight.
|7 to 12 months
|From 1 to 3 years
|4 to 8 years old
|9 through 13 years
|From 14 to 18 years old
|From 19 to 30 years
|From 31 to 50 years old
|51 in 70 years
|> 70 years old
|Protein requirements increase in the second half of pregnancy
Recommended Dietary Allowance (RDA) is the level of intake needed to meet nutrient requirements. These data are intended for healthy people at a specific life stage. You can see the table of protein norms for people suffering from various diseases (including those with kidneys) here . Although this data is also outdated, therefore, it is slightly underestimated.
These are norms accepted worldwide. But still there are nuances. The fact is that these standards imply:
- That a person will consume only high-quality protein, with a complete amino acid composition.
- In addition to consuming protein, you also need to fully provide yourself with carbohydrates and fats, and many do not.
- Data on the required amount of protein is updated every 10 years. That is, every 10 years there are studies that confirm or refute the old data. And the data presented above is already quite old.
All old data is based on the principle of nitrogen balance . It is very simple and affordable, but it has inaccuracies and inaccuracies. There are recent data that speak of a real protein norm, i.e. about how much protein actually needs to be consumed by an average person. And oddly enough, the protein norm is quite high . This study uses a new method that tracks the oxidation of amino acids in the human body. And here there are few errors, when compared with the nitrogen balance method, it is very accurate and efficient. Here is a link to the study: http://www.ncbi.nlm.nih.gov/pubmed/19841581.
As a result, it was found that the real human need for protein exceeds state indicators by 40% . That is, people do not eat up if they follow the standards established by the Ministry of Health. In these studies, it was found that in order to fully cover their need for protein, the average person should consume from 1 to 1.2 grams. protein per 1 kg of body weight . And I’m closer to the figure of exactly 1.2 grams.
Surely for athletes and for those who are already interested in these issues, the norm does not seem to be significant, or maybe even small. Athletes and bodybuilders eat a lot more protein, but for an ordinary person, these are very large numbers. Statistics say that the average person does not consume as much protein, namely 80% of the world’s population. And it is very important that we are talking about proteins that are full in amino acid composition , and in general we can say that we are talking about animal proteins . Naturally, if you use vegetable proteins correctly (the most valuable are soy protein), it is possible to cover the shortage of amino acids by combining various proteins of plant origin with animal protein. However, it is important to be able to combine all kinds of proteins in order to get your norm .
So, in the end, we have modern recommendations for the daily protein intake for average people who do not play sports and want to be healthy:
DAILY NORM OF PROTEIN = 1 – 1.2 grams * 1 kg of weight
For example, for a man in 80 kg , the norm is 80 * 1.2 = 96 g of protein per day.
Now let’s determine the daily protein intake for athletes . Everything is ambiguous here, as all people are individual: different sports, different sex, etc. However, the same studies showed that there are approximate figures for athletes.
For male athletes:
DAILY NORM OF PROTEIN = 1.5 – 2 grams * 1 kg of weight.
An exception may be bodybuilders, who may need a little more than 2 grams per 1 kg of weight . But not at all 3-5 grams , as some sports magazines tell us.
For women athletes:
DAILY NORM OF PROTEIN = 1.5 grams * 1 kg of weight.
An exception may also be women who are seriously engaged in bodybuilding, for whom the norm can increase to 2 grams per 1 kg of weight .
How much muscle “eat” protein? Hunger and catabolism
Everyone knows and understands that the human body is constantly updated and capable of recovery. The body, like a machine , is constantly exposed to various influences, it works and wears out. And, like any car, the body needs to be repaired. It’s only good that he repairs himself, is renewed and restored. All that we need is to simply throw in the necessary nutrients.
The human body consists of 220 billion cells and gradually each of these cells is updated, not all of course, but some of them are accurate. There are cells that live throughout a person’s life and, in general, are not updated, they mainly include nerve cells . For example, the intestinal epithelium is constantly updated, and this is understandable, because large amounts of food constantly pass through it. Only 3-4-5 days and the intestine is completely renewed, i.e. 4 days have passed and we have a new intestine.
The question immediately arises: “And what is needed so that the cells are constantly updated, and there are no interruptions in work”? Of course, protein ! After all, it is the main building element of any cell, however, carbohydrates and fats are also involved in the construction. Malnutrition is the scourge of modern humanity, a lot of things are said about norms. Therefore, ordinary people, and especially people involved in sports, have legitimate questions: “How many muscles and how much tissue will I lose if I don’t eat up protein?”
The rate of decay and the rate of renewal of proteins in our tissues and organs are different . Proteins of muscles or muscles, in general, are updated in 180 days , i.e. For half a year. This means that after six months we have completely updated muscle tissue. Muscle mass in a man is about 40% of the total body weight, but in women, of course, less – about 30% of the body weight. But these are people who do not exercise. For athletes, this figure reaches 50% , and for bodybuilders it reaches 70% or more.
At the moment, there are many methods that allow you to determine the percentage of muscle tissue in your body, the analyzers just got on the scales and found out how many muscles, fat, bones, etc. There is a method of gyroscopic weighing, there are scales that pass an electrical impulse through tissues and measure the density of the tissue, which determines the weight of each individual tissue, etc. You can find out more about this in the article: “Analysis of body composition . ”
Skeletal muscles consist on average of 20% of protein and the remaining 80% of water. This means that in just 100 grams of muscle tissue (human) there will be 20 grams of protein, and that’s pretty much almost like beef. Imagine that you are a training person, that you have good strength indicators, volumetric muscles, an impressive appearance. This means that approximately 50% of your body is skeletal muscle.
Suppose your weight is 1 00 kg and average height to match your weight. It turns out that your muscles will weigh 50 kg (50% of 100 kg), and everything else – also 50 kg. But if the muscles are updated every 180 days, then you will have completely new muscles after six months. In our case (with muscles of 50 kg), to find out how many muscles are renewed per day, you need to divide 50 kg into 180 days. It turns out, 270 grams of muscle is updated per day . But, as we recall, the protein structure is only 20% of muscle tissue. Therefore, 20% of 270 grams of muscle will be 54 grams of protein per day.
This is the amount of protein that is needed to maintain the normal functioning of the muscles of a person who weighs 100 kg, and in which 50% of the total weight is muscle. You should understand that 54 grams of protein is needed only to maintain muscles in a normal state, i.e. this is not growth, and this is not restoration and building up, namely, maintaining tissues at a level under normal conditions: when we do not train, when there is no load, when we just move, sit and do not exercise. And these are just skeletal muscles, everything else also needs protein , and everything else is 50% in our example.
For people who do not train, for example, for a man who has 35-40 % of skeletal muscle tissue of the entire body weight (with the protein norm described above of 1.2 grams per 1 kg of body weight), it is spent in a normal state to maintain everything the rest (organs, tissues, etc.) 0.8 grams of protein per 1 kg of body weight .
This means that in an ordinary 100 kg a man spends 0.8 * 100 kg = 80 grams of protein per day on maintaining the rest . Now let’s move on to our trained man, who also has great muscle mass.
This means that for our 100 kilogram person we get the following figures: 80 grams of protein is needed to support everything else except muscles, plus 54 grams of protein to maintain muscles. The result is 80 + 54 = 134 grams of protein per day for support only . If this person is still actively involved in sports, then he certainly needs to eat more protein per day. If we translate this figure into a norm per 1 kg of weight, we get that for 100 kg of an athlete, 1.34 g of protein per 1 kg of weight is needed to maintain his body without sports . Which roughly corresponds to the standards described above.
By the way, many may ask: “How much muscle will I lose if I don’t eat protein or starve?” In principle, for 1-2 days without food, the average person can calmly endure and not lose anything, because there is a certain supply that supports the person in good condition. Then comes the burning of fat, glycogen and protein. However, often in a person, first of all, during fasting, muscles will be wasted , especially in a trained person, because this is an excess ballast of the body. Protein from the muscles will migrate to where it is needed. In general, a trained person, in fact, turns out to be thrifty .
So it turns out that the daily loss of protein during fasting will correspond to the need for your muscles in protein, and even more, because all other tissues also need protein. We are talking specifically about muscles, and how much they will lose. It turns out that a 100 kilogram person with 50% of the muscles of the total tissue mass will lose at least 270 grams of muscle . Here we are talking about a person who goes in for sports. For an ordinary person (who has 35-40% of muscle mass), the loss will be less . But still, these calculations are approximate, because each person is individual, each has its own metabolism (who has faster who has slower), etc.