Amino acids (essential and non-essential): understand the function

We hear a lot about proteins , which are present in the constitution of the body in large quantities.

Even though our body is composed of about 250 thousand different proteins, they are formed by different combinations of just 20 amino acids. And the organism can only produce 11 of them.

But after all, what are these amino acids? We will understand a little more below about this essential component.


What are amino acids?

According to the Institute of Medicine (IOM), amino acids are the main structural and functional component of all cells in the body.

They play a fundamental role in the formation of proteins, which are the main sources of building and maintaining body tissues.

Amino acids correspond to about 20% of the body’s weight, already in the form of protein molecules, such as keratin, collagen, blood transport molecules, etc.

In nature it is possible to find several amino acids, but only 20 of them appear in the human genetic code and they are divided into two groups: essential and non-essential amino acids.

The body needs the intake of these essential nutrients, since the body is unable to produce.

Their absence can lead to weight loss, impaired growth (especially in children) and some other clinical symptoms.


They are the amino acids that the body cannot produce alone. For that reason, we have to get them through food or dietary supplements.

There are 8 in total, including histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.

Animal foods (meat, dairy, eggs, etc.) contain all the essential amino acids. Those of plant origin, on the other hand, have a smaller variety of these nutrients.

For fans of vegetarian diets, it is necessary to balance food intake so that they do not develop a lack of amino acids. You must choose:

  • Grains and cereals (rice, wheat, oats, quinoa and chia);
  • Legumes (soybeans, beans, chickpeas and lentils);
  • Vegetables (broccoli, spinach, cabbage, lettuce and chard);
  • Fruits (açaí and banana);
  • Oilseeds (chestnuts and walnuts).


Despite the name, non-essential amino acids are essential for the proper functioning of the body. They are also known as natural amino acids.

They receive this name because they can be produced naturally by the human body and synthesized by the liver (transformed into proteins).

They represent a total of 12 amino acids, which are: alanine, arginine, asparagine, aspartate (aspartic acid), cysteine, glycine, glutamate (glutamic acid), glutamine, methionine, proline, serine and tyrosine.

But the organism is not always able to produce all of them in ideal quantities.

In such cases, it is recommended to consult a nutritionist who will indicate the use of supplementation or a diet that includes specific foods for the replacement of nutrients.

What is the role of amino acids in the human body?

The main function of amino acids is to act as part of the structuring of protein molecules, which are responsible for a large part of the human body’s processes.

In addition, they are important in the transport and storage of nutrients. Everything in our body is the result of the work of proteins and, therefore, of amino acids.

The lack of one of them is enough for thousands of proteins essential to the human body to stop being produced, which can cause health problems.

It is worth mentioning that each of the 20 amino acids performs a specific function, resulting in different actions and benefits to the organism. Check out some of them:

  • Glutamine: abundant in blood and muscle tissue, strengthens the immune system and promotes the health of the intestinal system;
  • Lysine: stimulates the development of the body, as it helps to increase the natural production of GH (known as growth hormone);
  • Tryptophan: helps in the formation of the neurotransmitter serotonin (known as the wellness hormone). Reduces anxiety, depression and stress;
  • Leucine: helps in the repair and recovery of natural fibers, accelerating the healing processes of bones, skin and tissues;
  • Valine: acts in the repair of muscle tissues and reduces appetite;
  • Isoleucine: acts as an energetic substrate that prevents muscle fatigue. Together with leucine and valine, it composes BCAA (Branched Chain Amino Acids);
  • Phenylalanine: relieves muscle pain, increases endorphin levels and decreases the desire to eat sweets;
  • Alanine: contributes to metabolism functions to obtain energy;
  • Threonine: is involved in the natural production of collagen and elastin;
  • Methionine: helps in the body’s immune response, and its lack can cause hair loss;
  • Arginine: improves memory, increases focus and concentration, helps with physical endurance and better performance in physical activities.

What are natural amino acids?

Natural amino acids are those that can be produced by the human body, the so-called non-essentials .

They are called natural because they are produced and converted into proteins naturally by the human body.

There are 12 natural amino acids in all: alanine, arginine, asparagine, aspartate (aspartic acid), cysteine, glycine, glutamate (glutamic acid), glutamine, methionine, proline, serine and tyrosine.

Where to find amino acids?

We have already seen that amino acids are fundamental for the functioning of the human body.

Some of them are produced by our body and others are not. However, they can be found in some foods and dietary supplements.

That said, it is important to look for a specialist and check the level of the substance to determine what is the best indication for replacement.

Check out some sources where we can find the amino acids:


Many amino acids play a key role in building and maintaining muscle structure.

For this reason, some of them had their formulas synthesized for the manufacture of food supplements, indicated in general for athletes and practitioners of regular physical activities.

Some examples of these synthesized amino acids are Valine, Leucine and Isoleucine, responsible for reducing the feeling of fatigue and tiredness .

Supplements based on amino acids can be found under the nomenclature BCAA , an acronym for Branched Chain Amino Acids or branched chain amino acids (leucine, valine and isoleucine).

It is important to note that the use of these substances needs to be supervised by specialists, as their formulation has a higher concentration of amino acids than that found in food.

Here are some suggestions for supplements formulated with amino acids:

  • BCAA 2400 Max Titanium;
  • Aminofor BCAA;
  • BCAA 4:1:1 Drink Max Titanium;
  • BCAA Top Integralmedica;
  • BCAA 2400 Millennium Probiotics .


Amino acids can be found in foods in the form of proteins. When consumed, during the digestion process, our organism breaks down its molecules.

In this way, proteins are synthesized and transformed into free amino acids (the final product of digestion), which enter the blood vessels and are transported to the liver.

Here are some foods rich in amino acids, and of which types:

Animal foods

Animal foods have proteins of high biological value and provide us with all the essential amino acids for the body.

Some foods such as lean meats, eggs, milk and its derivatives contain the 9 essential amino acids as well as the 11 non-essential ones that the body requires to function properly.

But that does not mean that only animal proteins should be ingested.

According to some doctors, these products, despite containing all the essential amino acids, imply the consumption of large amounts of fats, which is not the case with vegetable proteins.

Here are some foods with significant amounts of amino acids:

  • Tuna fish;
  • Cod;
  • Chicken meat;
  • Bovine meat;
  • Pig meat;
  • Rabbit meat;
  • Milk and dairy products (yogurt, cheese, etc.);
  • Eggs;
  • Peru;
  • Salmon;
  • Sardine;
  • Vieira.

Plant-based foods

Not all plant foods contain all the essential amino acids. Therefore, the ideal is to eat varied vegetables, in order to get the necessary amount of each one with this combination.

For example, brown rice contains little lysine and threonine and lentils have a limited amount of methionine.

If we make a dish that combines brown rice with lentils, we will have a complete and balanced meal.

There is no need to combine amino acids in the same meal, as the liver stores them and supplies them to the body when necessary. But it is important to consume them in a varied way.

Here are some foods that contain essential amino acids for the body:

  • Açaí;
  • Amaranth;
  • Banana;
  • Potato and sweet potato;
  • Broccoli;
  • Beans and lentils;
  • Green leaves (lettuce, chard and cabbage);
  • Chickpea;
  • Nuts;
  • Pistachio;
  • Quinoa;
  • Hemp seeds;
  • Soy;
  • Buckwheat.

It seems to be very difficult to follow a balanced diet in order to supply all the proteins that our body needs to function properly.

But it really isn’t! The important thing is to seek the accompaniment of a (a) specialist, who will help to compose a balanced menu or indicate the ideal supplementation for this function.

Did you already know the amino acids? Are you looking to follow a diet or take supplements to keep your protein levels balanced?

Tell us in the comments and keep following the Healthy Minute to learn more about food and health.