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For our body to function properly, the intervention of different amino acids is necessary, especially those that are essential. The isoleucine is one of these, further, it characterized by belonging to the branched chain amino acid . This makes its functions even more important for the body.

That is why we will talk to you in detail about this amino acid below. So that you can learn from what isoleucine is, to how it works in the body, and hat is its recommended dose, as well as some of its benefits and adverse effects.

What is isoleucine?

Isoleucine is part of the 8 main amino acids that the body needs, which is why it is considered an essential amino acid.

It should be noted that since the body cannot produce or synthesize this amino acid on its own, it must first be ingested through food sources that contain it, to later be digested by proteins.

Who discovered?

Isoleucine was discovered in 1904 by Paul Ehrlich , who was a leading German chemist. As far as its discovery is concerned, several things are said. The first is that this amino acid was discovered in molasses solubles .

While the second refers that the composition of isoleucine could be obtained through chemical processes that involved a degradation to d-isoamylamine. Producing later, its synthesis by means of d-isovaleraldehyde.

Chemical composition

The molecular formula of isoleucine is composed of Carbon, Hydrogen, Nitrogen and Oxygen. As far as its nomenclature is concerned, it is ‘lle’ or ‘l’ . However, this amino acid is also often known by the name ‘2-amino-3-methylpentanoic acid’.

Also, as mentioned above, isoleucine is part of the branched chain of amino acids. Being together with Leucine as well as Valine, which are also of vital importance for the body.

How does isoleucine work in the body?

Among the functions that this amino acid has, it is mainly that of contributing to the proper functioning of the body. Therefore, isoleucine takes care of several tasks . On the one hand, it is responsible for consists of constituting fatty acids, while on the other, it performs the same function, but with ketone bodies.

In addition, once this amino acid has been assimilated by the body, it performs two tasks mainly within it. The first is to be partially synthesized to make its constitution with proteins. While the second, what it does is contribute to the production of energy, in conjunction with vitamin B12 .

However, before all this, the amino acid is absorbed through the small intestine, to later reach the liver system through the bloodstream.

Metabolism and Catabolism

Once isoleucine is in the body, it is converted to acetyl coenzyme A (Acetyl CoA). Thus, Acetyl CoA is in charge of mediating between the different tasks that are taking place in the body.

It should be noted that the catabolism of isoleucine together with others of the branched chain of amino acids is capable of generating ATP . This is due to the fact that initially this catabolic process takes place in the muscles.

Consequences of poor catabolism

When the catabolism of isoleucine as well as of the other amino acids belonging to the branched chain is not carried out efficiently, some genetic pathologies can occur. Found mainly among some of them the following:

  • Neurological problems, including mental retardation.
  • The disease in the urine known as ‘Maple Syrup’.

One of the main conditions for poor catabolism of essential acids in the body, is the just mentioned ‘Maple Syrup’ urine disease . This one bears that name, due to the particular smell that people affected with this disorder can present.


This function carried out by isoleucine, basically what it is in charge of is synthesizing and constituting the body’s proteins. Since , without the presence of this amino acid, these processes cannot be carried out .

Therefore, it is believed that isoleucine is essential for important functions to be carried out, such as developing antibodies in the immune system, as well as other types of activities that involve some hormones.

Why is isoleucine important for the body?

As mentioned at the beginning, isoleucine is part of the 8 essential amino acids of the body, thus being of great importance for its proper functioning. In addition, it allows different processes to be carried out, such as:

  • Let hemoglobin be produced.
  • That regenerative processes are carried out in the skin.
  • It helps to level glucose levels in the blood (it can even replace it).
  • Allows nutrients to build up in cells.
  • It can contribute to the production of energy during physical training.

Remember that isoleucine is also present in our muscle tissue, as well as in part of the genetic code. This is one of the main reasons why it is so important for our body.

Isoleucine benefits

Isoleucine has a wide number of benefits for our body. However, among the main ones, those that involve both the circulatory system as well as the blood one stand out. Finding among some of them the following:

In the circulatory system

Isoleucine plays a vital role in the generation of hemoglobins in the blood. And it is well known that these hemoglobins are responsible for two fundamental tasks:

The first is to allow oxygen to travel and return efficiently , from the lung area to the entire body. While the second task is responsible for helping both to keep blood sugar levels level, as well as to give it its characteristic red color.

For all this to be possible, it is necessary for the body to synthesize isoleucine before, since otherwise, these white blood cells could not be produced. That is why this amino acid becomes an important part both for the proper functioning of the circulatory system as well as the bloodstream.

In muscle tissue

It is well known that all essential amino acids contribute greatly to the body working in optimal conditions. However, unlike others, isoleucine is able to contribute to fat loss . This is possible due to the actions that this amino acid performs on the metabolism when it is in a passive state.

In addition, like other essential amino acids belonging to the branched chain, isoleucine has the quality of avoiding as much as possible the deterioration of muscle tissue , making it preserved.

Therefore, it is also believed that this amino acid can contribute to muscle and skin regeneration processes after injury.

What foods contain isoleucine?

Diet is the only way the body can get isoleucine . That is why it is necessary to adopt a diet rich in this amino acid, through the different food sources in which it is present, such as:

Foods of animal origin

Animals contain significant amounts of isoleucine, this despite the fact that they do not produce it.However, they can be found mainly in the following:

  • Birds.
  • Chicken.
  • Fish.
  • Mutton.
  • Dairy products.
  • Eggs.

Vegetarian food

In addition to animals, there are also different foods of plant origin, as well as grains, cereals and legumes in which this amino acid can be found, such as:

  • Lentils.
  • Some cereal grains and nuts.
  • Integral rice.
  • Peanuts
  • Garbanzo beans.
  • Seaweeds .

It is important to avoid overindulging in foods that contain this amino acid, as anything in excess can be harmful . Therefore, it is recommended that you go to a nutritionist or health professional who can indicate the balanced diet to follow according to your case.

Adverse effects of isoleucine

All essential amino acids, as their name indicates, are necessary for the body. Especially isoleucine, standing out greatly over other essential amino acids for being part of the branched chain of amino acids.

Thus, in terms of the adverse effects that the excess or lack of isoleucine consumption can bring, the following can be found:

Isoleucine deficiency

As has been seen, a bad catabolism process of this amino acid in the body can lead to different genetic diseases. Likewise, among other quite common symptoms that can be produced by the deficiency of isoleucine in the body, the following can be found:

  • Tiredness.
  • Irritability.
  • Problems with the functioning of the digestive system.
  • Headache.
  • Depression.

It should be noted that people with vegetarian diets are usually more exposed to suffering from isoleucine deficiency in their bodies, since this amino acid is present in a wide variety of foods of animal origin.

That is why, to avoid said deficiency, it is important to include in the diet both vegetables, as well as cereals and legumes that contain this amino acid. Seeking thus, to replace through these the necessary amount of isoleucine that the body requires to function properly.

Isoleucine excess

Although it is not common to see conditions related to excess isoleucine, there are cases where this scenario occurs. In them, the affected people are usually those who mainly suffer from kidney problems .

This is due to the fact that, in general, the renal system is responsible for discarding the amino acid residues that are not synthesized in the body, this process occurring through the urine. Therefore, by not having the renal capacity to properly dispose of excess amino acids, a saturation produced by an oxidative process can be generated.

Recommended dose of isoleucine

As has been said, around 600 mg is the recommended daily dose of this amino acid in people who do not participate in sports or much physical activity. So, in most cases, eating a balanced diet with foods that contain this amino acid can be more than enough.

Likewise, it is believed that the amount of isoleucine to ingest daily can be calculated by multiplying each kilo of our weight by 10 mg of this amino acid. However, those who do constant sports training or activities that involve intense physical exercise, may need supplements to obtain better results in their practices.

However, before increasing or decreasing the amount of isoleucine that is ingested daily, it is advisable to go to a nutritionist or health professional. Since, it can evaluate your case specifically and indicate the recommended amount of isoleucine that you should ingest.

Are there differences between isoleucine or L-isoleucine?

It is common to find this amino acid with the letter ‘L’ before its name in some types of supplements. However, isoleucine with or without the letter ‘L’ before it, fulfills the same type of functions as such.

The only differentiation made by this letter is to indicate the state in which this amino acid is found. Well, the letter ‘L’ before the name indicates that it is found as a Levorotatory compound . This state basically allows the small intestine to carry out the metabolization process with less difficulty.

Consult your nutritionist before taking isoleucine supplements

As has been seen, isoleucine is one of the most important essential amino acids on which the body depends for its proper functioning. That is why it is important to eat a diet where foods that contain this amino acid are eaten in a balanced way.

However, in case of suffering from any type of disease, especially kidney disease , it is best to see a health professional. Since that way, you will be able to know the necessary dose of isoleucine that you should ingest daily.

Even if you are in good health, you should not implement any type of supplement that contains this amino acid without first having the respective supervision and medical prescription.

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Hello Readers, I am Nikki Bella a Psychology student. I have always been concerned about human behavior and the mental processes that lead us to act and think the way we do. My collaboration as an editor in the psychology area of ​​Well Being Pole has allowed me to investigate further and expand my knowledge in the field of mental health; I have also acquired great knowledge about physical health and well-being, two fundamental bases that are directly related and are part of all mental health.

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