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Last Updated: May 23, 2023

Essential Amino Acids

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Dr. Parwathy MurthyPediatrician • 40 Years Exp.MBBS
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What Are Essential Amino Acids?

An essential amino acid can be best defined as an amino acid that the body cannot produce on its own, unlike nonessential amino acids. It must instead be obtained through food sources, diet, or supplementation.

Furthermore, it must be noted that out of the 20 amino acids your body needs for growth and function, as many as nine are considered essential. And as mentioned above, a human body is not capable of producing them on its own; therefore, a person must get them from the food (or supplementation) they eat.

The nine essential amino acids are:

Histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.

Despite the fact that all 20 amino acids are beneficial to your health in some way, only nine are considered essential because they are required specifically for proper bodily function.

What Role Does Each Amino Acid Play?

There are a total of nine essential amino acids, each of which has a number of important roles in your body. Here's a quick overview of what each one does:

Phenylalanine: Your body metabolizes this amino acid into the neurotransmitters tyrosine, dopamine, epinephrine, and norepinephrine. It is crucial for the structure and function of proteins and enzymes and the synthesis of other amino acids.

Valine: It is a branched-chain amino acid (BCAA) that basically helps stimulate muscle growth and regeneration. It's also involved in energy production, making it an important nutrient for athletes and bodybuilders.

Threonine: This essential amino acid is an important component of structural proteins, including collagen and elastin. These proteins play a role in the health of your connective tissues and skin. Threonine also helps with fat metabolism and immune function.

Tryptophan: This amino acid is most often associated with drowsiness and is a precursor to serotonin. It must be noted that serotonin is a neurotransmitter that helps regulate your appetite, sleep, and mood.

Methionine: This essential amino acid is known to play a pivotal role in the human body's metabolism and detoxification. Also, it is necessary for tissue growth and the absorption of zinc and selenium, minerals that are vital to your health.

Leucine: It is an essential BCAA that not only aids in protein synthesis and muscle repair, but also helps to regulate blood sugar levels, stimulate wound healing, and produce growth hormones.

Isoleucine: It is one of the three branched-chain amino acids (BCAAs), and it plays an important role in muscle metabolism. It's also heavily concentrated in muscle tissue, making it important for maintaining muscle mass. Additionally, isoleucine is essential for immune function, hemoglobin production, and energy regulation.

Lysine: This essential amino acid plays major roles in protein synthesis, calcium absorption, and the production of hormones and enzymes. It is also important for energy production, immune function, and the production of collagen and elastin.

Histidine: This is an amino acid that your body uses to produce histamine, a neurotransmitter that is vital for regulating the immune response, digestion, sexual function, and sleep-wake cycles. It's also critical for maintaining the myelin sheath, a protective barrier that surrounds your nerve cells.

What Happens If You Don't Get Enough Essential Amino Acids?

Amino acids are the building blocks of many essential processes in the human body. The nine essential amino acids play vital roles in the human body, including tissue growth, energy production, immune function, and nutrient absorption. Although they are most commonly associated with muscle development and repair, they also play a vital role in many other bodily functions.

A deficiency in any of the essential amino acids can therefore have a negative impact on multiple systems throughout the body, including the nervous, reproductive, immune, and digestive systems. Fortunately, most people are able to get all the amino acids they need from their diet or different food sources.

What Can Essential Amino Acids Help With?

Essential Amino Acids and Mood

Tryptophan is an amino acid that helps the body produce serotonin. Serotonin is a chemical that works as a neurotransmitter, and it's responsible for regulating mood, sleep, and behaviors. Furthermore, low levels of serotonin can give rise to depression.

Exercise Performance and Recovery

Valine, leucine, and isoleucine are three essential branched-chain amino acids (or BCAAs). These amino acids are taken by many people with the aim of alleviating fatigue, enhancing or boosting athletic performance, or stimulating the recovery of muscles after exercise.

Surgery and Wound Healing

If you are healing from surgery, taking amino acid supplements may help. A recent study of at least 243 people with pelvis or long bone fractures found that those who took conditionally essential amino acids for a couple of weeks after surgery had lower rates of death and medical complications than those who received standard nutrition. So, if you're looking for ways to support your healing process, amino acids may be worth considering.

How Can Your Body Get Enough Essential Amino Acids?

It's important to get essential amino acids through your diet since your body cannot produce them. There are many foods that are rich in essential amino acids, making it easy to meet your daily needs.

Foods that contain all nine essential amino acids are referred to as 'complete proteins.' Examples of complete protein sources include:

  • Meat
  • Seafood
  • Poultry
  • Eggs
  • Dairy products

Soy and pea proteins are also complete plant-based sources of protein. Other plant-based sources of protein, such as beans, nuts, and certain grains, don't contain all of the essential amino acids that our bodies need. However, you can still get all the essential amino acids from a plant-based diet by eating a variety of plant proteins every day and keeping track of them at the same time.

For instance, including beans, nuts, seeds, whole grains, and vegetables (among other sources) in your diet can help you get the essential amino acids your body needs, even if you are not eating any animal products.


Essential amino acids are the building blocks of protein, meaning they are necessary to build the proteins that make up your body’s cells. A lack of essential amino acids can lead to a variety of health issues, which is why it is so important to get enough essential amino acids. Furthermore, we hope that this article has provided you a good insight into the subject and that you've learned something new today!

In case you have a concern or query you can always consult a specialist & get answers to your questions!

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