What Are Amino Acids? Top 8 Benefits And Food Sources

Medically reviewed by Ariana Fiorita, RDN Ariana Fiorita Ariana FioritaRDN linkedin_iconinsta_icon
Written by , BSc, Professional Certificate in Food, Nutrition and Health Ravi Teja Tadimalla BSc, Professional Certificate in Food, Nutrition and Health Experience: 8 years
Last Updated on

If protein is the building block of the human body, amino acids are the building blocks of protein. You may not be an athlete training for the upcoming Olympics. Neither could acing your national bodybuilding contest be amongst your priorities. But you still need amino acids. They improve your mood, concentration, physical health, sleep, and several other physiological phenomena. Which is what we will discuss in this post. Keep reading.

Table Of Contents

What Are Amino Acids? What Do They Do?

Simply stated, these are organic compounds that combine to form proteins. When the protein you take is broken down by the body, amino acids are left behind. The body then uses these amino acids to make proteins and help the body repair tissues, grow, and perform various other bodily functions. Your body also uses the amino acids to produce energy.

There are various amino acids, classified into different groups. Knowing them will help you better understand their benefits.

Back To TOC

What Are The Different Amino Acids?

Amino acids can be categorized into three groups:

1. Essential Amino Acids

These cannot be synthesized by the body and must come from food. They have a longer half-life than the non-essential ones. Even the absence of one essential amino acid (or a non-essential amino acid) can hinder the functioning of the rest.

  • Histidine
  • Isoleucine
  • Leucine
  • Lysine
  • Methionine
  • Phenylalanine
  • Threonine
  • Tryptophan
  • Valine

2. Nonessential Amino Acids

These can be synthesized by the body, and we don’t need them through food.

  • Alanine
  • Asparagine
  • Aspartic Acid
  • Glutamic Acid

3. Conditional Amino Acids

These are not essential, except during illness and extreme stress.

  • Arginine
  • Cysteine
  • Glutamine
  • Tyrosine
  • Glycine
  • Ornithine
  • Proline
  • Serine

There are various food sources that offer amino acids. But we will get to that later. First, let’s take a look at the benefits amino acids have to offer.

Back To TOC

What Are The Benefits Of Amino Acids?

1. Amino Acids Fight Inflammation

Studies have shown that orally administered amino acids display anti-inflammatory activity (1). And there is another study that talks about how branched-chain amino acids (BCAA), which include valine, leucine, and isoleucine, can help fight inflammation as well (2).

2. Boost Muscle Growth

Arginine is one amino acid, which, as per studies, has been found to boost lean body mass and strength (3).

BCAAs are the primary building blocks of muscles – they help in the growth and repair of muscle tissue. Arginine improves blood flow to the muscles. Glutamine increases water retention in the muscles and signals cell growth.

3. Reduce Fatigue

One Swedish study shows that ingestion of BCAAs can reduce exercise exertion and mental fatigue and even improve cognitive performance post-exercise (4).

Amino acids also aid better sleep, and this can help reduce fatigue the following morning.

Another study shows how the amino acid tryptophan can help relieve fatigue caused by different levels of stress.

So, if you want to reduce fatigue and improve your endurance levels, amino acids can be a safe bet.

4. Promote Weight Loss

Research shows that amino acids might boost fat loss. They can improve muscle synthesis and lead to healthy fat loss as a consequence (5).

BCAAs have also shown to suppress appetite, and this can contribute to weight loss as well (6). This can also mean a reduced risk of obesity.

5. Boost Immunity Levels

Dietary supplementation of amino acids has shown to enhance immunity status and prevent infectious diseases (7).

Among these amino acids, glutamine seems to have the upper hand. It is recognized as a potent immuno-nutrient as it can enhance immune function to a great extent. There are several studies that support the importance of this amino acid in clinical nutrition.

According to another report by the Cambridge University press, metabolism of amino acids holds great promise in boosting immune function. More importantly, these amino acids can also elevate your energy levels and accelerate wound healing.

6. Amino Acids Improve Cognitive Health

6. Amino Acids Improve Cognitive Health
Image: Shutterstock

The amino acid tyrosine was found to have beneficial effects on cognitive performance – more so during exposure to high levels of stress. And tryptophan was found to improve brain function (8).

Research also tells us that supplements containing amino acids can reduce symptoms of depression and anxiety as they are converted to neurotransmitters that boost mood (9).

7. Can Delay Aging

Amino acid supplementation can play a role in the prevention (and treatment) of sarcopenia, which is the loss of muscle tissue due to aging (10).

Arginine and carnitine help repair damaged DNA and promote skin firmness.

8. Promote Hair Growth

Your hair is made of amino acids, which is why it makes sense to believe that amino acids can promote hair growth. Though they are not a miracle potion, they sure do encourage stronger and thicker hair growth.

The amino acids particularly beneficial for hair growth include arginine, lysine, cysteine, and methionine. These amino acids work by producing keratin, the most important protein for hair. They also create red blood cells, which deliver more oxygen to the hair follicles and promote hair growth.

These are the various ways amino acids can keep you healthier. How do you make sure you get enough of them?

Back To TOC

What Are The Food Sources Of Amino Acids?

Following are the major food groups that contain the most amino acids:

  • Animal Proteins

These are also called the complete proteins. They include beef, pork, chicken, turkey, and eggs. Even dairy products like milk, cheese, and yogurt contain amino acids. Ensure your animal protein is coming from grass-fed, organic, and free-range animals.

  • Seafood

These include fish like salmon, halibut, and tuna. They also contain omega-3 fatty acids that have great benefits.

  • Nuts, Legumes, And Seeds

These are incomplete proteins as not one specific food contains all the essential amino acids (unlike animal proteins). But consuming a combination of nuts, legumes, and seeds can help. Some of these foods include soybeans, lentils, chickpeas, pinto beans, black beans, almonds, and walnuts.

  • Whole Grains

Quinoa is one food in this group that contains all the essential amino acids and is hence a complete protein. Other foods include whole wheat bread, whole grain pasta, and long grain rice.

Include a variety of foods into your diet each day, and you are good to go. You can also include high quality protein powders (in case you do physical exercise) after consulting your doctor, nutritionist or trainer. High-quality protein powders include whey protein, bone broth proteins, or even plant-based protein powders such as that of hemp, pea, or rice.

Back To TOC

What Are The Side Effects Of Amino Acids?

Excess intake of amino acids (both BCAAs and otherwise) can lead to certain side effects like:

  • Issues During Pregnancy And Breastfeeding

There is not enough information on this. So, stay safe and avoid overuse..

  • Lung Failure

Use of BCAAs in patients with ALS (amyotrophic lateral sclerosis) has been linked to lung failure. Keep patients away from them.

  • Liver Damage In Chronic Alcoholics

Use of BCAAs in alcoholics can lead to liver disease and subsequent brain damage.

  • Abdominal Issues

Certain people experience bloating, diarrhea, and even abdominal pain with arginine supplements. Arginine also lowers blood pressure, and this can be a problem if you are already on blood pressure medication – your blood pressure might be lowered way too much.

  • Impaired Blood Sugar Control (During Surgery)

Amino acids (including BCAAs) can interfere with blood sugar levels. This might interfere with blood sugar control during and after surgery. Stop taking amino acids at least two weeks before a scheduled surgery.


Amino acids constitute our body, which is why they must be an integral part of our diet. Start taking them today, and see your health changing for the better.

Tell us how this post has helped you. Just leave a comment in the box below.

Back To TOC

Expert’s Answers for Readers Questions

When to take amino acids?

If you workout, the best time to take a supplement is pre and post your session. If you don’t (but we recommend you do), you can spread it across the day in the form of the food sources of amino acids. This way, you don’t have to rely on supplements.

What are the top amino acid supplement brands?

Some of the top brands include Optimum Nutrition, Havasu Nutrition, and MuscleTech.


  1. Anti-inflammatory and analgesic properties…”. US National Library of Medicine.
  2. Branched-chain amino acids influence…”. ScienceDirect.
  3. Effect of amino acid supplementation on…”. US National Library of Medicine.
  4. Amino acids and central fatigue”. US National Library of Medicine.
  5. Whey protein, amino acid might boost...”. WebMD.
  6. Branched-chain amino acid levels are…”. US National Library of Medicine.
  7. Amino acids and immune function”. US National Library of Medicine.
  8. Amino acid and protein requirements…”. US National Library of Medicine.
  9. Understanding nutrition, depression...”. US National Library of Medicine.
  10. Amino acids and muscle loss with aging”. US National Library of Medicine.

Recommended Articles:

Was this article helpful?
Ariana is a Registered Dietitian with 17 years of experience, specializing in functional medicine and sports nutrition in the Cleveland, Ohio area. She holds a bachelor’s degree in food and nutrition sciences from Ohio University and went on to complete her dietetic internship at The Cleveland Clinic.

Read full bio of Ariana Fiorita
Ravi Teja Tadimalla
Ravi Teja TadimallaSenior Editor
Ravi Teja Tadimalla is a senior editor and a published author. He has been in the digital media field for over eight years. He graduated from SRM University, Chennai, and has a Professional Certificate in Food, Nutrition & Research from Wageningen University.

Read full bio of Ravi Teja Tadimalla
Latest Articles