The building blocks of proteins are often called amino acids. They play a variety of critical roles in your body.
They are vital for essential processes like building proteins, hormones and neurotransmitters.
Protein-rich foods like meat, fish, and soya are rich in amino acids.
As a natural way of improving mood or athletic performance, some people take amino acids as supplements.
They can be classified as essential, conditionally important, or not necessary depending on several factors.
This article will cover essential amino acid functions, food sources high in them, and the benefits of supplementation.
Amino acid are organic compounds that are primarily composed of nitrogen, carbon and hydrogen.
To grow and function properly, your body requires 20 amino acids. All 20 amino acids are vital for your health. However, only 9 are essential.
These include histidine, isoleucine and leucine as well as phenylalanine and threonine.
Your body cannot make all essential amino acids. However, you can get the essential amino acids from your diet.
Animal proteins like meat, eggs and poultry are the best sources for essential amino acids. Some plant foods, like the tofu and edamame, contain all nine essential amino acid. They are therefore “complete” sources (2, 3).
Your body uses amino acids to break down protein and use them in various processes such as building muscle or regulating immunity function (1).
Amino acids that are conditionally essential
Conditionally essential amino acids include several nonessential ones.
These are only necessary in certain circumstances like pregnancy, infancy or trauma.
For instance, while arginine may not be considered essential, your body cannot make enough when you are recovering from serious injuries or fighting cancer.
In certain circumstances, people might need to take arginine supplements in order to meet their body’s needs.
Certain amino acids such as glycine or arginine are conditionally essential in pregnancy. This is because pregnant women need more of these amino acid to support their health and that of their fetus (6, 7).
> SummaryThe body cannot produce the essential amino acids so it must get them from food. Nonessential amino acids can become essential under certain circumstances like pregnancy or illness.
There are nine essential amino acid, which each perform a variety of important functions in your body.
1. Phenylalanine. This amino acid is converted by the body into the neurotransmitters norepinephrine and dopamine. It is an essential component of the structure and function proteins and enzymes, as well as the production of other amino acid (7).
2. Valine. This is one of the three branched chain amino acids (BCAAs). It has a molecular structure that branches off one side. Valine is an ingredient in energy production and muscle regeneration.
3. Threonine. It is an important part of structural proteins such as collagen, elastin and other connective tissues. It is also involved in fat metabolism and immune function (9).
4. Tryptophan. Tryptophan, which is often associated with drowsiness and serotonin, is a precursor neurotransmitter that regulates appetite, sleep, mood, and behavior (10).
5. Methionine. This amino acid is important for metabolism and detoxification. It is also essential for tissue growth and absorption of zinc, which are important minerals for your health (11).
6. Leucine. Leucine, like valine is a BCAA which is crucial for protein synthesis as well as muscle repair. It regulates blood sugar, stimulates wound healing and produces growth hormones (12).
7. Isoleucine. Isoleucine, the last of the three BCAAs is involved in muscle metabolism. It is highly concentrated in muscle tissue. It is also essential for energy regulation, immune function, and hemoglobin production (13).
8. Lysine. Lysine is important in protein synthesis, calcium absorption and the production hormones and enzymes. It is also essential for energy production, immune function and the production collagen and elastin (14).
9. Histidine. Histamine is an amino acid that your body uses to make it. This neurotransmitter is essential for immune response, digestion and sexual function. It is essential for maintaining your myelin sheath (15), which protects nerve cells.
You can see that essential amino acids are the heart of many vital processes.
Amino acids are best known for their role as muscle repair and development, but your body also depends on them.
This is why essential amino acids deficiencies can have a negative impact on your whole body, including your nervous and reproductive systems, immune systems, digestive system, and digestive system.
However, most people can get all the amino acid they need from their diet.
> SummaryThe nine essential amino acids play important roles in the body. They are involved in many processes including tissue growth, immune function and nutrient absorption.
Although essential amino acids are found in many foods, they have been shown to be beneficial in supplement form.
May improve mood
Tryptophan is required for the production and use of serotonin. This chemical acts as a neurotransmitter within your body.
The essential regulator of mood, sleep, behavior, and serotonin are all Serotonin.
Low levels of serotonin have been associated with depression and sleep disturbances. However, there have been several studies that show that tryptophan supplements can help to reduce symptoms of depression (16, 17, 18, 19, 20).
An 11-part review of high-quality studies concluded that 0.14-3g of tryptophan daily could reduce anxiety and improve positive mood in healthy individuals (18).
This may improve your exercise performance and recovery
People take valine and leucine as well as isoleucine to relieve fatigue and increase athletic performance. They also help stimulate muscle recovery after exercising.
A 2017 small study found that resistance-trained athletes consumed BCAAs at a dosage of 0.039g per pound (0.087g per kilogram) with a 2:1 ratio of leucine and isolecine.
The BCAAs were more effective in enhancing performance, muscle recovery, and decreasing muscle soreness than those who took a placebo (20).
Eight studies were reviewed and found that BCAAs are superior to taking rest for muscle recovery and soreness relief after intense exercise (21).
A review of nine studies also found that BCAAs reduced muscle soreness and damage after resistance training in active men (22).
BCAAs have also been shown to lower the perceived exertion rating (how intense a person feels while exercising) in high-intensity exercisers (23).
This may be useful for wound healing and surgical procedures
For people recovering from surgery, taking amino acid supplements might be beneficial (24, 25, 26).
Study of 243 patients with long bone fractures and pelvis showed that conditionally essential amino acid supplementation for 2 weeks was more effective than standard nutrition (25).
Review of 20 studies on the effects of BCAAs on patients with cancer who had undergone surgery revealed that there were fewer complications post-surgery due to fluid accumulation and infections.
A study has shown that essential amino acid supplements can help to reduce muscle loss in elderly patients who have had knee replacement surgery (27).
> Summary Taking essential amino acids in supplement form can improve mood, exercise performance, recovery, and health after surgery.
Essential amino acids cannot be produced by the body so it is important to consume them through your diet.
Essential amino acids are found in many foods, so it is easy to meet your daily requirements (28).
The World Health Organization has provided the following information about the daily recommended intakes of essential amino acids. These figures are for adults and correspond to 2.2 pounds (1 kilogram) of bodyweight (29)
* Histidine: 10 mg
* Isoleucine: 20 mg
* Leucine: 39 mg
* Lysine 30 mg
* Methionine: 10.4 mg
* Phenylalanine and the non-essential amino acid tyrosine: 25mg
* Threonine 15 mg
* Tryptophan 4 mg
* Valine 26 mg
You can multiply the above numbers by your body weight in kilograms to find how much you should eat each day. A person weighing 60 kg (132 lbs) should consume 1,200mg (1.2 grams) daily of isoleucine.
These requirements can be met with almost any diet, so it’s not necessary to keep track of your individual intakes.
One 174g piece of braised chicken breast contains 55.9 grams of total protein. This is easily comparable to or greater than the 30 recommended needs.
Food sources
Complete proteins are foods that contain all nine essential amino acid compounds.
These foods are full-protein sources of protein:
* Meat
* Seafood
* poultry
* eggs
* Dairy products
Plant-based complete proteins are pea protein and soy protein (2, 3, 31, 32).
Because they lack some or all of the essential amino acid, other plant-based protein sources, like beans, nuts and certain grains are considered incomplete proteins.
If you eat a plant-based diet, however, you can still get all nine essential amino acid by eating a variety plant proteins every day.
You can meet your essential amino acids by choosing from a variety plant-based protein sources, including beans, nuts, seeds and whole grains. This is even if you do not eat animal products.
> SummaryMany animal- and plant foods such as meat, eggs and quinoa contain all nine essential amino acid and are considered complete protein.
Many people consume enough essential amino acid through their diet.
There are many benefits to essential amino acid supplementation. They are often used by athletes to improve their exercise performance and recovery.
A review of 10 high-quality studies that looked at the effects of BCAAs on delayed onset muscle soreness after exercise (322) found that BCAAs as high as 115.6 mg per pound (255mg per kg) could be effective in reducing it.
People may also choose to take individual amino acid supplements, instead of blending them, to support specific aspects of their health such as mood.
One review of 11 high-quality studies concluded that 0.14-3 grams daily of tryptophan could improve mood (18).
As you can see dosing is dependent on what type of amino acids you are taking and your goals.
Most people are safe to take amino acid supplements. They are usually not required if you have enough protein in your diet.
However, certain groups may find specific benefits from amino acid supplements.
Talk to a healthcare professional if you are interested in essential amino acid supplementation, such as your doctor, registered dietitian, or pharmacist.
You can get advice from them about the best dosing for you and how to use your supplement to meet your specific health goals. They can also help you select a supplement brand that is trusted and has products that have been tested by third-party organisations.
> SummaryThe reason you are using an amino acid supplement and the amino acid itself will determine how to use it. If you’re interested in taking essential amino acid supplements, consult a qualified healthcare professional.
You must consume nine essential amino acids: histidine (isoleucine), leucine and leucine; lysine (methionine), phenylalanine threonine and tryptophan.
They are vital for many functions in your body, such as protein synthesis and tissue repair.
They may also prevent muscle loss and support recovery from surgery.
These essential compounds can be found in many plant- and animal-based foods. This means that most people can eat a healthy and balanced diet. If you are in need of essential amino acids supplements, you can take them.
Only one thing
Consider this: Increase your intake of protein if you are concerned about your intake of essential amino acid.
You can meet your amino acids by adding protein sources like eggs, fish, and Greek Yogurt to your meals and snacks.
This article provides more information about plant-based protein sources.
