Amino Acids, Essential Amino Acids and Protein Explained

Amino acids are often referred to as the building blocks of life - and that's for a good reason! They play a crucial role in many aspects of your health. From forming proteins to carrying out various essential biological functions in the human body. With 20 different types that can combine in countless ways, amino acids provide the foundation for a strong and healthy body!

Out of 20 amino acids, nine are considered "essential" – meaning your body can't produce them on its own and they must be obtained through your diet. On the other hand, the remaining 11 are "non-essential", as your adult body can synthesise them by itself when needed. But regardless of their classification, ALL amino acids contribute to your overall well-being and should be an important part of your daily nutrition!

In order to achieve this, it's first and foremost important that you consume a well-balanced diet. Many foods such as meat, dairy products and legumes are excellent sources of proteins - and with that, amino acids. Let's have a look at all their benefits and how to get the most out of them.

Protein, Amino Acids and Essential Amino Acids

Amino acids can connect to form proteins - you can think of them as the bricks that form a building. The sequence in which specific amino acids connect plays a pivotal role in the final structure and function of the protein. There are 20 distinct amino acids, each bringing its unique touch to the mix. Common amino acids you might come across include glycine, arginine, tyrosine, glutamine and threonine, just to name a few examples. Each plays a special role, much like ingredients in a complex recipe.

Chemically speaking, every amino acid (as the name indicates) possesses an amino group and a carboxylic acid group. But besides this, each of them has a unique, specific carbon structure - its "side chain". It's this side chain that gives each amino acid its unique properties and influences the shape of the final protein. 

Here's something important to note: Out of the 20 amino acids, nine are termed 'essential', meaning our body can't produce them on its own. These essential amino acids include tryptophan, lysine, histidine, methionine, leucine, phenylalanine, threonine, valine and isoleucine. They must be sourced from our diet. Then, there are nonessential amino acids, which our body can synthesize, such as serine and tyrosine. Beyond these, some amino acids - like arginine - are "conditionally essential", meaning under certain conditions or stress, the body might require an external source [1]. A well-rounded diet ensures you're supplying your body with all the vital amino acids it needs at any given time.

The Building Blocks of Life and Protein Synthesis

We already know that amino acids play a crucial role in your body as they are the building blocks of proteins. These proteins on the other hand are essential for various vital functions, such as cell growth and energy metabolism. Let's explore the importance of amino acids and their diverse functions in your body in a bit more detail:

Firstly, amino acids are required for protein biosynthesis [2]. Proteins make up a significant portion of your body's cells. These proteins are responsible for various functions, including enzymes that aid in digestion and metabolism, as well as structural components like collagen in connective tissues - and of course muscle protein. This explains why maintaining a proper balance of amino acids is essential for your body's growth and development.

Additionally, amino acids are critical in the production of neurotransmitters [3]. These chemical messengers allow your brain cells to communicate effectively, ensuring proper cognitive function. For example serotonin - a neurotransmitter derived from the amino acid tryptophan - regulates mood and sleep. Understanding the role of amino acids in neurotransmitter production can help you maintain a healthy nervous system.

Amino acids also play a role in energy metabolism by serving as fuel for your body's cells [4]. Some amino acids can be converted into energy when needed, providing an essential source of fuel during periods of increased physical activity or when other energy sources are scarce. Being aware of their role in energy production can help you maintain optimal energy levels throughout the day.

Last but not least, amino acids contribute to several other essential functions within the body. They help for example in the production of hemoglobin, the protein that transports oxygen within your blood. They are also involved in the formation of antibodies - which are crucial for a healthy immune system [5]! 

In summary it's safe to say that amino acids serve numerous vital roles in your body! From protein synthesis and neurotransmitter production to energy metabolism, immune function - and beyond. 

Amino Acids in Our Diet and Protein Recommendations

Consuming a variety of protein-rich foods is a great starting point to maintain overall health. But in addition to the quantity of protein you consume, you should also pay attention to the quality of the protein sources you're eating! Let's have a look at what that means: 

So-called "complete proteins" contain all nine essential amino acids in the right proportions. Proteins that are not considered "complete" may lack one or more. Animal proteins like meat, fish, dairy products and eggs are generally considered complete proteins. There are plant-based options as well, like quinoa, pea and soy. Combining different plant-based sources - like for example beans and rice - can also easily provide all essential amino acids your body needs!

Digestion is a key process when consuming amino acids, as it breaks down dietary proteins into individual amino acids and polypeptides. These smaller components can then be used by your body to build new proteins as needed. Some proteins (for example whey protein) are digested faster than others (for example casein). 

Though animal proteins are often considered high-quality sources of amino acids, they can also contribute to an increased saturated fat intake and they lack dietary fibre. To maintain a well-balanced diet, try incorporating many plant-based sources like soy, beans, and quinoa! They are not only rich in amino acids but also contain fibre and essential nutrients.

Supplements can be a convenient option if you struggle to get all essential amino acids through whole foods alone. With many options available, there is a protein powder for everyone. Just make sure it fits into your dietary requirements, has a balanced amino acid profile, high protein content, and tastes great!

Amino Acids - A Summary

In this quick overview of amino acids, we tried to explore their intricate role as the building blocks of proteins and their importance in numerous biological processes. Through a deeper understanding of essential, nonessential, and conditionally essential amino acids, you now have a clearer picture of their contributions to your overall health.

When thinking about the dietary significance of amino acids, it's evident that a well-balanced protein intake is important. Prioritise not only the quantity, but also the quality of the proteins you eat. Armed with this knowledge, we hope you're now better equipped to make informed choices about your diet and health! As always, don't hesitate to reach out to us if you have any questions. We're happy to help!

Sources

[1] Stechmiller JK, Childress B, Cowan L. Arginine supplementation and wound healing. Nutr Clin Pract. 2005 Feb;20(1):52-61. 

[2] Church DD, Hirsch KR, Park S, Kim IY, Gwin JA, Pasiakos SM, Wolfe RR, Ferrando AA. Essential Amino Acids and Protein Synthesis: Insights into Maximizing the Muscle and Whole-Body Response to Feeding. Nutrients. 2020 Dec 2;12(12):3717.

[3] Shah AJ, Crespi F, Heidbreder C. Amino acid neurotransmitters: separation approaches and diagnostic value. J Chromatogr B Analyt Technol Biomed Life Sci. 2002 Dec 5;781(1-2):151-63. 

[4] Kamei Y, Hatazawa Y, Uchitomi R, Yoshimura R, Miura S. Regulation of Skeletal Muscle Function by Amino Acids. Nutrients. 2020 Jan 19;12(1):261.