Amino acids: the building blocks of protein
- Reading time: 9 min.
Protein is important for various physiological processes in our body. Especially for strength athletes and bodybuilders, it is important to get enough protein. This is because they help recover after a hard workout and stimulate the building of muscle mass. But how are proteins actually constructed? Proteins are made up of smaller particles called amino acids. In this XXL Nutrition blog, we tell you all about these building blocks of protein!
What are amino acids?
Proteins are made up of chains of amino acids. You can actually think of a protein as a kind of string of beads. The beads are the different amino acids that make up the protein. We distinguish 3 types of amino acids, namely essential, semi-essential and non-essential amino acids. Your body can make the non-essential amino acids itself and is also capable of making the semi-essential amino acids. Only in special cases, such as illness, can your body not produce them. You should always get the essential amino acids from your diet, since your body does not produce them itself.
Proteins differ in structure from carbohydrates and fats. Carbohydrates and fats contain carbon (C), hydrogen (H) and oxygen (O) atoms. Protein additionally contains nitrogen (N) as a building block.
In total, there are 22 different amino acids, 9 of which are essential. The table below shows all the amino acids there are. The amino acid profile varies by food source, so by eating a variety of foods you will get all 22.
Essential Amino Acids | Semi-essential Amino Acids | Non-essential Amino Acids |
---|---|---|
Histidine | Arginine | Alanine |
Isoleucine | Asparagine | Aspartic acid |
Leucine | Glutamine | Cysteine |
Lysine | Glycine | Cystine |
Methionine | Serine | Glutamic acid |
Phenylalanine | Proline | Tyrosine |
Threonine | Hydroxyproline | |
Tryptophan | ||
Valine |
Essential Amino Acids
As mentioned, our body cannot produce these essential amino acids on its own. Therefore, you need to obtain them through your diet. If you don't consume enough of these amino acids, a deficiency may occur, which can negatively affect your body's functioning.
Fortunately, with a varied and protein-rich diet, you can get all the essential amino acids. However, for some groups, like vegetarians and vegans, it can be a bit more challenging. This is because animal proteins, such as meat, eggs, and poultry, are particularly rich in these essential amino acids. Plant-based protein sources that also contain all 9 essential amino acids include soy, tofu, quinoa, and hemp[1].
- Phenylalanine is converted by your body into tyrosine, dopamine, epinephrine, and norepinephrine.
- Histidine is used to produce histamine.
- Isoleucine is one of the BCAAs and plays a role in muscle mass development.
- Leucine is a BCAA (branched-chain amino acid) important for protein synthesis.
- Lysine plays a role in protein synthesis.
- Methionine is a sulfur-containing amino acid used for protein synthesis.
- Threonine is a hydrophilic amino acid and a component of collagen and elastin.
- Tryptophan is a precursor for the production of serotonin and melatonin.
- Valine is the last of the 3 BCAAs and contributes to muscle mass development.
Semi-essential amino acids
Semi-essential amino acids can also be produced by your body. However, in exceptional cases, your body is unable to produce these amino acids in sufficient quantities. This is the case, for example, during illness, pregnancy, or in young children.
For instance, your body may not produce enough arginine when recovering from a serious injury or when it is fighting diseases like cancer. Other semi-essential amino acids, such as glycine and arginine, are insufficiently available during pregnancy. In such cases, it becomes especially important to obtain these amino acids through food (or potentially supplements).
- Arginine is a precursor of nitric oxide.
- Asparagine plays a role in the production and absorption of other amino acids.
- Glutamine is involved in the metabolism of amino acids, carbohydrates, and fats.
- Glycine is produced in the liver and makes up about one-third of the collagen in your body.
- Serine is an amino acid used in protein synthesis.
- Proline is a hydrophobic amino acid involved in collagen formation.
Non-essential amino acids
Non-essential amino acids are produced by your body. Therefore, it is not necessary to obtain these amino acids from your diet or supplements.
- Alanine is an amino acid that is part of almost every protein molecule.
- Aspartic acid is the precursor to aspartate, which is an excitatory neurotransmitter.
- Cysteine is a sulfur-containing amino acid.
- Cystine is an amino acid involved in protein synthesis.
- Glutamic acid, also known as glutamate, is an excitatory neurotransmitter.
- Tyrosine is a hydrophilic amino acid and a precursor for the production of dopamine and thyroid hormones.
- Hydroxyproline is the hydroxylated form of proline and a building block of collagen.
Whey Protein has a complete amino acid profile
By consuming enough protein daily, you get all the essential amino acids. As mentioned, protein-rich products like meat, fish, eggs, poultry, dairy, soy, and tofu are rich in essential amino acids. But did you know that Whey Protein also has a complete amino acid profile?
Whey protein is derived from cow's milk and contains all 9 essential amino acids. This makes a whey protein shake a perfect addition to your diet if you want to easily increase your protein (and amino acid) intake. However, be aware that whey protein powder is not suitable if you're vegan or lactose intolerant.
Amino Acids from Food or Supplements?
To get all the essential amino acids, it’s important to consume enough protein every day from a variety of sources. It’s not strictly necessary to use supplements, as many foods contain a complete amino acid profile. However, in some cases, it might be smart to take a protein shake or a BCAA supplement. Try Clear Whey Isolate – a refreshing protein shake as light as lemonade!
This is especially relevant if you don’t consume animal products. Vegans and, to a lesser extent, vegetarians are at risk of not getting enough essential amino acids. By consuming extra protein and varying your plant-based protein sources, you can avoid this. For convenience, you could also choose to take an amino acid supplement.
Do you eat both animal and plant-based products and follow the recommended daily protein intake? Then you probably won’t need an extra supplement to get the necessary amino acids.
Amino acids are the building blocks of proteins
In this article you have been able to read more about amino acids, the building blocks of proteins. We have tried to answer the question; what are amino acids? Proteins are made up of small particles and they all have a function in our body. We distinguish essential amino acids, semi-essential amino acids and non-essential amino acids. The last two your body can produce itself, the first group you will have to get from your diet. Besides eating protein-rich foods, you can also choose to take a protein shake or BCAA supplement to get more amino acids.
Bronnen
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5188409/