Amino acids: building blocks of the body

Veröffentlicht am: October 29, 2024

Sarah Allen

Nutritionist and dietician

The term amino acid is often used in sports and nutritional science.

But what exactly are amino acids and what function do they have in the body?
Which amino acids are essential and how can we get them from our food?

Find out more about the function, relevance and food sources of amino acids.

What are amino acids?
What are the functions of amino acids?
What are proteinogenic amino acids?
What types of amino acids are there?
Which foods contain amino acids?

What are amino acids?

In general, around 270 to 280 different amino acids are known.

These can be divided into proteinogenic and non-proteinogenic acids. Non-proteinogenic amino acids are found in nature but cannot be used to build body proteins.

➤ Did you know that only 20 amino acids are important for the formation of protein in the human body?

These 20 amino acids are proteinogenic acids and form the basis of all proteins.

Organic compounds are often referred to as the building blocks of the body, as they play an important role in the human body.

What are the functions of amino acids?

Their tasks include the maintenance of vital processes, such as the synthesis of hormones and neurotransmitters. They therefore also influence numerous metabolic processes in our body and are able to form different tissues such as organs, muscles, skin and hair. They are also the only natural source from which our body can obtain nitrogen.

A sufficient supply of amino acids can also:

Have a positive effect on weight loss
Positively influence the build-up and maintenance of muscle mass
Increase performance and shorten regeneration phases
Improve sleep and positively influence mood

What are proteinogenic amino acids?

There are a total of 20 different proteinogenic amino acids, all of which are important for human health.

Proteinogenic means that they form the vital proteins. The number and combination of amino acids determines the quality of a protein source.

The acids also have different molecular structures. This means that depending on what our body needs the acids for, the proteins are broken down into their different components.

What types of amino acids are there?

Amino acids differ in the form in which they are formed. In other words, whether the body can produce them itself or whether they have to be ingested through food. The acids are basically divided into three types: essential, semi-essential and non-essential amino acids.

What are essential amino acids and what is their function?

There are a total of eight amino acids that can be assigned to this type. They cannot be formed independently by the body and it is therefore recommended that they are taken in through food.

These amino acids include

Threonine

The main function of threonine is to maintain healthy skin and teeth. It is an important component of tooth enamel, collagen and elastin. It also supports fat metabolism and can have a positive effect on people with digestive disorders, anxiety and mild depression.

Lysine

This acid plays an important role in muscle building. It also contributes to maintaining bone strength and supporting recovery after injuries or operations. It helps to regulate hormones, antibodies and enzymes.

Valine

Valine is important to promote mental focus, muscle coordination and emotional calm. If there is a deficiency of this amino acid, it can lead to sleep problems and have an impact on mental function. Valine is also often used as a supplement for muscle growth, tissue repair and energy.

Leucine

Leucine has a positive effect on the regulation of blood sugar levels. It also supports the growth and repair of muscles and bones, wound healing and the production of growth hormones. A deficiency can lead to skin rashes, hair loss and tiredness.

Isoleucine

Isoleucine supports wound healing, blood sugar regulation, hormone production and the immune system. This amino acid is mainly found in muscle tissue. Older adults can be more susceptible to isoleucine deficiency than younger people. This deficiency can lead to muscle atrophy and tremors.

Phenylalanine

Phenylalanine helps the body to use other amino acids as well as proteins and enzymes. The body converts phenylalanine into tyrosine, which is necessary for certain brain functions.

Tryptophan

Tryptophan is necessary for the proper growth of infants and is a precursor of serotonin and melatonin.

Methionine

The health and flexibility of skin and hair are the two main tasks of methionine. It also makes nails strong and supports the absorption of selenium and zinc.

What are non-essential and semi-essential amino acids?

The acids assigned to this group can normally be formed by the body from other amino acids and are therefore non-essential. This means that, unlike the essential amino acids, they do not have to be ingested through food.

However, if different conditions apply, they may have to be supplied via the food consumed. If this is the case, they are considered semi-essential amino acids.

Factors that can lead to the body no longer being able to produce the amino acids itself include pregnancy, injuries, growth phases and often babies can also be affected.

These amino acids include:

Histidine

Sufficient intake is very important, especially during the growth phase, as otherwise growth retardation and functional disorders can occur.

Arginine

Arginine is needed by the body during sport, stress and illness. In addition to enzymes and messenger substances, it also supports the formation of skin, hair and muscles.

Aspartic acid and asparagine

The proteinogenic amino acid supports the detoxification of the body and promotes the stimulation of kidney production. The result is that asparagine has a blood-purifying and diuretic effect.

Tyrosine

Tyrosine has a positive effect on neurotransmitters and hormone production. This improves the emotional state and promotes creativity and the ability to concentrate.

Cysteine

This amino acid is a major component of creatine which is known as the foundation stone for hair, skin and nails.

Glutamine and glutamic acid

These two amino acids are important for a wide range of functions in the body. On the one hand, they serve as a basic substance for the formation of other amino acids such as arginine, glycine, alanine and proline.

Glycine

This amino acid is particularly present in structural processes in the body. As a result, glycine is also involved in the production of haemoglobin and DNA.

Alanine

If there is a lack of energy in the body, alanine is used as an energy source alongside gluatamine. It is also responsible for the removal of nitrogen during protein breakdown.

Proline

This amino acid, in the form of hydroxyproline, is an important component of collagen. It is therefore important for the structure of bones, skin, tendons and connective tissue.

Serine

Serine is a component of compounds that are found in the nerve cell membrane. It therefore plays an important role in our nervous system.

Which foods contain amino acids?

There are many foods that contain amino acids. Depending on how "complete " the essential acids are, there are more efficient or less valuable sources.

The following list provides an overview of valuable sources of amino acids:

Fish (tuna, salmon, prawns)

Fish and seafood are particularly protein-rich foods, which is why they should be an integral part of a balanced diet. Fish is also an excellent source of the essential amino acids valine, leucine, threonine, lysine and tryptophan. It is particularly easy to digest and the proteins are very readily available to the body.

Beef and chicken

➤ Did you know that beef provides all the amino acids that the body cannot produce itself?

This is also the reason why it has an extremely positive effect on muscle protein synthesis. However, depending on which cut of beef is consumed, it should be noted that the calorie content can vary greatly. Chicken meat offers a lower-calorie option. This consists of approx. 43.2% essential amino acids and contains: phenylalanine, valine, threonine, isoleucine, methionine and leucine. When choosing meat, however, attention should be paid to quality and, if possible, regional products from organic farming should be used.

Soybeans

With 40% protein, soybeans are the absolute front runners among plant-based protein sources. The composition of amino acids in this food is optimal and it contains all the essential acids. In addition, the beans are easily digested, making it particularly efficient for building up the body's own protein.

Nuts

Walnuts, peanuts and cashews, as well as pistachios, pumpkin seeds and chia seeds, contain a number of important amino acids. This makes nuts and nut butters a very efficient source of protein, fat and fiber. The values and the amino acids contained vary depending on the type of nut.

Spirulina

➤ Did you know that spirulina can contain up to 70% protein?

This special algae contains all the essential amino acids and is therefore "complete". This is extremely rare, especially with plant-based protein sources.

Nevertheless, it is important to pay attention to the quality of the spirulina supplement, as the values depend heavily on how good the product is and how it has been processed. Spirulina should be taken dried, in capsule form or in powder form.

Other foods rich in amino acids are peas, spinach, broccoli, milk, eggs, quinoa, oatmeal and lentils.

Conclusion

Amino acids form the basis of all proteins and are known as the building blocks of the body. They are necessary for the maintenance of vital processes and influence our metabolic processes.
It is important to ensure that the essential amino acids are taken in with food, as they cannot be produced by the body itself.
Foods such as beef, fish and nuts can be consumed.
If necessary, the semi-essential acids should also be supplied externally. Babies, growing children, pregnant women and people with injuries in particular may find that the body can no longer produce the amino acids itself.

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Lupatini, A. L., Colla, L. M., Canan, C., & Colla, E. (2017). Potential application of microalga Spirulina platensis as a protein source. Journal of the science of food and agriculture, 97(3), 724–732. doi: 10.1002/jsfa.7987

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