What are the amino acids in Kyotorphin

Amino acids: this is how they regulate our metabolism

Amino acids are found in plant and animal foods.
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Amino acids fulfill numerous functions in the body and regulate our metabolism. Our body can produce some amino acids itself, others we have to take in with food, i.e. food.

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What are Amino Acids?

Amino acids are chemical compounds that form long chains of proteins, i.e. the proteins in our body. Proteins have numerous functions in the organism and occur in every cell, including as building materials for muscles, skin, hair, nails, bones, tendons and other organs.

The proteins, which are important for the immune system, include antibodies, blood clotting factors and enzymes. Hormones and so-called neurotransmitters also consist of amino acids. As messenger substances, they are responsible for metabolic processes and for forwarding nerve stimuli.

As the building blocks of proteins, amino acids have a variety of tasks that are important for health, energy production, growth, development and reproduction. Certain amino acids are also said to support muscle building during exercise and weight loss during diets.

How do amino acids become proteins?

If two amino acids connect via the so-called peptide bond, dipeptides are formed. If a third amino acid is added, one speaks of tripeptides. Some (up to ten) amino acids form oligopeptides, more than ten are called chain-like polypeptides.

Such polypeptides can fold or collapse to form proteins with over 100 or several thousands of amino acids.

How many and which amino acids are there?

Biologists know more than 250 different amino acids, 23 of which are known as proteinogenic amino acids are responsible for building proteins. Due to their chemical structure, 20 of them are called (canonical) standard amino acids. The other non-proteinogenic amino acids also have important functions, but are not part of body proteins.

Essential and non-essential amino acids

Our body can produce eight of the proteinogenic amino acids itself. One speaks of non-essential (or dispensable) amino acids. There are also eight essential (or non-dispensable) amino acids - the body cannot produce them itself and has to take them in through food. There are also conditionally essential amino acids.

What are Conditionally Essential Amino Acids?

Amino acids that are actually non-essential, but become essential in certain life situations, are conditionally essential. For example, the body of healthy adults can produce the amino acid tyrosine itself.

For children, however, the chemical compound is essential because the body's function to produce it is not yet fully developed at a young age. In newborns and premature babies, arginine, cysteine ​​and histidine are also essential at the beginning.

The need for some amino acids can also change during pregnancy or during increased physical activity.


There are also diseases that impair the amino acid metabolism. Affected people then also have to take in non-essential amino acids with their food.

List of known proteinogenic amino acids

Essential amino acids

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

Non-essential amino acids

  • Alanine
  • Asparagine
  • Aspartate
  • Glutamate
  • Glutamine
  • Glycine
  • Proline
  • Serine
  • Arginine (conditionally essential)
  • Histidine (conditionally essential)
  • Cysteine ​​(semi-essential)
  • Tyrosine (semi-essential)

Which foods contain essential amino acids?

Essential amino acids are contained in vegetable and animal protein sources, whereby animal foods often outweigh their content. Chicken eggs, for example, contain all of the essential and semi-essential amino acids that the human body needs. But also meat, fish and dairy products as well as nuts, legumes and soybeans are foods that contain amino acids.

Where do amino acids occur and when do we need them more?

amino acidAverage needPossible increased needOccurrence
Phenylalanineabout 14 mg / kg body weightacute and chronic stress, depression, Parkinson's diseaseTuna, beef, soybeans, peanuts
Isoleucineabout 10 mg / kg body weightwith intensive sports training, physical stress, liver and kidney diseasesPeanuts, salmon, tuna, beef
Tryptophanabout 4-5 mg / kg body weightin competitive athletes, sleep disorders, depressionTuna, spirulina, pumpkin seeds, cashew nuts, walnuts, cheese, veal and beef
Methionineabout 13 mg / kg body weightfor urinary tract diseases, allergies, depressionSalmon, shrimp, turkey breast, hard cheese, soybeans
Leucineabout 14 mg / kg body weightwith intensive sports training, physical stress, liver and kidney diseases, schizophreniaEggs, salmon, tuna, peanuts, beef and veal
Valineabout 10 mg / kg body weightwith intensive sports training, physical stress, liver and kidney diseases, schizophreniaSalmon, tuna, peanuts, beef and veal
Lysineabout 15 mg / kg body weightin the case of a weakened immune system, viral infections, osteoporosis, cardiovascular diseasesFish, parmesan cheese, pork, shrimp
Threonineabout 6-7 mg / kg body weightwith heavy physical exertion, frequent infections, hyperactive nerve reactions, multiple sclerosisPapaya, soybeans, lentils, wheat germ

Effect: what do you need amino acids for?

Amino acids are very important chemical compounds that, due to their different structure, have different tasks. For example, they are responsible for building collagen, the structural protein of bones, connective tissue and skin, as well as for building enzymes, hormones, blood coagulation factors, antibodies and muscles.

Role of the essential amino acids

  • Phenylalanine: Precursor of the hormones adrenaline, noradrenaline, dopamine and thyroxine, has anti-inflammatory effects, formation of melanin

  • Isoleucine: Energy source of the muscles, inhibits the breakdown of protein

  • Tryptophan: Precursor substance for serotonin (sleep-wake rhythm and mood enhancer), liver metabolism, build-up of niacin and tryptamine

  • Methionine: Detoxification function, regeneration of liver and kidney damage, selenium metabolism, development of various amino acids and hormones

  • Leucine: Energy source and structure of the muscles, inhibits the breakdown of protein

  • Valine: Energy source of the muscles, protein build-up and storage, inhibits protein breakdown

  • Lysine: Support of the immune system, has an antiviral effect, formation of enzymes, hormones and antibodies, growth, bone health, tissue repair, stability of the blood vessels

  • Threonine: Growth and energy production, uric acid and protein metabolism, strengthens the immune system and forms antibodies, precursors of the amino acids glycine and serine

Role of the non-essential amino acids

  • Alanine: An important part of the muscles, influences the blood sugar level, the immune system and the liver metabolism

  • Asparagine: Stimulates kidney activity and cleanses the body

  • Aspartate: Participation in the detoxification process; acts as a neurotransmitter, so it is very important for the messenger substances in the brain

  • Glutamate: As a neurotransmitter, it transmits signals between nerve cells

  • Glutamine: Energy generation, an important part of the muscles, supports their regeneration

  • Glycine: Hemoglobin metabolism, so it ensures the transport of oxygen in the blood; involved in the development of muscles, bones, cartilage, tendons, skin and teeth

  • Proline: Regeneration of bone and cartilage inflammation, protects against collagen and joint degradation

  • Serine: Growth, energy production, uric acid and energy metabolism, formation of antibodies

  • Arginine (conditionally essential): Stimulation of cell formation, leucocyte formation, release of growth hormones, insulin and norepinephrine, influences blood circulation and the cardiovascular system

  • Histidine (conditionally essential): Build-up of creatine, so important for energy production in muscles

  • Cysteine ​​(semi-essential): Involved in building hair and nails, building muscle and detoxifying the body

  • Tyrosine (semi-essential): Formation of adrenaline, noradrenaline and dopamine, involved as neurotransmitters in communication between nerve cells

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Lack of amino acids

We have to take in essential amino acids with our food. An unbalanced diet, one-sided diet, stress or competitive sport as well as chronic illnesses can lead to a deficiency in certain amino acids. The need for special amino acids can also increase in newborns, during pregnancy or, for example, after severe injuries.

Non-essential amino acids are just as important as essential amino acids. However, our body normally produces it itself without our conscious involvement. How many semi-essential and non-essential amino acids the body needs or produces depends, among other things, on age, a possible pregnancy and the respective performance requirements.

With a so-called aminogram, a profile of the amino acids in the body, laboratories use a blood sample to assess whether there is a deficiency.

Possible signs of an amino acid deficiency:

  • Listlessness
  • Weakened immune system
  • Difficulty concentrating
  • Inner unrest
  • Digestive problems
  • Depressed moods
  • Difficulty sleeping
  • Drop in performance
  • Joint discomfort
  • Deficits in muscle building

Intake of amino acids

Amino acids regulate numerous metabolic processes in the body, so they are extremely important for our health. In the case of a one-sided diet or if the demands on our performance change, for example in competitive sports, with sustained physical exertion, illness or stress, the need for individual amino acids can change.

Eggs, dairy products, muscle meat and legumes are particularly good sources of amino acids. Some amino acids can also be bought in the form of dietary supplements.

Do not overdose on amino acids

Anyone who overdoses individual amino acids with dietary supplements can, however, trigger an amino acid imbalance in the metabolism and under certain circumstances risk gastrointestinal complaints, excessive strain on the kidneys or other health problems. If you suspect a deficiency, you should therefore not resort to individual preparations yourself, but seek advice from a nutritionist.

Amino acids in sports

The German Nutrition Society (DGE) recommends that amateur and competitive athletes do not take amino acid preparations separately. However, some amino acids may be beneficial for the athlete in appropriate concentrations.

  • Arginine For example, it is intended to improve blood circulation in the muscles, strengthen the immune system and promote wound healing. Nuts, legumes and chicken breast are particularly suitable sources.

  • Cysteine is known to help build muscle mass and improve muscle function. This effect is also used by patients with certain diseases who want to stop a strong muscle breakdown. Whey protein, for example, has a particularly high cysteine ​​content.

  • Isoleucine, leucine and valine support a rapid recovery of the immune system, stabilize the glutamine concentration and can improve muscle metabolism and endurance. The three amino acids are mainly found in tuna, salmon and peanuts.

By the way: products made from “whey protein” are a mixture of amino acids made from the particularly soluble and valuable whey protein.

Do Amino Acids Help You Lose Weight?

In order to permanently lose weight or body fat, a change in diet and exercise are essential. In certain cases, some amino acids can help in exact doses.

For example, the need for leucine, isoleucine and valine can increase with diets or exercise. Our body needs them for muscle metabolism. Good sources are tuna, salmon, and peanuts.

Diets can also be deficient in phenylalanine, tryptophan, and methionine. A particularly suitable source is, for example, the combination of low-fat quark with whole grain.

Caution: Too many proteins in food can put stress on the kidneys. Amino acids in the form of dietary supplements can also be overdosed.

  • Methionine Overdosed can lead to increased excretion of calcium and be a risk factor for cardiovascular diseases.

  • Tryptophan Overdosed can lead to muscle pain and fatigue.

  • In case of overdoses with Phenylalanine headaches, anxiety and high blood pressure can occur.

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