Essential amino acids in human diet are: phenylalanine, methionine, lysine, threonine, valine, leucine, isoleucine, tryptophan. They differ from other classes these compounds for the fact that they must be necessarily introduced in the body through the diet. In addition to BCAAs, arginine and glutamine also have positive effects on the body engaged in sport activities.
Arginine is closely related to the secretion of growth hormone. Growth hormone is important both for muscle building and for muscle repairing. Replenishment of arginine is considered to promote the synthesis of myoproteins. Glutamine, an amino acid distributed abundantly in muscles, helps the synthesis of myoproteins and inhibits their breakdown, as is the case with leucine.
What are essential amino acids?
Essential amino acids are particular amino acids, organic molecules that form proteins. There are three major categories of these compounds:
Essential amino acids: they cannot be synthesized by the body, but they must be obtained through the diet. In adult they are phenylalanine, methionine, lysine, threonine, valine, leucine, isoleucine, tryptophan. During childhood this category includes also arginine, cysteine, histidine and tyrosine.
Non essential or semi-essential amino acids: they can be produced by the body, as alanine, asparagine, glutamic and aspartic acid.
Conditional amino acids: they might become essential in some pathological conditions. Belong to this category arginine, glycinine, tyrosine, serine, proline, glutamine and ornithine.
Every essential amino acid has specific benefits. In particular:
- Phenylalanine: D-phenylalaline is used to treat chronic pain, to relieve symptoms related to Parkinson’s disease. L-phenylalanine instead acts in case of vitiligo, but also depression
- Methionine: it is used to treat chronic urinary infections and in case of kidney stones, because methionine is able to make urine more acid, so that bacteria are unable to survive. It is also used in case of liver diseases as cirrhosis, or heavy metal intoxication.
- Lysine: supplements of lysine are used to treat herpes virus infections, osteoporosis and for the health of hair
- Threonine: this amino acid is particularly known for its purifying properties for liver and kidneys, especially for hepatic steatosis. It can also boost tissue regeneration, stimulating synthesis of collagen and elastin. Other important aspects of threonine are the power on immune system and the prevention of trauma to tendons and muscles.
- Valine: L-valine enhance athletic exercise, helps to treat liver diseases and dyskinesia.
- Leucine: supplements of leucine are used in rare cases, for example by endurance athletes and in bodybuilders, to reduce recovery time and to increase muscles volume.
- Isoleucine: this amino acid is present in many supplements for athletes, because it reduces recovery time in case of intense exercise.
- Tryptophan: supplements of tryptophan are used for insomnia but also in some cases of depression or Obsessive Compulsive Disorders.
Essential amino acids and foods
Foods rich in proteins, and then in amino acids, are especially meat, fish, cheese, milk and some vegetarian foods as soybeans, nuts and seeds. Methionine is found in particular in eggs, milk, nuts, cereal grains, soy proteins and fish. Foods rich in lysine instead are pork, cheese, dairy products, wheat germ, brewer’s yeast. Threonine is found in a great part of legumes and in all types of meat. Valine is present mostly in rye, but also in nuts, milk, chicken, salmon, rice and peas. Leucine is found in particular in nuts, legumes, corn, peanuts, meat and fish. Foods rich of isoleucine are lamb, pork, chicken, cheese, eggs, tuna, nuts, beans. Tryptophan is present in legumes, chocolate, peanuts, diary products, yogurt, seeds and spirulina.
Essential amino acids property
Essential amino acids properties are specific for each kind of amino acid:
- Phenylalanine: it is used by the body to synthesize tyrosine, a conditional amino acid from which are obtained L-dopa, adrenaline, noradrenaline and thyroid hormones.
- Methionine: it is involved in the synthesis of other amino acids, as cysteine, carnitine, taurine and lecithin. Methionine can remove heavy metals from the organs and it’s important for the health of skin, nails and hair.
- Lysine: is a component of collagen, but it is also the precursor of carnitine and niacin. It is able to enhance immune system through antibodies production, it stimulates hormones and enzymes synthesis.
- Threonine: this amino acid is particularly important for nervous and immune functions, and for liver health.
- Valine: it is essential to product many proteins, but also to obtain energy
- Leucine: it is important for the construction of skeletal muscles and for the protein synthesis
- Isoleucine: this amino acid is particularly important for the body because it is involved in the synthesis of hemoglobin and proteins.
- Tryptophan: it is very important for the body because it is the precursor of the neurotransmitter serotonin, melatonin and niacin.
Essential amino acids have a variety of roles in sports nutrition. The major functions of essential amino acids include repairing muscle damage, promoting muscle glycogen resynthesis and preventing sports anemia by increasing the synthesis of oxidative enzymes and mitochondria during exercise. This is all completed by the ability of the amino acids to increase retention of nitrogen that increases muscle mass.
Essential amino acids side effects
Side effects of essential amino acids are not frequent, because they are physiologically present and product by the body. In some case can occur restlessness, anxiety and tachycardia. If they are assumed in excessive amounts, they can cause kidney problems, related to the accumulation on proteins.