Amino acids
Amino acids are the building blocks of protein, and unlike the two other basic nutrients – sugar and fatty acids, amino acids contain nitrogen – about 16%. Because of the vital functions of these nutrients, great care should be taken by any person concerned about their health, to ensure that sufficient amounts are supplied by the body in either dietary form, or if needed by supplementation.
Amino acids - general information
Protein is needed by every living organism, and next to water, makes up the largest portion of our body weight since it is contained in muscles, organs, hair, etc. The protein used in making up the body is not directly derived from diet, but the dietary protein is broken down into amino acids, and the body then re-constitute these amino acids into the specific proteins needed.
Enzymes and hormones regulating body functions are also proteins. And amino acids are used in most body processes from regulating the way the body works to how the brain functions - They activate and utilize vitamins and other nutrients. Proteins are chains of amino acids linked together, bound together with peptide bonds and there are about 28 amino acids commonly referred to in human health. The liver manufactures about 80% of these amino acids, but the remaining 20% of such amino acids must be supplied directly by diet, and these amino acids are referred to as the essential amino acids.
The functioning of amino acids is interrelated, and a balanced and steady supply of these nutrients is needed to maintain proper body functioning. A dietary shortage of amino acids can impact negatively on your health - just as other stressors, such as trauma, drug use, age, infections etc. When the body synthesizes protein, ammonia is formed in the liver as a waste product, and too large amounts of protein into the diet can result in too much ammonia being formed, and in so doing placing extra stress on the liver and kidneys to flush it out the body.
Amino acid supplements come in various forms but can essentially be divided in three types of products – either derived from animal protein, yeast or vegetable protein. Most amino acids can be produced in two forms, except for glycine, that is either a D or L form.
These letters stands for the way in which the amino acid spiral is wound up - D is for the right wound type and L for the mirror left winding amino acid. Human amino acid is the L type and for this reason many people prefer to use supplements containing the L type amino acid. Amino acid supplementation information Free form amino acids are the ones immediately absorbed into the body and need no digestion at all. When taking an amino acid supplement it is best to have vitamin c (ascorbic acid) as well as vitamin B6 present at the same time for best absorption. But like all things, use it as prescribed, and with common sense, as very high doses of aspartic acid, glutamic acid, homocysteine, serine and tryptophan could form toxic levels in the body, and in so doing cause damage.
These essential amino acids are:
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To view detailed information on the specific amino acid click the hyperlink:
Branched Chain Amino Acids
Histidine
Isoleucine
Leucine
Lysine
Methionine
Phenylalanine
Threonine
Tryptophan
Valine
The 80% or so others that are manufactured by the liver, and which are classed as "nonessential" amino acids are:
To view detailed information on the specific amino acid click the hyperlink:
Alanine
Arginine
Asparagine
Aspartic Acid
Carnitine
Citrulline
Cysteine
Cystine
Gamma-Aminobutyric Acid
Glutamic Acid
Glutamine
Glutathione
Glycine
Hydroxyproline
NAC - N-acetyl cysteine
Ornithine
Proline
Serine
Taurine
Tyrosine
Alanine Amino Acid
Alanine is a non-essential amino acid and is used by the body to build protein and was first isolated in 1879. The alpha-carbon in alanine is substituted with a levorotatory (l)-methyl group, making it one of the simplest amino acids with respect to molecular structure and is one of the most widely used in protein construction.
Importance of Alanine
It is needed for the metabolism of glucose and tryptophan and beta-alanine is a constituent of vitamin B5 (pantothenic acid) as well as coenzyme A. Individuals suffering from Epstein Barr (also sometimes referred to as glandular fever) as well as chronic fatigue syndrome, have been linked to excessively high levels of alanine while having low levels of tyrosine and phenylalanine. People on a very low protein diet, could be at risk of a deficiency.
Deficiency of Alanine None known.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Most individuals do not need to supplement with alanine since it is well provided for in the diet, and can be synthesized from pyruvic acid (formed in the breakdown of carbohydrates).
Risks of Toxicity and symptoms of high intake
Alanine does not have many side effects, but individuals with kidney or liver disease should not consume high intakes of amino acids without consulting a health care professional.
Alanine can be found in the following food sources
Meat, poultry, fish, eggs, dairy products and avocado
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Arginine Amino Acid
Arginine is a non-essential amino acid and is abundant in protamines and histones – both proteins associated with nucleic. Newborn infants may produce this amino acid too slowly and for them arginine is seen as an essential amino acid. Arginine pyroglutamate, in addition to having cognitive enhancing effects, is an excellent growth hormone releaser because it is carried more efficiently across the blood-brain barrier than arginine alone. In Italy, this form of amino acid is used to treat senility, mental retardation, and alcoholism. Arginine pyroglutamate is an arginine molecule combined with a pyroglutamate molecule. Arginine alone does not produce cognitive enhancing effects. This nutrient is gaining popularity as a non-prescription treatment for high cholesterol as animal studies and preliminary studies in humans suggest that it may improve coronary blood flow and lower cholesterol levels with its antioxidant property, and helping to keep blood-vessel tissue elastic.
Importance of Arginine
It is extremely useful in enhancing the immune system, and it increases the size and activity of the thymus gland, which is responsible for manufacturing T lymphocytes – otherwise known as T-cells, which assist the immune system. Because of this reason it is an important nutrient for people suffering from AIDS and other malignant diseases which suppress the immune system. In the pancreas it is needed to release insulin and in the pituitary gland it is a component of human growth hormone, and is used in sexual stimulants. Some individuals experience longer and more intense orgasms when their intake of arginine is increased. It is also important in liver health and assists in neutralizing ammonia in the liver, while it is also involved in the skin and connective tissue – making it important in healing and repair of tissue as well as the formation of collagen and building of new bone and tendons. Arginine is found in seminal fluid and L-arginine is used in the treatment of male sexual health and has been used in the treatment of sterility. It is required in muscle metabolism – maintaining the nitrogen balance, and helping with weight control since it facilitates the increase of muscle mass, while reducing body fat.
Deficiency of Arginine
Rare – but signs may include impaired insulin production as well as possible hair loss.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Risks of Toxicity and symptoms of high intake
Rare, but symptoms of massive dosages may include skin thickening and coarsening of the skin, weakness, diarrhea, nausea, as well as increasing the activity of some viruses. For this reason people suffering from herpes should avoid high dosage. Pregnant and lactating women and people suffering from schizophrenia should also avoid high dosage.
Arginine can be found in the following food sources
Whole-wheat, nuts, seeds, peanuts, brown rice, popcorn, soy, raisins, chocolate, carob
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Asparagine Amino Acid
Asparagine is a non-essential amino acid and is closely related to aspartic acid, and can be manufactured from this nutrient and was first isolated in 1932 from asparagus and is also widely available in plant protein, but a great volume of information is not available.
Importance of Asparagine
It is needed by the nervous system to maintain equilibrium and is also needed for amino acid transformation from one form to the other that is achieved in the liver.
Deficiency of Asparagine
None known.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Risks of Toxicity and symptoms of high intake
None reported.
Asparagine can be found in the following food sources
It is found in dairy, beef, poultry and eggs.
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Aspartic Acid Amino
Aspartic acid is a non-essential amino acid and is found in abundance in plant proteins, especially in sprouting seeds but can be manufactured in the body from oxaloacetic acid. Aspartic acid, as well as glutamic acid, is the only amino acid that has a negatively charged carboxylate group on the side chain.
Importance of Aspartic Acid
It is of a paramount importance in the metabolism during construction of other amino acids and bio-chemicals in the citric acid cycle. Among the bio-chemicals that are synthesized from aspartic acid are asparagine, arginine, lysine, methionine, threonine, isoleucine, and several nucleotides. It is needed for stamina, brain and neural health and assists the liver by removing excess ammonia and other toxins from the bloodstream. It is also very important in the functioning of RNA, DNA, as well as the production of immunoglobulin and antibody synthesis.
Deficiency of Aspartic Acid
Symptoms may include fatigue and depression.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Risks of Toxicity and symptoms of high intake
None reported.
Aspartic Acid can be found in the following food sources
Dairy products, beef, poultry, sprouting seeds
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Branched Chain Amino Acids
Branched-chain amino acids (BCAA) include leucine, isoleucine as well as valine.
Importance of Branched chain amino acids
This group of amino acids help to maintain muscle tissue; they also are needed during times of physical stress and intense exercise.
Deficiency of branched chain amino acids
See leucine, isoleucine and valine
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
A diet that includes animal protein provides an adequate amount of BCAA for most people.
Athletes involved in intense training may often take 5 grams of leucine, 4 grams of valine, and 2 grams of isoleucine per day to prevent muscle loss and increase muscle gain.
Risks of Toxicity and symptoms of high intake
No side effects have been reported with the use of BCAA. A high intake of BCAA are simply converted into other amino acids or used as energy.
Branched chain amino acids can be found in the following food sources
Dairy, red meat, protein and eggs
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Carnitine
Carnitine is really not an amino acid, but because of the close structural sameness, it is normally classed with amino acids, and is also known as vitamin BT. It is available as D-carnitine, L-carnitine, DL-carnitine as well as acetyl-L-carnitine, but with L-carnitine being the most popular type. L-Carnitine is synthesized from the essential amino acids lysine and methionine, but enough vitamin B1 (thiamine) and B6 (pyridoxine) must be available.
Importance of Carnitine
Unlike a true amino acid, it is not used in protein synthesis or as neurotransmitter, but is needed for long-chain fatty acid transport and is needed for entry of these long-chain fatty acids into the mitochondria of the cell, as well as for the removal of short-chain organic acids from the mitochondria, which frees the intra-mitochondrial coenzyme. It is therefore important for the energy supply within the cell, as well as muscles, assists in preventing fatty build-up in areas such as the heart, liver, and skeletal muscles. It may also reduce the risk of poor fat metabolism in diabetes, alcohol-induced fatty liver as well as the risk of heart problems. Carnitine has also been shown to improve the antioxidant effect of vitamin C as well as E.
Deficiency of Carnitine
Primarily, carnitine deficiency occurs because of a genetic defect preventing carnitine transport and a deficiency may result in confusion, heart pain, muscular weakness as well as obesity.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Consult your medical professional regarding this matter. Men normally require more carnitine than women, because of heavier body mass.
Risks of Toxicity and symptoms of high intake
None known but supplements in excess of 3,000 mg (19 mmol) of carnitine per day may cause diarrhea and/or "fish odor" syndrome.
Carnitine can be found in the following food sources
Red meat, fish, chicken and milk
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Citrulline Amino Acid
Citrulline is found in high concentration in the liver. Citrulline is not a component of any major proteins or enzymes.
Importance of Citrulline
The amino acid citrulline is needed to detoxify the liver from ammonia, which is a waste product of the body from oxidation. Citrulline promotes energy and assists with the immune system. Citrulline amino acid is formed in the urea cycle by the addition of carbon dioxide and ammonia to ornithine. It is then combined with aspartic acid to form arginosuccinic acid, which later is metabolised into the amino acid arginine.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
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Cysteine Amino Acid
Cysteine is sulphur containing non-essential amino acid and is closely related to cystine, as cystine consists of two cysteine molecules joined together. It is an unstable nutrient and easily converts to cystine, but this does not cause any problems, since both can convert into the other – as required by the body.
Importance of Cysteine
Your skin, as well as detoxification of your body, requires cysteine. It is found in beta-keratin, the main protein in nails, skin as well as hair. It not only is important in collagen production but also assists in skin elasticity and texture. Cysteine is also required in the manufacture of the amino acid taurine and is a component of the antioxidant gluthione. It is useful to detoxify the body from harmful toxins and help protect the brain and liver from damage from alcohol, drugs etc. It has also been found that it may help in strengthening the protective lining of the stomach as well as intestines, which may help prevent damage caused by aspirin and similar drugs. Cysteine is also critical to the metabolism of a number of essential biochemicals including coenzyme A, heparin, biotin, lipoid acid, and glutathione. People suffering from AIDS/HIV may benefit from cysteine in proper amounts, as low levels are normally reported in people with this problem.
Deficiency of Cysteine
No deficiencies have been reported.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
General dosage is not known but as supplement cysteine is used at 200 mg two to three times per day.
Risks of Toxicity and symptoms of high intake
None known, but damage to nerve cells in rats has been reported in very high dosage, and research data is still being waited upon. People suffering from diabetes and cystinuria should be careful of cysteine supplements.
People suffering from AIDS/HIV may benefit from cysteine in proper amounts, as low levels are normally reported in people with this problem.
Cysteine can be found in the following food sources
Poultry, wheat, broccoli, eggs, garlic, onions and red peppers
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Cystine Amino Acid
Cystine is a crystalline, sulphur-containing amino acid, formed from two molecules of the amino acid cysteine. It can be converted to cysteine by reduction it is particularly abundant in skeletal and connective tissues, hair and digestive enzymes. The steps followed in the formation of cystine and cysteine, is from methionine to cystathionine and then to cysteine to cystine
Importance of Cystine
Needed for proper vitamin B6 utilization and is also helpful in the healing of burns and wounds, breaking down mucus deposits in illnesses such as bronchitis as well as cystic fibrosis. Cysteine also aids in the supply of insulin to the pancreas, which is required for the assimilation of sugars and starches. It increases the level of glutathione in the lungs, liver, kidneys and bone marrow, and this may have an anti-aging effect on the body by reducing age-spots etc. It has been shown as a detoxification agent to protect the body against damage of alcohol and cigarette smoking, and may be effective in preventing hangovers, as well as preventing liver and brain damage.
Deficiency of Cystine
In chronic diseases it appears that the formation of cysteine from methionine is prevented, resulting in a deficiency.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Risks of Toxicity and symptoms of high intake
People suffering from diabetes should be careful when taking supplementation, as it could inactivate insulin
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GABA Amino Acid
GABA is the abbreviation for gamma-aminobutyric acid, is the product of a biochemical decarboxylation reaction of glutamic acid by the vitamin pyridoxal, as well as from decarboxylase (GAD).
Importance of GABA
GABA is needed as an inhibitory neurotransmitter to block the transmission of an impulse from one cell to another in the central nervous system, which prevents over-firing of the nerve cells. It is also needed for brain metabolism and to treat both epilepsy and hypertension where it is thought to induce tranquility in individuals who have a high activity of manic behavior and acute agitation. In combination with inositol and nicotinamide it helps with blocking anxiety and stress related impulses from reaching the motor centers of the brain. Gamma-Aminobutyric Acid can be used to calm an individual, much like tranquilizers, but without the possibility of addiction. It is sometimes used as sexual a stimulant because of its relaxing capabilities, as well as with prostate problems, since it also assists with the release of sex hormones.
Deficiency of GABA
It has been suggested that a shortage of GABA may cause panic attacks, since an intake of tranquilizers can increase the level of GABA in the body. GABA may also be effective in treating PMS in women.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Dosage has not been established
Risks of Toxicity and symptoms of high intake
Toxic levels have not been established, but very high intake of GABA may cause anxiety, tingling of extremities, shortness of breath as well as a numb feeling around the mouth.
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Glutamic Acid
Glutamic acid, a non-essential amino acid and is synthesized from a number of amino acids including ornithine and arginine.
Importance of Glutamic Acid
An important excitatory neurotransmitter, and glutamic acid is also important in the metabolism of sugars and fats. It helps with the transportation of potassium across the blood-brain barrier, although itself does not pass this barrier that easily. It also shows promise in the future treatment of neurological conditions, ulcers, hypoglycemic come, muscular dystrophy, epilepsy, Parkinson's, and mental retardation. Glutamic acid can be used as fuel in the brain, and can attach itself to nitrogen atoms in the process of forming glutamine, and this action also detoxifies the body of ammonia. This action is the only way in which the brain can be detoxified from ammonia. The fluid produced by the prostate gland also contains amounts of glutamic acid, and could play a role in the normal function of the prostate.
Deficiency of Glutamic Acid
None known.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Risks of Toxicity and symptoms of high intake
High dosages of glutamic acid could include symptoms such as headaches and neurological problems. Although no major side effects are reported on supplementation of this nutrient, people with kidney or liver disease should not consume high intakes of amino acids without first consulting a medical professional. People suffering from personality disorders as well as child behaviour disorders may find benefit from this nutrient
Glutamic Acid can be found in the following food sources
Meat, poultry, fish, eggs, and dairy products, as well as some protein-rich plant foods.
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Glutamine Amino Acid
Glutamine is a non-essential amino acid and is found in large amounts in the muscles of the body, and since it easily pass through the blood-brain barrier, it is also known as a superb brain fuel, and some people refer to it as a “smart-vitamin” – although it is in actual fact no vitamin at all.
Importance of Glutamine
It is converted to glutamic acid in the brain, which is essential for cerebral functions, and increases the amount of GABA (gamma-aminobutyric acid), which is needed for brain functioning and mental activity. It is used in the muscles for the synthesis of muscle proteins, and is of use for the treatment of wasting muscles after illness or post-operative care.
Although the body requires nitrogen, free nitrogen in the body can be harmful since it forms ammonia – especially toxic to the brain. The liver normally converts ammonia to urea, excreted in the urine – but glutamic acid attaches itself to nitrogen and forms glutamic acid, while removing ammonia from the brain. It further needed in the body to balance the acid/alkaline level and is also the basis or building blocks of RNA and DNA. It serves as a source of fuel for cells lining the intestines and it is also used by white blood cells and is important for immune function. Individuals suffering from arthritis, fibrosis, connective tissue disease, peptic ulcers, ulcerative colitis, as well as epilepsy, fatigue, impotence and senility may find benefit from an increase of this nutrient, as well as individuals busy with alcohol abuse withdrawal and individuals living with HIV.
Deficiency of Glutamine
Deficiency of this nutrient is rare, since it can be manufactured by the body but deficiencies can develop during periods of fasting, starvation, strict dieting, cirrhosis, and weight loss associated with HIV/AIDS and cancer.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Risks of Toxicity and symptoms of high intake
No clear toxicity has emerged in glutamine studies, but it should not be taken by individuals suffering from liver or kidney problems.
Glutamine can be found in the following food sources
Fish, meat, beans, and dairy as well as in vegetables such as raw parsley and spinach
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Glutathione Amino Acid
Glutathione is actually a tri-peptide made up the amino acids gamma-glutamic acid, cysteine, and glycine and is also known as gamma-glutamylcysteinylglycine or GSH. It is as such not an amino acid, but because of its close relationship to amino acids, is dealt with here. It is found in the largest concentrations in the liver.
Importance of Glutathione
A powerful antioxidant and detoxifies the harmful compounds in the liver, where it is then excreted through the bile. The liver also excretes glutathione directly into the bloodstream where it is used to help maintain the integrity of red blood cells, as well as protecting white blood cells. Glutathione is also found in the lungs and intestinal tract where it assists in carbohydrate metabolism as well as breaking down oxidized fats. It is also used to prevent oxidative stress in most cells and helps to trap free radicals that can damage DNA and RNA. GSH also plays major roles in drug metabolism, calcium metabolism, the gamma-glutamyl cycle, blood platelet and membrane functions.
Deficiency of Glutathione
A deficiency of gluthione is first noticed in the nervous system with a lack of co-ordination, tremors, mental disorders, and body balance, all caused by lesions in the brain.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
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Glycine Amino Acid
Glycine is a sweet tasting, non-essential amino acid this nonessential nutrient can be manufactured from serine and threonine, so dietary intake is not essential.
Importance of Glycine
It is neede to build protein in the body and synthesis of nucleic acids, the construction of RNA as well as DNA, bile acids and other amino acids in the body. It is further found to be useful in aiding the absorption of calcium in the body. It helps in retarding degeneration of muscles since it helps to supply extra creatine in the body. It is also found in fairly large amounts in the prostate fluid and may for this reason be important in prostate health. The glycine amino acid is also used by the nervous system and its function as an inhibitory neurotransmitter, which makes it important to help prevent epileptic seizures, and it is also used in the treatment of manic depression and hyperactivity.
Deficiency of Glycine
Deficiency of glycine Few people are glycine deficient, in part because the body makes its own supply of the non-essential amino acids, and is abundant in food sources.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Risks of Toxicity and symptoms of high intake
No clear toxicity has emerged from glycine studies, however individuals with kidney or liver disease should not consume high intakes of amino acids without consulting a health care professional
Glycine can be found in the following food sources
Fish, meat, beans, and dairy products
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Histidine Amino Acid
Histidine is an essential amino acid, manufactured in sufficient quantities in adults, but children may at some time have a shortage of this important vitamin. It is one of the basic (reference to pH factor) amino acids due to its aromatic nitrogen-heterocyclic imidazole side chain. This amino acid is metabolized into the neurotransmitter histamine and the set of genes that produce the enzymes responsible for histidine synthesis.
Importance of Histidine
Histidine is also a precursor of histamine, a compound released by immune system cells during an allergic reaction. It is needed for growth and for the repair of tissue, as well as the maintenance of the myelin sheaths that act as protector for nerve cells. It is further required for the manufacture of both red and white blood cells, and helps to protect the body from damage caused by radiation and in removing heavy metals from the body. In the stomach, histidine is also helpful in producing gastric juices, and people with a shortage of gastric juices or suffering from indigestion. It is reported that an increase in the intake of this nutrient helps with the lengthening of orgasms and also more intense sexual enjoyment. Histidine is also used for sexual arousal, functioning and enjoyment Histidinemia is an inborn error of the metabolism of histidine due to a deficiency of the enzyme histidase, where high levels of histidine are found in the blood and urine, and may manifest in speech disorders and mental retardation.
Deficiency of Histidine
None known,
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Some individuals take 1,000 mg of histidine two to three times per day in capsule or tablet form but it is best to work out the dosage requirements as 8-10 mg per day per kilogram of body weight.
Risks of Toxicity and symptoms of high intake
There are no reported side effects with histidine, very high levels of histidine could lead to stress and mental disorders such as anxiety and individuals with schizophrenia have been found to have high levels of histidine. People suffering from schizophrenia or bipolar (manic) depression should not take a histidine supplement without the approval of their medical professional.
Histidine can be found in the following food sources
Dairy, meat, poultry and fish are good sources of histidine as well as rice, wheat and rye.
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Hydroxyproline Amino Acid
Hydroxyproline can be synthesized in the body, making it a non-essential amino acid and is used nearly exclusively in structural proteins including collagen and connective tissue. Not much is known about this nutrient.
This amino acid is not incorporated into collagen during biosynthesis at the ribosome, but is formed from proline by a post-translational modification by an enzymatic hydroxylation reaction. Non-hydroxylated collagen is commonly termed pro-collagen. Excretion of abnormal quantities of hydroxyproline is a symptom of the connective-tissue disease called Marfan's syndrome.
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Isoleucine Amino Acid
Isoleucine is an essential amino acid and is part of the three "branched chain amino acids" (BCAA) - the other two being leucine and valine. This amino acid cannot be manufactured in the body, and needs to be supplied in the diet.
Importance of Isoleucine
Isoleucine, together with the other two branched-chain-amino-acids promote muscle recovery after physical exercise and on its own it is needed for the formation of haemoglobin as well as assisting with regulation of blood sugar levels as well as energy levels. It is also involved in blood-clot formation. People involved with strenuous athletic activity under extreme pressure and high altitude may benefit from supplementation of this nutrient.
Deficiency of Isoleucine
Deficiency of isoleucine is only found in people deficient in dietary protein but symptoms may include headaches, dizziness, fatigue, depression, confusion as well as irritability. Symptoms of deficiency may mimic the symptoms of hypoglycemia. This nutrient has also been found to be deficient in people with mental and physical disorders, but more research is required on this.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Most people ingest enough isoleucine from their diet, although some individuals do supplement their diet with about 650 - 700 mg of isoleucine per day (based on a 70 kg body), or worked out to 10 - 12 mg per kg of body weight per day.
Risks of Toxicity and symptoms of high intake
Consuming higher amounts of isoleucine is not associated with any health risks for most people but those with kidney or liver disease should not consume high intakes of amino acids without medical advise. People ingesting higher amounts of isoleucine report elevated urination.
Isoleucine can be found in the following food sources
Almonds, cashews, chicken, eggs, fish, lentils, liver, meat etc
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Leucine Amino Acid
Leucine is an essential amino acid, which cannot be manufactured in the body and is part of the three branched-chain-amino-acids. Supplements and protein powders that contain leucine are used extensively by bodybuilders and other athletes to promote muscle recovery, although it has not produced significant changes in body composition.
Importance of Leucine
Leucine helps with the regulation of blood-sugar levels, the growth and repair of muscle tissue (such as bones, skin and muscles), growth hormone production, wound healing as well as energy regulation. It can assist to prevent the breakdown of muscle proteins that sometimes occur after trauma or severe stress. It can also be beneficial for individuals with phenylketonuria - a condition in which the body cannot metabolize the amino acid phenylalanine
Deficiency of Leucine
Deficiency of this nutrient is rare, since all protein foods contains it, but vegans and vegetarians without adequate protein sources may suffer from a deficiency. Hypoglycemia symptoms may appear if the diet is deficient and may include dizziness, fatigue, headaches, irritability etc.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
The daily dosage of leucine is about 16 mg per kilogram of body weight per day - which would translate to about 1120 mg for a 70 kg male.
Risks of Toxicity and symptoms of high intake
Consistent evidence of toxicity has not been linked to leucine supplements. A high intake of leucine could contribute to pellagra as well as increase the amount of ammonia present in the body.
leucine can be found in the following food sources
Brown rice, beans, nuts and whole wheat
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Lysine Amino Acid
Lysine is an essential amino acid and is a basic building block of all protein.
Importance of Lysine
It is needed for growth and bone development in children, assists in calcium absorption and maintaining the correct nitrogen balance in the body and maintaining lean body mass. Furthermore it is needed to produce antibodies, hormones, enzymes, collagen formation as well as repair of tissue. As it helps with the building of muscle protein, it is useful for patients recovering from injuries and recovery after operations, and there might be use in lysine to help maintain healthy blood vessels. Athletes and burn patients and individuals suffering from herpes and cold sores may benefit from an increase of lysine. Older people could also require more lysine, as one study found older men required more of this nutrient than younger men.
Deficiency of Lysine
Deficiency of lysine is rare, since it is found in so many protein foods, the symptoms may include anaemia, enzyme disorders, lack of energy, hair loss, bloodshot eyes, weight loss and retarded growth as well as reproductive problems, poor appetite and poor concentration. Individuals on a vegetarian diet, using grains as their only source of protein are often deficient in this nutrient.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
The daily dosage of lysine is about 12 mg per kilogram of body weight per day - which would translate to about 840 mg for a 70 kg male. Pregnant or breast feeding mothers, as well as patients with liver or kidney problems, must first consult a health professional before taking lysine supplements.
Risks of Toxicity and symptoms of high intake
Toxicity has not been determined but animals fed high amounts of lysine, have shown a tendency to gallstones as well as elevated cholesterol - but these tendencies have not been proven in humans. Diarrhea and stomach cramps may be indicative in high dosage, but these are not consistent symptoms.
Lysine can be found in the following food sources
Cheese, eggs, lime beans, potatoes, milk, meat and brewer's yeast.
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Methionine Amino Acid
Methionine is a sulfur containing essential amino acid and was first isolated in 1922 from casein and belongs to a group of compounds called lipotropics - the others in this group include choline, inositol, and betaine. It is important in the process of methylation where methyl is added to compounds as well as being a precursor to the amino acids cystine and cysteine.
Importance of Methionine
Methionine assists in the breakdown of fats and thereby prevents the build-up of fat in the arteries, as well as assisting with the digestive system and removing heavy metals from the body since it can be converted to cysteine, which is a precursor to gluthione, which is of prime importance in detoxifying the liver. The amino acid methionine is also a good antioxidant as the sulphur it supplies inactivates free radicals. It can also be used to treat depression, arthritis pain as well as chronic liver disease - although these claims are still under investigation. Some studies have also indicated that methionine might improve memory recall. It is also one of the three amino acids needed by the body to manufacture creatine monohydrate, a compound essential for energy production and muscle building. Individuals with liver problems, pancreatitis, HIV/AIDS as well as Parkinson's disease may consider obtaining more methionine, after consultation with their health professional, and older people may also benefit from a slightly higher intake of this nutrient. Women on birth control pills could also look at this nutrient, since it promotes the excretion of estrogen. Individuals suffering from schizophrenia could investigate taking extra methionine since it reduces the level of histidine in the body, a level normally higher in people suffering from schizophrenia.
Deficiency of Methionine
Severe deficiency may manifest in dementia, while lesser deficiencies may be known by symptoms like fatty liver, slow growth, weakness, water retention and skin lesions.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
The daily dosage of leucine is about 12 mg per kilogram of body weight per day - which would translate to about 840 mg for a 70 kg male.
Risks of Toxicity and symptoms of high intake
It theorized that a high intake of methionine, in the presence of B vitamin deficiencies, may increase the risk for arteriosclerosis (hardening of the arteries) by increasing blood levels of cholesterol and a compound called homocysteine; and that excessive methionine intake, with
Methionine can be found in the following food sources
Fish, beans, eggs, garlic, lentils, onions, yoghurt and seeds
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NAC Amino Acid (n-acetyl cysteine)
NAC - N-acetyl cysteine (NAC) is an altered form of the amino acid cysteine, which is commonly found in food and synthesized by the body
Importance of NAC
NAC may assist to break down mucus and used in the treatment of bronchitis - for this reason it is used as an inhalant in hospitals in the treatment of bronchitis. It assists the body in synthesizing glutathione and helps to protect the body from acetaminophen (the ingredient in Tylenol).
Deficiency of NAC
Not yet determined.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Dosage is not known but 250-1500 mg per day is used.
Risks of Toxicity and symptoms of high intake
Toxicity has not been determined, but may increase the amount of zinc excreted in the urine and for this reason it may be a good idea to use zinc and copper supplements if using N-acetyl cysteine (NAC) for extended periods.
NAC can be found in the following food sources
Cysteine, the amino acid from which NAC is derived, is found in most high-protein foods.
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Ornithine Amino Acid
Ornithine is a non-essential amino acid and is manufactured by the body, the amino acid, arginine, is metabolized during urea production and is required by the body as it acts as a precursor of citrulline, proline and glutamic acid.
Importance of Ornithine
Ornithine is important since it induce the release of growth hormone in the body, which in turn helps with fat metabolism. It is further required for a properly functioning immune system and liver and assists in ammonia detoxification and liver rejuvenation. It is also of use in healing and repairing skin and tissue and is found in both these body parts.
Deficiency of Ornithine
Since the body can produce ornithine, a deficiency of this non-essential amino acid is rare.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
In human research involving ornithine, several grams are typically used per day, sometimes combined with arginine.
Risks of Toxicity and symptoms of high intake
There are no reported side effects from the use of ornithine, but children, pregnant or nursing mothers, or anybody suffering from schizophrenia should NOT take L-ornithine.
Ornithine can be found in the following food sources
Meat, fish, dairy, and eggs
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Phenylalanine Amino Acid
Phenylalanine is an essential amino acid that is also one of the aromatic amino acids that exhibit ultraviolet radiation absorption properties and is the most commonly found aromatic amino acid. It can be converted in the body to tyrosine, which in turn is used to synthesize two important neurotransmitters - dopamine and norepinephrine. It is available in three different forms - L-, D- and DL-. The L- form is the most common and the type in which it is incorporated into the body's proteins. The D- form acts as a painkiller and the DL- a combination of the two.
Importance of Phenylalanine
It is needed in elevating the mood since it is so closely involved with the nervous system, as well as help with memory and learning and has been used as an appetite suppressant.
People suffering from Parkinson's disease It is DLPA (or the D- or L-form alone) is used to treat depression and the D form may also be helpful in the treatment of Parkinson's disease and chronic pain in both osteo-arthritis and rheumatoid arthritis with mixed results Increases blood levels of norepinephrine, epinephrine and dopamine - all three required for neurotransmission.
Deficiency of Phenylalanine
Deficiency is rare but symptoms may include lethargy, edema, weakness, skin lesions as well as liver damage and slow growth. A deficiency in diet would only occur with an extremely low protein intake.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Pregnant women, people suffering from anxiety attacks, high blood pressure, diabetes and phenylketonuria, should NOT take it. DLPA supplements will interact with certain anti-depressants or stimulants. Individuals must consult a medical professional. The daily dosage is unknown but supplements are taken at about 14 mg per kilogram of body weight per day - which would translate to about 980 mg for a 70 kg male, but since it has powerful mood altering effects, only to be used under medical supervision.
Risks of Toxicity and symptoms of high intake
Toxicity is rare in dietary intake but large amounts in supplement form will play havoc with blood pressure and cause headaches, nausea and heartburn. Large amounts of this nutrient may also cause nerve damage. Some individuals cannot metabolise phenylalanine and should not take supplementation of this amino acid.
Phenylalanine can be found in the following food sources
It is contained in most protein rich foods but good sources are found in dairy products, almonds, avocados, lima beans, peanuts and seeds.
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Proline Amino Acid
Proline was first isolated from casein in 1901, and unlike any of the other amino acids it is readily soluble in alcohol. It is a nonessential amino acid and can be synthesized from glutamic acid and does not require dietary sources. As information is very limited on this nutrient, our page is also very short.
Importance of Proline
Proline improves skin texture and aids collagen formation and helps contain the loss of collagen during aging. Collagen in the skin contains hydroxyproline and hydroxylysine, which is formed from proline and lysine, in which ascorbic acid seems to be important in this conversion. Collagen contains about 15 % proline. It is also thought to be important in the maintenance of muscles, joints and tendons. According to the current information available it would be recommended that an ample supply of vitamin C (ascorbic acid) be present to maximize the efficiency of proline.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Proline can be found in the following food sources
Meat sources.
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Serine Amino Acid
Serine is a nonessential amino acid and can be synthesized in the body from glycine.
Importance of Serine
Serine is needed for the metabolism of fat, tissue growth and the immune system as it assists in the production of immunoglobulins and antibodies. Some derivatives (e.g. ethanolamine) are also important components of the phospholipids found in biological membranes. It is a constituent of brain proteins and nerve coverings and is also important in the formation of cell membranes, involved in the metabolism of purines and pyrimidines, and muscle synthesis. It is also used in cosmetics as a skin moisturizer.
Risks of Toxicity and symptoms of high intake
Although toxicity has not been established it has been found that very elevated serine levels may cause immune suppression and psychological symptoms as in cerebral allergies.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Serine can be found in the following food sources
Meats and dairy products, wheat gluten, peanuts as well as soy products
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Taurine Amino Acid
Taurine is a non-essential amino acid and is found in high concentrations in the white blood cells, skeletal muscles, central nervous system as well as the heart muscles. In adults, but not children, this nutrient can be manufactured from methionine in the body and from cysteine in the liver, but vitamin B6 must be present.
Importance of Taurine
It is a key ingredient of bile, which in turn is needed for fat digestion, absorption of fat-soluble vitamins as well as the control of cholesterol serum levels in the body. (It is incorporated in the bile acid chenodeoxychloic acid, which emulsify the dietary fats) This nutrient is also used in the proper use of potassium, calcium as well as sodium in the body, and for maintaining cell membrane integrity. It is thought to be helpful with anxiety, hyperactivity, poor brain function and epilepsy as well as hydrating the brain. Taurine, together with zinc is also required for proper eye health and vision. Vegetarians who consume no eggs or dairy products ingest virtually no taurine through their diets, but normally have enough since the body can manufacture the requirements. Children with Down's syndrome may benefit from taurine, and women being treated for breast cancer as well as people with metabolic disorders, since metabolic disorders can cause loss of this nutrient via urine. Diabetics may also benefit from this nutrient, since this disease increase the need for this nutrient.
Deficiency of Taurine
A deficiency may impair vision and problems with fat metabolism may appear, and a theory exists that it may also be involved in epilepsy developing.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
No dosage has been established, but people who take supplements normally take 2 grams, three times per day.
Risks of Toxicity and symptoms of high intake
No toxicity has been determined and most people would not require a supplement and even small children derive enough of it through human milk, or infant formulas.
Taurine can be found in the following food sources
Meat and fish, and is manufactured by an adult body
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Threonine Amino Acid
Threonine is an essential amino acid, and cannot be manufactured by the body and is found in high concentrations in the heart, skeletal muscles and central nervous system.
Importance of Threonine
It is needed to help maintain the proper protein balance in the body, as well as assist in the formation of collagen and elastin in the skin. It is further involved in liver functioning (including fighting fatty liver), lipotropic functions when combined with aspartic acid and methionine as well as assisting the immune system by helping the production of antibodies and promotes thymus growth and activity. Other nutrients are also better absorbed when threonine is present, and it has also been used as part treatment of mental health.
Deficiency of Threonine
It is a precursor of isoleucine and imbalance may result if the synthesis rate from asparate is incorrect. In humans, deficiency may result in irritability and a generally difficult personality.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Individuals taking supplements normally take a dosage ranging between 103 milligrams and 500 milligrams daily
Threonine can be found in the following food sources
Meats, dairy and eggs, wheat germ, nuts, beans and some vegetables
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Tryptophan Amino Acid
Tryptophan is an essential amino acid and is needed to maintain optimum health.
Importance of Tryptophan
Tryptophan is needed for the production of niacin (vitamin B3). It is used by the human body to produce serotonin, a neurotransmitter that is important for normal nerve and brain function. Serotonin is important in sleep, stabilizing emotional moods, pain control, inflammation, intestinal peristalsis, etc. It is further important in controlling hyperactivity in children, assists in alleviating stress, helps with weight loss and reducing appetite. It has also been found that people suffering from migraine headaches have abnormal levels of tryptophan, and in this supplementation may be helpful.
Deficiency of Tryptophan
A shortage of tryptophan, combined with a shortage of magnesium may be a contributing factor to heart artery spasms.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
In certain studies supplementation of 300 mg - 600 mg per day was experimented with to help with sleep disturbances, migraines, weight loss, appetite control, anxiety and depression, but a supplementation of 100 mg at night-time proved beneficial to promote better sleep.
Risks of Toxicity and symptoms of high intake
Supplementation with high dosage of this amino acid could lead to gastrointestinal upsets, headaches, sleepiness and anxiety.
Tryptophan can be found in the following food sources
Cottage cheese, meat, soy protein and peanuts.
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Tyrosine Amino Acid
Tyrosine is abundant in insulin as well as the enzyme papain and can be synthesized from the amino acid phenylalanine in the body. It is a precursor of the neurotransmitters epinephrine, norepinephrine and dopamine, all of them extremely important in the brain and transmits nerve impulses and prevents depression. Dopamine is also vital to mental function and seems to play a role in sex drive
Importance of Tyrosine
The role of this amino acid in brain functions is clear with its link to dopamine as well as norepinephrine, but it is also helpful in suppressing the appetite and reducing body fat, production of skin and hair pigment, the proper functioning of the thyroid as well as the pituitary and adrenal gland. It is used for stress reduction and may be beneficial in narcolepsy, fatigue, anxiety, depression, allergies, headaches as well as drug withdrawal. In a study, using soldiers, tyrosine proved effective in alleviating stress and keeping them more alert.
Deficiency of Tyrosine
Tyrosine, a parent amino acid for skin, hair, and eye pigments and is involved in syndromes, known generally as oculocutaneous albinism, that are characterized by the failure to form melanin pigments, resulting in partial or complete albinism. It is also the precursor amino acid for the thyroid gland hormone thyroxin, and a defect in this may result in hypothyroidism - an enlargement of the thyroid gland (goiter), severe growth failure, and retardation of central nervous system development. A deficiency may also have symptoms of low blood pressure, low body temperature (including cold hands and feet) and "restless leg syndrome".
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Dosage levels are not confirmed but some experiments have been performed with people taking up to 5 - 7 grams per day, with no confirmed toxic levels, but people taking MAO inhibitors, who suffer from high blood pressure and have problems with skin cancer should not take supplementation of L-tyrosine, and should aim to limit their intake of food sources high in this nutrient.
Tyrosine can be found in the following food sources
Meat, dairy, eggs as well as almonds, avocados and bananas.
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Valine Amino Acid
Valine is an amino acid obtained by hydrolysis of proteins and was first isolated by the German chemist Emil Fischer in 1901 from casein and is not only an essential amino acid but is also a branched-chain amino acid (the others are isoleucine and leucine) found in high concentration in the muscles.
Importance of Valine
It has a stimulating effect and is needed for muscle metabolism, repair and growth of tissue and maintaining the nitrogen balance in the body. As it is a branched-chain amino acid, it can be used as an energy source in the muscles, and in doing so preserves the use of glucose.
Many amino acids become deficient with drug addiction, and here it also plays an important role and there are indications that it may also be beneficial in treating or reversing hepatic encephalopathy, or alcohol related brain damage, as well as degenerative neurological conditions. Valine is often used by bodybuilders, (in conjunction with leucine and isoleucine), to promote muscle growth, tissue repair and energizer, although little scientific evidence supports these claims. Studies have however shown that these three substances might be useful in restoring muscle mass in people with liver disease, injuries, or who have undergone surgery.
Deficiency of Valine
Maple syrup urine disease (MSUD) is caused by the inability to metabolise leucine, isoleucine, and valine. The disease is so named because urine from affected people smells like maple syrup. A deficiency may affect the myelin covering of the nerves.
Recommended Dietary Allowance
The RDA is based more on Amino Acid supplements in either capsule, tablet, powder or liquid form and does not necessary have any adverse effects when taken in by natural foods or when and individuals’ immune system is compromised, but be aware that this RDA is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the risks of toxicity levels must be kept in mind.
Risks of Toxicity and symptoms of high intake
Very high levels of valine can cause symptoms such as a crawling sensation on the skin, as well as hallucinations. Individuals with kidney or liver disease should be careful in consuming high intakes of amino acids without consulting their doctor.
Valine can be found in the following food sources
Dairy, meat, grain, mushrooms, soy and peanuts
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