Amino acids are the basic chemical building blocks of life. The body uses twenty-nine dietary amino acids to synthesize over 50,000 unique proteins and 20,000 enzymes necessary for optimal health. As long as the body has a reliable source of dietary essential amino acids it can adequately meet most of its needs for new protein synthesis. Conversely, if depleted or cut off from dietary sources of amino acids, protein synthesis is affected and serious health problems arise.
Alanine is a non-essential amino acid that can be manufactured by the body from other sources as needed. Alanine is one of the simplest of the amino acids and is involved in the energy-producing breakdown of glucose. In conditions of sudden anaerobic energy need, when muscle proteins are broken down for energy, alanine acts as a carrier molecule to take the nitrogen-containing amino group to the liver to be changed to the less toxic urea, thus preventing buildup of toxic products in the muscle cells when extra energy is needed.
Because the body easily constructs alanine from other sources, no deficiency state is known. Alanine is found in a wide variety of foods, but is particularly concentrated in meats.
Arginine is an amino acid which becomes an essential amino acid when the body is under stress or is in an injured state. Depressed growth results from lack of dietary arginine. Arginine is indispensable for certain adult mammals. When mammals who ordinarily consume an arginine-rich diet are deprived of arginine, death ensues. Arginine deficiency syndrome is observed in human babies born with a phosphate synthetase deficiency. Normal growth and development in these infants are achieved by adding arginine to their diet. Arginine deficiency leads to carbamyl phosphate overproduction in the mitochondria due to inadequate ornithine supply. Arginine-deficient diets in males causes decreased sperm counts. Free and bound arginine are found in abundance in human male sperm and arginine has been found to stimulate sperm motility.
There are two sources of arginine; arginine in the food chain and free-form arginine from supplements. Food-source arginine is found in abundance in turkey, chicken, and other meats. Non-food-source arginine is called L-arginine and is created through a fermentation process which separates arginine from all other proteins. In the presence of food and other amino acids, L-arginine will act like food-source arginine but when L-arginine is separated from its nutrient boundaries by the removal of all other amino acids, then L-arginine undertakes a different role, becoming capable of crossing the blood-brain barrier and stimulating growth hormone release secreted by the anterior pituitary.
Growth hormone serum levels peak during adolescence and begin to drop after age 23. Aging reduces natural growth hormone production, which results in added body fat, reduced muscle tissue, slowed healing, lack of elasticity in the skin, and reduced immune function.
Human pituitary growth hormone secretion is evidenced in human males, females, and children following intravenous administration of 30 grams of arginine (in 30 minutes) in adults and 0.5 grams/kilogram of bodyweight in children. Female response is somewhat higher than male response. Oral administration of L-arginine also results in the release of Human Growth Hormone. Oral ingestion of another amino acid, Ornithine, results in growth hormone release, but since arginine turns into ornithine, and ornithine does not replace arginine for growth, arginine is the superior growth hormone releasing agent.
Additionally, arginine has very low toxicity. Doses of 0.5 grams per kilogram up to 30 grams total given within 20 to 30 minutes has caused no untoward reactions and is considered safe. Patients diagnosed with renal or hepatic insufficiency and those with insulin-dependent diabetes should avoid large doses of arginine, or be medically monitored. Normal persons can tolerate 30 to 60 grams per day arginine. While food-source arginine is necessary for growth in children, free-form L-arginine is not recommended for anyone under the age of 23.
The body’s demand for dietary arginine is increased by physical trauma (of any type). Dietary supplementation of arginine:
- Increases collagen; the protein providing the main support for bone, cartilage, tendons, connective tissue, and skin.
- Increases wound breaking strength.
- Improves the rate of wound healing.
- Inhibits cellular replication of tumors.
- Increases sperm count and motility by over 100%.
- Detoxifies ammonia (The urea cycle is the metabolic detoxification process utilized by the body to eliminate toxic ammonia in which ammonia is turned into urea and excreted in the urine).
- Minimizes thymic involution that occurs with injury.
- Decreases nitrogen losses after trauma.
The demand for arginine in humans and animals occurs in response to:
- Physical trauma,
- Dorsal skin wounds,
- Physical pain registered by the skin,
- Blood transfusions (pinprick reactions as well as foreign substance reaction),
- Tumor burden and malignancies,
- Dental procedures (pinprick reaction, pain, and blood loss),
- Muscle and bone growth spurts.
Tumor suppression is evidenced in the presence of L-arginine. In the Barbul study, tumors recurred in 100% of the control animals. But in the arginine-supplemented group, only about 60% of the tumors recurred and the animals with tumors survived longer
Supplementation of arginine in the diet inhibits development and increase in size of cancerous tumors, both chemically induced and naturally occurring.
Insulin can block growth hormone release, so high serum insulin levels are counterproductive to GH release. Insulin itself is capable of stimulating muscle growth, but it also strongly stimulates fat storage. Muscle growth stimulation from insulin is minuscule compared to muscle growth stimulated by growth hormone.
Adults who choose to take L-arginine supplements for growth hormone release should observe the following guidelines. The product:
- Should not be in capsule form – you cannot fit enough L-arginine in capsules to elicit a GH response.
- Should not contain Lysine. L-arginine and Lysine should not be taken together as Lysine is a direct antagonist of arginine. L-arginine taken near food can interfere with Lysine metabolization thus causing potential reactivation of an already existing herpes virus.
- Should not contain competing proteins or amino acids.
- Should not contain insulin stimulating (high glycemic) ingredients.
- Should contain the correct synergists.
- Should include explicit directions in regard to timing and contraindications (ie diabetics)
In Italy, Arginine Pyroglutamate is used to treat senility, mental retardation, and alcoholism. Arginine pyroglutamate is simply an arginine molecule combined with a pyroglutamate molecule. Arginine alone does not produce cognitive enhancing effects. It is likely that pyroglutamate is the active ingredient of arginine pyroglutamate.
No serious adverse effects from the use of pyroglutamate, or from the use of arginine pyroglutamate, have been reported. Arginine and pyroglutamate are amino acids found commonly in natural foods and consumed by most people on a daily basis.
Asparaginine is a non-essential amino acid that was first isolated from sprouting soybeans. Structurally similar to aspartic acid, with an additional amino group on the main carbon skeleton, Asparaginine aids in the metabolic functioning of brain and nervous system cells. When the extra amino group is removed by the brain, the resulting aspartic acid acts as an excitatory transmitter. Aspartic acid has been used to help with fatigue and depression, and may be a mild immune stimulant as well. In the body, removal of asparaginines extra amino group allows it to be used interchangeably with aspartic acid in basic protein building. It is easily supplied in normal diets and no toxic effects are known.
Aspartic acid a non-essential amino acid that the body can make from other sources in sufficient amounts to meet its needs. It is a critical part of the enzyme in the liver that transfers nitrogen-containing amino groups, either in building new proteins and amino acids, or in breaking down proteins and amino acids for energy and detoxifying the nitrogen in the form of urea.
Recent studies have shown aspartate and arginine supplements either alone or in combination may help relieve chronic fatigue. Both amino acids are also helpful in treating decreased fertility in men caused by decreased sperm count or mobility. Aspartic acid and potassium aspartate were also helpful in treating heart attacks and preventing irregular rhythms.
Its ability to increase endurance is thought to be a result of its role in clearing ammonia from the system. In one study, 85% of 145 patients with chronic fatigue who were given the potassium and magnesium salts of aspartic acid, felt significantly more energetic. Athletes also use it to promote stamina and endurance. It helps form the ribonucleotides that assist in the production of RNA and DNA, and assists in energy production from carbohydrate metabolism.
Aspartic acid is one of two major excitatory amino acids within the brain (The other is glutamic acid). At small doses these amino acids stimulate nerve cells to higher levels of activity. At higher doses they may overexcite these nerve cells, causing cell damage or death. This is thought to happen in strokes, when large amounts of excitatory neurotransmitters are released by the damage and may contribute to further damage. Some research has shown that aspartic acid might be useful in opiate withdrawal. It was found more useful in this context than some major tranquilizing drugs.
Depleted levels of aspartic acid may occur temporarily within certain tissues under stress, but, because the body is able to make its own aspartic acid to replace any depletion, deficiency states do not occur. Aspartic acid is abundant in plants, especially in sprouting seeds. In protein, it exists mainly in the form of its amide, asparagine. The popular sweetener Aspartame is a combination of aspartic acid and phenylalanine. Aspartic acid is considered nontoxic.
Carnitine is a dipeptide – an amino acid made from two other aminos, methionine and lysine. It can be synthesized in the liver if sufficient amounts of lysine, B1, B6 and iron are available. Muscle and organ meat, fish and milk products are the best sources of carnitine in the diet. Vegetarians are more likely to be deficient in carnitine because they don’t eat meat and their diets are often low in lysine.
Carnitine has been shown to have a major role in the metabolism of fat and in the reduction of triglycerides by increasing fat utilization. It transfers fatty acids across the membranes of the mitochondria where they can be utilized as sources of energy. It also increases the rate at which the liver uses fats. By preventing fatty build-up, this amino acid aids in weight loss and decreases the risk of heart disease.
Carnitine has been shown to be deficient in hearts of patients who have died of acute myocardial infections. Supplements have recently been found to improve exercise tolerance in people with angina, possibly by increasing the ability to utilize fatty acids for energy.
Carnitine was also found to block atrial fibrillation after initial atropine administration about as well as quinidine, without many of quinidine’s side effects. It may be deficient, and supplementation may help in mitral valve prolapse and immune system depression. Muscular dystrophy, and myotonic dystrophy have been shown to lead to carnitine loss in the urine, and therefore higher requirements for it.
Carnitine is stored primarily in the skeletal muscles and heart, where it is needed to transform fatty acids into energy for muscular activity. It is also concentrated in sperm and the brain. Many athletes have noted increased endurance and muscle building with carnitine supplementation. The Physicians Desk Reference has recommended l-carnitine in the treatment of ischemic heart disease and Type IV hyperlipidema. Carnitine has been shown to be beneficial for heart problems such as angina, ischemia or arrhythmia, and poor endurance, muscle weakness or obesity.
Deficiencies may increase symptoms of fatigue, angina, muscle weakness or confusion. A low level of Vitamin c will also result in apparent Carnitine deficiency. It is contraindicated for people with liver or kidney disease or diabetes It has proven helpful in improving lipid metabolism and reducing elevated total lipids, cholesterol and triglycerides in people with cardiac problems and diabetes, but should only be taken with medical supervision in these conditions.
Citruline is synthesized in the body from ornithine by the addition of carbon dioxide and ammonia, and is a precursor of arginine. It is found primarily in the liver and is a major component of the urea cycle. Therapeutically it is used for the detoxification of ammonia, a byproduct of protein breakdown, and in the treatment of fatigue. It is also thought to stimulate the immune system. Onions and garlic contain an abundance of citruline.
Cysteine is a sulphur-bearing amino acid and a precursor to Glutathione, one of the body’s most effective antioxidants and free radical destroyers. Free radicals are toxic waste products of faulty metabolism, radiation and environmental pollutants which oxidize and damage body cells. Glutathione also protects the liver and brain from the damaging effects of cigarettes and alcohol, protects red blood cells from oxidative damage and aids in amino acid transport. Glutathione specifically helps neutralize the aldehydes produced by the liver as a by-product in the metabolism of fats, alcohol, air pollutants and some drugs. It works most effectively when taken in conjunction with vitamin E and selenium.
Through this antioxidant enzyme process, cysteine may contribute to a longer life span, as deterioative aging is thought to be mainly due to oxidation and free radical damage. Cysteine has been shown to be effective in preventing and the treatment of atherosclerosis, heart attacks, cancer, osteoarthritis and rheumatoid arthritis. It has immune enhancing properties, promotes fat burning and muscle growth and also tissue healing after surgery or burns.
Hair is 8% cysteine by weight, and cysteine supplements have been shown to be helpful in reducing hair loss and stimulating hair growth. It is important to take vitamin C at the same time and in three times the amount of cysteine, in order to prevent cysteine from being converted to cystine which may form damaging stones in the kidney or bladder.
Cysteine can be found in sulphur containing foods such as egg yolks, red peppers, garlic, onions, broccoli and brussels sprouts. It can be helpful in hypoglycemia as it can block the harmful effects of excess insulin. Use of Cysteine is contraindicated for diabetics.
Cystine is a stable form of the amino acid cysteine. The body is capable of converting one to the other as required and in metabolic terms they can be thought of as the same. Both cystine and cysteine are rich in sulphur and can be readily synthesized by the body. Cystine is found abundantly in hair keratin, insulin and certain digestive enzymes.
As a detoxification agent Cystine has been shown to protect the body against damage induced by alcohol and cigarette smoking. One study showed its effectiveness in preventing the side effects of drinking, such as hangover, and that it prevented liver and brain damage as well.
Cystine or cysteine is needed by the body for proper utilization of vitamin B6. The metabolic steps in the formation of these two amino acids is from methionine to cystathionine to cysteine to cystine. In chronic diseases it appears that the formation of cysteine from methionine is prevented.
One element in correction of the biochemistry of the chronic disease could be the restoration of adequate levels of cysteine or cystine. Cysteine is more soluble than cystine and contributes sulphur more readily and thus achieves better results in some patients.
No single nutrient should be seen as curative for any condition. By reducing the body’s absorption of copper, cystine protects against copper toxicity, which has been linked to behavioral problems. It is also found helpful in the healing of burns and wounds, and is used to break down mucus deposits in illnesses such as bronchitis and cystic fibrosis. Cysteine also assists in the supply of insulin to the pancreas, which is needed for the assimilation of sugars and starches. However, supplements of cysteine and cystine are readily utilized carbon sources that may actually enhance Candida growth in its more pathogenic yeast form.
GABA (gamma aminobutyric acid), is an important amino acid which functions as the most prevalent inhibitory neurotransmitter in the central nervous system. Supplemental GABA can be useful in producing a state of relaxation. GABA works in partnership with a derivative of Vitamin B-6, pyridoxine, to cross from the axons to the dendrites through the synaptic cleft, in response to an electrical signal in the neuron and inhibits message transmission. This helps control the nerve cells from firing too fast, which would overload the system.
The action of GABA decreases epileptic seizures and muscle spasms by inhibiting electrical signals in this manner. Studies have shown that the site of action in the brain of benzodiazepams, including Valium, is directly coupled to the brain receptor for GABA. GABA itself can be taken instead of a tranquilizer to calm the body without the fear of addiction. Taken with the B-vitamins niacinamide and inositol, it prevents anxiety messages from reaching the motor centers of the brain by filling its receptor site.
Glutathione is a tri-peptide composed of three amino acids: Cysteine, Glutamic Acid and Glycine. Glutathione and the enzymes it forms, such as GTH peroxidase, are essential to all life and are found in tissues of virtually all plants and animals. GTH is present in all human cells, with the highest levels found in the liver, the lenses of the eyes, pancreas, spleen and kidneys.
Glutathione acts as a powerful antioxidant, a key protector against all types of pollution and is effective in preventing aging. Glutathione also protects against cellular peroxidation caused by exposure to pesticides, plastics, benzene and carbon tetrachloride, as well as heavy metals, cigarette smoke, smog, drugs, solvents, dyes, phenols and nitrates.
Glutathione works to inhibit the formation of free radicals, dangerous agents that suppress the immune system and promote the formation of mutagens and carcinogens. Free radicals also speed up the aging process, and it is due to this antioxidant activity that Glutathione is considered useful in the prevention and treatment of a wide range of degenerative diseases.
Studies at the Louisville School of Medicine have clearly shown that Glutathione possesses unique ability to slow the aging process. While Glutathione aids in the protection of all cells and membranes, a study at Harvard Medical School found that glutathione is especially able to enhance immune system cells, protecting against damage from radiation and helping to reduce the side effects of chemotherapy and x-rays and alcohol. As a detoxifier of metals and drugs, glutathione also aids in the treatment of blood and liver disorders.
Glutamine is an amino acid widely used to maintain good brain functioning. Glutamine is a derivative of glutamic acid which is synthesized from the amino acids arginine, ornithine and proline. Glutamine improves mental alertness, clarity of thinking and mood. It is found abundantly in animal proteins and needed in high concentrations in serum and cerebro-spinal fluid. When glutamic acid combines with ammonia, a waste product of metabolic activity, is converted into glutamine.
Glutamic acid is also a precursor of GABA, an important neurotransmitter in the central nervous system. Glutamic acid helps transport potassium into the spinal fluid and is itself an excitatory neurotransmitter. Glutamic acid has been used to treat mental retardation, epilepsy, Parkinson’s disease, muscular dystrophy and alcoholism.
Because glutamic acid cannot cross the blood brain barrier, where most of the metabolism takes place, glutamine, which can cross this barrier, works better in supplement form. Glutamine can also be used by cells like glucose for metabolic energy. It helps to raise blood sugar and is therefore valuable in the treatment of hypoglycemia.
Research has also shown that supplementation of glutamine reduces the craving for alcohol and is now commonly used in alcoholism clinics. It also seems to reduce the craving for sugar and carbohydrates. Other noted areas of usefulness are treatment of depression, peptic ulcers, schizophrenia and senility, and behavioral problems and autism in children.
Glycine is an amino acid that is a major part of the pool of amino acids which aid in the synthesis of non essential amino acids in the body. Glycine can be easily formed in the liver or kidneys from Choline and the amino acids Threonine and Serine. Likewise, Glycine can be readily converted back into Serine as needed. Glycine is also one of the few amino acids that can spare glucose for energy by improving glycogen storage. Glycine is also readily converted into creatine, which is utilized to make RNA and DNA.
Glycine is required by the body for the mainainence of the central nervous system, and in men glycine plays an essential role in maintaining healthy prostate functions. Glycine also plays an important function in the immune system were it is used in the synthesis of other non-essential amino acids.
Studies have shown that glycine can be beneficial in cases of chronic spasticity, including multiple sclerosis, and its inhibitory action can help to prevent epileptic seizures. Glycine has also been used in treating manic psychological states and has a calming effect on the brain. Glycine can reduce gastric acidity, and in higher doses, can stimulate growth hormone release and contribute to wound healing Glycine comprises up to a third of the collagen in the human body and is required for the synthesis of the porphyrin core of hemoglobin, the oxygen-carrying molecule in the blood. Glycine is also a constituent of a vital bile acid, and together with cysteine and glutamic acid, makes up glutathione, a major liver detoxifier and free radical fighter.
Histidine is intricately involved in a large number of critical metabolic processes, ranging from the production of red and white blood cells to regulating antibody activity. Histidine also helps to maintain the myelin sheaths which surround and insulate nerves. In particular, Histidine has been found beneficial for the auditory nerves, and a deficiency of this vital amino acid has been noted in cases of nerve deafness.
Histidine is required for the production of histamine, and is often used in the treatment of anemia, allergies, rheumatoid arthritis and other inflammatory reactions. Histidine also possesses vasodilating and hypotensive actions, and has an vital role in sexual responses. Research shows that the release of histamine from the mast cells is necessary for the physical action of orgasm. Women who are unable to achieve orgasm may be low in histamine and can possibly benefit from histidine supplementation. Premature ejaculation is also attributed to excess histamine and may be regulated by using methionine and calcium.
Studies show that histidine boosts the activity of suppressor T cells. One researcher reporting the finding of abnormally low levels of Histidine in the blood of patients with rheumatoid arthritis. Histidine is also used as a chelating agent in some cases of arthritis and to treat tissue overload from copper, iron or other heavy metals, to remove them from the body
Histidine also acts as an inhibitory neurotransmitter, boosting the activity of soothing alpha waves in the brain and suporting resistant to the effects of anxiety and stress. In cases of histidine deficiency, there is an unbalancing effect on alpha rhythms, leading to greater beta wave production. Beta waves are responsible for brain activity leading to anger and tension.
Histidine is naturally found in most animal and vegetable proteins, and is especially high in pork, poultry, cheese and wheat germ. Supplements of histidine should not be larger than 1.5 grams per day, except under a doctors supervision.
Isoleucine is a essential branched chain amino acid found abundently in most foods. Isoleucine is found in especially high amounts in meats, fish, cheese, most seeds and nuts, eggs, chickens and lentils.
In the human body Isoleucine is concentrated in the muscle tissues. Isoleucine is necessary for hemoglobin formation and in stabilizing and regulating blood sugar and energy levels. A deficiency of isoleucine can produce symptoms similar to those of hypoglycemia. It has been identified as one of a group of amino acids deficient in amino acid profiles run on mentally and physically ill patients. Isoleucine is frequently deficient in the elderly, and may contribute to muscle wasting, twitching and tremors.
The branched chain amino acids (BCAAs) are Isoleucine, Leucine and Valine. BCAAs are popular with body builders looking to restore muscle mass traumatized from excessive overtraining. BCAAs are also used to treat injuries and physical stress conditions , such as surgery and liver disease. The ability of these amino acids to help in abnormal conditions does not imply that they will help in healthy individuals, and no studies indicate that extra intake will help in muscle building.
Since the body cannot make this amino acid from other sources, maintaining sufficient amounts in the diet IS important. Jeffery Bland, author of Medical Applications of Clinical Nutrition, gives the range of isoleucine requirement in normal adults as being between 250 and 700 milligrams daily. The isoleucine content of animal protein is 42 milligrams per gram of protein.
Leucine is an essential amino acids which cannot be synthesized by the body but must always be acquired from dietary sources. Leucine is available in good concentrations in meat and dairy products, and to a lesser degree in wheat germ, brown rice, soybeans, almonds, cashews and brazil nuts, chickpeas, lentils and corn. Leucine stimulates protein synthesis in muscles, and is essential for growth. Leucine also promotes the healing of bones, skin and muscle tissue.
Leucine, and the other branched-chain amino acids (BCAAs), Isoleucine and Valine, are frequently deficient in the elderly, and increased body requirements can occur after trauma or surgery. These branched-chain amino acids may prevent muscle wasting in these conditions, but no studies have been done to determine if extra intake will help in muscle building in healthy individuals. Because leucine cannot be made by the body from other sources, it IS important to maintain adequate amounts in the diet.
Leucine, in conjunction with two other amino acids, isoleucine and valine, appear to be quite helpful in treating and in some cases even reversing hepatic encephalopathy, a form of liver damage in alcoholics. They also help curb muscle wasting in this disease and through their actions on brain neurotransmitters, help prevent some adverse neurological effects of chronic liver disease.
A recent study shows that leucine, isoleucine and valine may be helpful in ALS, known as Lou Gehrig disease. This is a potentially fatal disease for which no other effective treatment has been found. This pilot study involved nine ALS patients, of whom eight benefitted from supplementation with these amino acids, top the extent that over the one year period of the study, they retained their muscle strength and their ability to walk. Five of the nine control subjects, who received placebos, lost their ability to walk over this period.
A study reported in the British Journal of Nutrition found that a dietary excess of leucine may be a precipitating factor in causing pellagra. This effect was only apparent when the diet also provided less than adequate amounts of nicotinamide. The right handed, or D form of leucine, has been shown to have a similar effect to that of d-phenylalanine in retarding the breakdown of the natural pain killers of the body, the endorphins and enkephalins.
Lysine is one of the essential amino acids that cannot be manufactured by the human body, but must be acquired from food sources. The best food sources for Lysine are lean meats, fish, potatoes and milk.
In the early 1980’s lysine became well known for its ability to fight the Herpes Simplex-1 virus, mouth blisters and cold sores. Since then it has been shown to have broader immune enhancing effects. Some studies have shown it effective in relieving genital herpes. High doses of Lysine stop viral growth and reproduction, and aids in the production of antibodies, hormones and enzymes.
In children lysine is needed for proper growth and bone development. Its aids calcium absorption and maintains nitrogen balance in adults. It is also instrumental in the formation of collagen, which is the basic matrix of the connective tissues, skin, cartilage and bone. According to Linus Pauling, lysine may also help reduce angina pectoris, chest pain caused by insufficient oxygen in the heart muscle. Pauling recommends 5 grams divided throughout the day for this condition. Lysine aids in collagen formation, in the repair of tissue, and helps to build muscle protein, all of which are important for recovery from surgery and injuries. It also lowers high serum triglycerides.
Lysine supplements stimulate the liver to produce higher levels of cholesterol and triglycerides. Lysine deficiencies can result in lowered immune function, loss of energy, bloodshot eyes, irritability, hair loss, retarded growth, and reproductive disorders, increases urinary excretion of calcium, and increases the risk of kidney stones in susceptible people. Lysine has no known toxicity.
Methionine is an essential amino acid that is not synthesized by the body and must be obtained from food. It is one of the sulphur containing amino acids and is important in many body functions. Through its supply of sulphur, it improves the tone and pliability of the skin, conditions the hair and strengthens nails. The mineral sulphur also protects the cells from airborne pollutants, such as smog, slows down the aging process in the cells, and is involved with the production of protein.
Methionine is essential for the absorption and transportation and bioavailability of selenium and zinc in the body. It also acts as a lipotropic agent to prevent excess fat buildup in the liver, and is an excellent chelator of heavy metals, such as lead, cadmium and mercury, binding them and aiding in their excretion from the body.
It can help fatigue and may be useful in some cases of allergy because it reduces histamine release. It has also been used in the treatment of rheumatic fever and toxemia resulting from pregnancy. Recent studies show methionine deficiencies may be associated with the development of age related cataracts, and supplements may delay their development. In Parkinson’s disease patients taking L-Dopa, it was found that additional supplements with L-Methionine may further decrease the tremors and rigidity that limit normal activities.
The best food sources are beef, chicken, fish, pork, soybeans, eggs, cottage cheese, liver, sardines, yogurt, pumpkin seeds, sesame seeds and lentils. The range of human need for methionine is estimated at between 800 and 3,000 milligrams per day. This represents a 3.7 fold variation, based on a sample of 29 individuals.
Ornithine is made from the amino acid arginine and in turn is a precursor to form glutamic acid, citruline, and proline. Ornithine’s chief therapeutic value lies in its involvement in the urea cycle and its ability to enhance liver function, protect the liver and detoxify harmful substances. It has been used in the treatment of hepatic coma states. It also helps release a growth hormone that metabolizes excess body fat when combined with arginine. This growth hormone is also an immune stimulant.
In animal studies arginine and ornithine have improved immune responses to bacteria, viruses and tumor cells. One study on mice showed both of these amino acids were able to block formation of tumors in mice inoculated with a cancer causing virus. A one percent arginine or ornithine supplement to their food increased the animals thymus weights and lymphocytes in both the inoculated mice and the non inoculated control group, and markedly extended the life span in the animals receiving the virus.
Ornithine has been shown to aid in wound healing and support liver regeneration. It is found in milk products and meat, especially chicken. It may cause insomnia, and is contraindicated for schizophrenics. Growth hormone releasers should not be used by anyone who has not grown to their full height unless advised by their physicians. Excess growth hormone will cause the skin to become coarser and thicker, this is reversed when excess GH is withdrawn. Very excessive growth hormone over an extended period of time can cause irreversible enlargement of the joints and lowering of voice pitch due to larynx growth, and may cause a pituitary form of diabetes.
Phenylalanine is one of the amino acids which the body cannot manufacture itself, but must acquire from food. It is abundant in meats and cheese. Phenylalanine is a precursor of tyrosine, and together they lead to the formation of thyroxine or thyroid hormone, and of epinephrine and norepinephrine which is converted into a neurotransmitter, a brain chemical which transmits nerve impulses. This neurotransmitter is used by the brain to manufacture norepinephrine which promotes mental alertness, memory, elevates mood, and suppresses the appetite very effectively.
In one study, 100-500 milligrams of phenylalanine taken every day for two weeks completely eliminated patients depression. These people where depressed from a variety of causes, including drug abuse and schizophrenia and some from no apparent cause, and the amino acid seemed to work especially well for them all.
Along with another amino acid, tryptophan, phenylalanine governs the release of an intestinal hormone called cholecystokinin, known as CCK. This hormone signals the brain to feel satisfied after eating. People given CCK stop eating and feel full sooner. Various studies have shown Phenylalanine’s ability to decrease chronic back and dental pain and the pain associated with migraines and menstruation in a non-toxic and non-addictive manner.
Phenylalanine comes in two forms which are mirror images of each other: L-phenylalanine which has a nutritional value, and D-phenylalanine which has painkilling and depression alleviating properties which are attributed to its ability to block the breakdown of enkephalins, the brains natural pain killers. A third form, DL-phenylalanine, is a 50/50 mixture of these two forms. Phenylalanine activity is enhanced by additional Vitamin B 6, especially in studies on depression.
Phenylalanine deficiency can cause bloodshot eyes, cataracts and behavioral changes. Nutritional researchers recommend keeping intake of supplemental forms of phenylalanine to no more than 2.4 grams per day. Overuse of phenylalanine supplements can cause anxiety, headaches and hypertension, and are contraindicated for pregnant woman, those who suffer from anxiety attacks, high blood pressure, PKU, pigmented melanoma, or anyone taking an anti-depressant containing MAO inhibitors.
Proline is synthesized by the body from the amino acids glutamine or ornithine. The best food sources for Proline are dairy products and eggs, and in lesser amounts meats and wheat germ. It is one of the main components of collagen, the connective tissue structure that binds and supports all other tissues. It is most effective in this regard when combined with vitamin C supplementation.
Proline improves skin texture and studies have shown that collagen is neither properly formed or maintained if Vitamin C is lacking, so proline is most effective when adequate Vitamin C is supplied at the same time.
Pyroglutamate is an amino acid naturally found in vegetables, fruits, dairy products, and meat. It is also normally present in large amounts in the human brain, cerebrospinal fluid, and blood. After oral administration, pyroglutamate passes into the brain through the blood-brain barriers and helps stimulate cognitive functions. Pyroglutamate improves memory and learning in rats, and has anti-anxiety effects in rats.
Pyroglutamate has also been shown to be effective in alcohol-induced memory deficits in humans2, and more recently, in people affected with multi-infarct dementia3. In these patients, the administration of pyroglutamate brought about a significant increase of attention and an improvement on psychological tests investigating short-term retrieval, long-term retrieval, and long-term storage of memory. A statistically significant improvement was observed also in the consolidation of memory.
In human subjects, pyroglutamate was compared with a placebo in a randomized double-blind trial for assessing its efficacy in treating memory deficits in 40 aged subjects. Twenty subjects were treated with pyroglutamate and 20 with a placebo over a period of 60 days. Memory functions were evaluated at baseline and after 60 days of treatment by means of a battery made up of six memory tasks. The results show that pyroglutamate is effective in improving verbal memory functions in subjects affected by age-related memory decline.
In Italy, arginine pyroglutamate is used to treat senility, mental retardation, and alcoholism. Arginine pyroglutamate is simply an arginine molecule combined with a pyroglutamate molecule. Arginine alone does not produce cognitive enhancing effects. It is likely that pyroglutamate is the active ingredient of arginine pyroglutamate.
No serious adverse effects from the use of pyroglutamate, or from the use of arginine pyroglutamate, have been reported. Arginine and pyroglutamate are amino acids found commonly in natural foods and consumed by most people on a daily basis.
Serine is synthesized by the body from the amino acids glycine or threonine. Its production requires adequate amounts of B-7 (niacin), B-6, and folic acid. It is needed for the metabolism of fats and fatty acids, muscle growth and a healthy immune system. It aides in the production of immunoglobulins and antibodies. It is a constituent of brain proteins and nerve coverings. It is 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.
Serine is abundant in meats and dairy products, wheat gluten, peanuts and soy products, all of which are common allergens. There is some concern that elevated serine levels can cause immune suppression and psychological symptoms as in cerebral allergies.
Taurine is one of the most abundant amino acids in the body. It is found in the central nervous system, skeletal muscle and is very concentrated in the brain and heart. It is synthesized from the amino acids methionine and cysteine, in conjunction with vitamin B6. Animal protein is a good source of taurine, as it is not found in vegetable protein. Vegetarians with an unbalanced protein intake, and therefore deficient in methionine or cysteine may have difficulty manufacturing taurine. Dietary intake is thought to be more important in women as the female hormone estradiol depresses the formation of taurine in the liver.
Taurine seems to inhibit and modulate neurotransmitters in the brain. There have been reports on the benefits of taurine supplementation for epileptics. It has also been found to control motor tics, such as uncontrollable facial twitches. Taurines’ effectiveness in epilepsy has been limited by its poor diffusion across the blood-brain barrier.
In Japan, taurine therapy is used in the treatment of ischemic heart disease. Low taurine and magnesium levels have been found in patients after heart attacks . Like magnesium, taurine affects cell membrane electrical excitability by normalizing potassium flow in and out of heart muscle cells. Supplements decrease the tendency to develop potentially lethal abnormal heart arrythmias after heart attacks.. People with congestive heart failure have also responded to supplementation with improved cardiac and respiratory function.
Another role played by taurine is maintaining the correct composition of bile, and in maintaining the solubility of cholesterol. It has been found to have an effect on blood sugar levels similar to insulin. Taurine helps to stabilize cell membranes and seems to have some antioxidant and detoxifying activity. It helps the movement of potassium, sodium, calcium and magnesium in and out of cells, which helps generate nerve impulses.
Taurine is necessary for the chemical reactions that produce normal vision, and deficiencies are associated with retinal degeneration. Besides protecting the retina, taurine may help prevent and possibly reverse age-related cataracts. Low levels of taurine and other sulphur containing amino acids are associated with high blood pressure, and taurine supplements have been shown to lower blood pressure in some studies.
Other possible uses for Taurine supplementation include eye disease, cirrhosis, depression and male infertility due to low sperm motility and hypertension. Possible symptoms of toxicity include diarrhea and peptic ulcers. For those considering taurine supplements, taurine is known to have a calming or depressant effect on the central nervous system, and may impair short term memory. Taurine is present in meats and animal products, but not in plant products.
Threonine, an essential amino acid, is not manufactured by the body and must be acquired from food. It is an important constituent in many body proteins and is necessary for the formation of tooth enamel protein, collagen and elastin. It is a precursor to the amino acids glycine and serine. It acts as a lipotropic in controlling fat build-up in the liver.
One researcher considers Threonine, along with B vitamins, magnesium, ascorbic acid, iodine, potassium, tryptophan, lysine, inositol and glutamic acid, as being essential in the treatment and prevention of mental illness. Another states that Threonine “is very useful in indigestion and intestinal malfunctions and prevents excessive liver fat. Nutrients are more readily absorbed when threonine is present.” Preliminary studies in patients with the degenerative neuromuscular disease ALS showed definite symptom improvement with L-threonine supplements. Since there is no other treatment for this disease, it may prove useful in allowing these people a better quality of lifestyle.
There are good levels of threonine in most meats, dairy foods and eggs and moderate levels in wheat germ, many nuts, beans and seeds and some vegetables. Threonine is an immune stimulant-it promotes thymus growth and activity. L-threonine deficiency in rats has been associated with weakened cellular response and antibody formation. In humans, deficiency results in irritability and generally difficult personality, according to one researcher. The range of human requirements is stated to be between 103 milligrams and 500 milligrams daily .
Tryptophan, an essential amino acid, is one of the amino acids which the body cannot manufacture itself, but most acquire from food. It is the least abundant in proteins and also easily destroyed by the liver. Tryptophan is necessary for the production of the B-vitamin niacin, which is essential for your brain to manufacture the key neurotransmitter serotonin. Scientists have linked low serotonin levels with insomnia, anxiety and depression. It helps control hyperactivity, relieves stress, suppresses the appetite and enhances the release of growth hormones.
More than forty studies have shown the effectiveness of Tryptophan for insomnia. It has been shown to enable people to fall asleep more quickly, and to increase sleep time without the hangover effect of regular sleeping pills. Studies have also found it effective for jet lag. In one study at the University of California School of Medicine, fifty one marines were flown across eight time zones. Half received tryptophan and the other half placebos. Those who got the amino acid were able to sleep more and responded better on performance tests and reaction times.
Other studies show tryptophan to have anti-anxiety effects and control aggressive behavior in some individuals. Used in combination with drug therapy, Tryptophan has helped previously unresponsive depressed patients. Another study showed it’s anti-depressant effect to be of longer duration than the popular anti-depressant drug Imipramine.
Some evidence shows that this amino acid may also be effective for people suffering from chronic pain. Sensitivity to pain is partly affected by the serotonin levels in your brain. People taking Tryptophan in addition to their standard pain medications, reported fewer painful, debilitating symptoms than when they used the pain drugs alone. Tryptophan decreases amphetamine craving in animal studies and it may also have a role in alcohol withdrawal. Preliminary studies of combined Vitamin B-6 and tryptophan show that they may reduce the severity of hyperventilation and the panic attacks it may produce.
The best food sources of Tryptophan are pineapple, turkey, chicken, yogurt, bananas and unripened cheese. Combining these foods with some carbohydrates, such as pasta, cereal or bread etc., will enable your brain to absorb the tryptophan more effectively, where it is used to manufacture serotonin.
Although Tryptophan has a long history of safe use, in December 1989 the FDA reported over 600 cases of a flu-like syndrome associated with a blood abnormality in those taking the amino acid. Although the problem was traced to a contaminated batch, Tryptophan is no longer available in supplement form. Because of potential adverse reactions, tryptophan supplements are not recommended in pregnant women, asthmatics or people with auto-immune disorders like Lupus or Scleroderma.
Tyrosine is an amino acid synthesized from phenylalanine in the body. It is a precursor of the important brain neurotransmitters epinephrine, norepinephrine and dopamine, which transmit nerve impulses and are essential to prevent depression. Dopamine is vital to mental function and seems to play a role in sex drive.
Tyrosine is also used by the thyroid gland to produce one of the major hormones, Thyroxin. This hormone regulates growth rate, metabolic rate, skin health and mental health. It is used in the treatment of anxiety, depression, allergies and headaches. Animals subjected to stress in the laboratory have been found to have reduced levels of the brain neurotransmitter norepinephrine. Doses of tyrosine prior to stressing the animals prevents reduction of norepinephrine.
Human trials have been performed with soldiers placed in various forms of stress. Those soldiers receiving Tyrosine were found to perform better on a variety of tests. They were more efficient, alert and had fewer complaints. Clinical studies have shown that tyrosine can be helpful in reducing the irritation, tiredness and depression of PMS sufferers, as well as being an effective antidepressant in some more major forms of depression.
Tyrosine is used with the amino acid Tryptophan, to aid in the treatment of cocaine abuse, with some success. In one study the two amino acids were used in conjunction with the anti-depressant Imipramine to treat chronic cocaine abuse with a reported 75-80% success rate. Most of the people in the study reported that this combination blocked the cocaine high and warded off the severe depression that typically accompanies withdrawal.
Intake of Tyrosine is contraindicated for people taking antidepressants containing monoamine oxidase (MAO) inhibitors, people with high blood pressure or skin cancer. It may trigger migraine headaches. The main sources of tyrosine in the diet are meats, dairy products and eggs.
Valine is one of the amino acids which the body cannot for manufacture itself but must acquire from food sources. Valine is found in abundant quantities in most food. Valine has a stimulant effect. Healthy growth depends on it. A deficiency results in a negative hydrogen balance in the body.
Valine is used by bodybuilders, in conjunction with leucine and isoleucine, for muscle growth, tissue repair and as an energizer. There is little scientific evidence to support these claims, though studies have shown that these three substances might be able to help restore muscle mass in people with liver disease, injuries, or who have undergone surgery, but no studies have shown them to be effective for healthy people. Because valine cannot be produced by the body, healthy people should ensure that they are obtaining at least the recommended amount in their diet.
Valine can be metabolized to produce energy, which spares glucose. A deficiency may affect the myelin covering of the nerves. Recent studies indicate that valine, as well as leucine and isoleucine, may be effective in treating or reversing hepatic encephalopathy, or alcohol related brain damage. It may also be useful in degenerative neurological conditions. Main food sources of valine are soy flour, raw brown rice, cottage cheese, fish, beef, lamb, chicken, almonds, brazil nuts cashews, peanuts, sesame seed, lentils, chickpeas and mushrooms.
For centuries green tea has been highly valued as a soothing drink to calm the body and soothe the soul. Now new research has discovered the biochemical key to green tea’s deeply soothing effects—the amino acid L-theanine, which is found almost exclusively in the leaves of green tea (Camellia sinensis). L-theanine has been shown to have a deeply relaxing effect, reducing stress and anxiety, but without the sedating effects of other relaxing agents. In fact, many people find L-theanine actually increases energy levels while reducing anxiety.
Researchers have found that L-theanine works by supporting the formation of GABA (gamma-aminobutyric acid), an inhibitory neurotransmitter that blocks the release of the neurotransmitters dopamine and serotonin to promote a state of deep relaxation and calm, while increasing sensations of pleasure.
L-theanine has also been found to directly stimulate the production of alpha brain waves, which are associated with deep states of relaxation and enhanced mental clarity.
In a recent study, Japanese researchers also revealed that—in addition to promoting a deep state of relaxation—L-theanine may also support healthy blood pressure levels, enhance concentration and learning, promote mental clarity and strengthen the immune system.
In human studies L-theanine has been shown to exert profound relaxing effects, 30 to 40 minutes after ingestion, including:
- Relaxation without drowsiness
- Generation of calming alpha-waves
- Improved learning ability, and
- Enhanced sensations of contentment and pleasure