Research Studies - Clinical Proof ( HgH Amino Acids )
Research Studies and Additional Information of the HgH Amino Acids Prove that the
Ingredients Used in the Advanced GHR Platinum Hgh Releasers ( HgH Enhancers ) Truly Work
Dr. LE Dorman, MD - Growth Hormone / Amino Acid Blend
Author of "The Methusaleh Factor"
"As we age, our body stops producing an adequate supply of HGH amino acids. Out of the 191 amino acids in the Growth Hormone chain, GHR Platinum replenishes the body with the needed blend of Stacked HGH amino acids in the Right Ratio and Molecular Weight that helps Stimulate and Restore the Release of your body’s own natural Growth Hormone. Many substances stimulate the release of Growth Hormone from the Pituitary Gland. Amino acids ( from the HGH chain ), drugs and exercise are among the provocateurs." ( Page 35 )
HgH Amino Acid: ARGININE
The amino acid ARGININE works in two major ways in the body:
The first of these it that it is a precursor used to create other compounds. One of these is by converting into Nitric Oxide, a substance which has a pivotal role in certain metabolic processes. Nitric Oxide is then used to help in the control of the flow of blood in the circulatory system. Thus it works as to dilate and relax blood vessels. This then promotes better circulation of the blood throughout the whole body. And that helps to reduce high blood pressure. It also provides a way for more nutrients from food and supplements, as well as oxygen in the blood - to be carried to all of the organs, cells, muscles and tissues of the body. In these ways, Arginine helps support a healthy heart function. Thus, this amino acid could be beneficial in helping to alleviate issues related to Hypertension, diseases of the circulatory system, Angina and Erectile Dysfunction ( ED ).
Additionally, Nitric Oxide is needed to create energy within the cells, and for sending communication signals between the cells to operate. Meanwhile, it also assists in removing waste products ( ie: Ammonia and Lactate ) from the Liver and the muscles, as a result of various activities of cellular metabolism. So in removing these toxic substances, it then helps the muscles, and the entire body, to more quickly recover from physical exercise and strenuous workouts.
The second way that Arginine works is to build proteins. It is also used in digestion to break-down glucose ( sugars ). In this function, it could help improve Insulin Sensitivity. Research studies seem to indicate that in this capacity it might helpful provide relief for people who suffer from the effects of Type 2 Diabetes. It also helps support a healthy Immune System.
One of the health symptoms of the growing older is that quite often, our bodies then do not make enough of this important amino acid Arginine. Or there is a similar problem in that we just do not make it very effectively. Thus, it can become necessary for older people to elevate their day to day amount of Arginine by taking supplements.
Many Research Studies Involving Amino Acids Arginine and Lysine
Over the past thirty years, researchers have conducted a lot of clinical studies to better understand the ways that amino acids affect Human Growth Hormone ( HGH ) levels. This specifically includes Arginine, Lysine and Tyrosine. It is now known by health scientists that raising the levels of these particular amino acids stimulates both the production and release of Growth Hormone ( GH ) from the Pituitary Gland. The GHR Platinum anti-aging HgH Releaser products contain these HGH amino acids along with certain other ones, in these new and improved Doctor-Approved formulas. Here are some examples of these studies, which confirm that these amino acids effectively work as Growth Hormone Releasers ( GHR ).
Acute Effect of Amino Acid Ingestion and Resistance Exercise
on Plasma Growth Hormone Concentration in Young Men
R R Suminski; R J Robertson; F L Goss; S Arslanian; et al
[ Human Performance Laboratory, University of Houston, TX ]
https://pubmed.ncbi.nlm.nih.gov/9063764/
For this multi-part trial, the results tested sixteen men. They participated in four separate tests, which were selected randomly.
In the first test, they were each given a placebo ( which was Vitamin C ). Then they performed a single session of resistance-type exercise.
In the second test, they were each given a dosage of 1,500 mg of L-Arginine and 1,500 mg of L-Lysine together. Right afterwards, they all performed the same single session of resistance-type exercise.
In the third test, they were all given the same dosages of the two amino acids as above, but then did NO exercise ( they simply rested ).
In the final test, they were all given the placebo, and again did NO exercise ( they just rested ).
Throughout, the researchers obtained measurements of Growth Hormone levels at intervals of 30, 60 and 90 minutes during the two exercise sessions ( Tests 1 & 2 ). They compared the data results with the two resting trials ( Tests 3 & 4 ). There were NO differences noticed in Growth Hormone levels between the exercise trials.
Results of the Study and Conclusions
The researchers observed that resistance exercise can raise the levels of Growth Hormone in the human body. However, taking the amino acids right before doing the exercises did not help, and did not stimulate, any possible additional increase in GH levels, which the exercises would normally produce.
However, when the same mix of these two amino acids was given in normal resting conditions, there was clearly an acute secretion ( release ) of Growth Hormone.
Increased Human Growth Hormone Following Oral Consumption
of an Amino Acid Supplement: Results of a Randomized,
Placebo-Controlled, Double-Blind, Crossover Study in Healthy Subjects
Am J Ther - Manuscript Author
https://pmc.ncbi.nlm.nih.gov/articles/PMC6732240/
In this study, the researchers wrote that is is confirmed ( by many clinical trials ) that application of certain amino acids causes a huge increase in the secretion of HgH from the pituitary gland. Those studies motivated them to test some of these amino acids. They support that certain of these, mainly Arginine, Lysine and Orthinine ) can stimulate release of Growth Hormone.
For this reason, both Arginine and Lysine are included in this Hgh Amino Acids Complex of GHR Platinum products.
Growth Hormone Responses to Varying Doses of Oral Arginine
Scott R Collier; Darren P Casey; Jill A Kanaley
https://pubmed.ncbi.nlm.nih.gov/15809017/
Here, the researchers observed that dosages of just 5 grams and 9 grams of Arginine given orally were able to produce a large response in the levels of Growth Hormone.
Growth Hormone, Arginine and Exercise
Jill A Kanaley - Author
[ Department of Exercise Science, Syracuse University, Syracuse, New York ]
https://pubmed.ncbi.nlm.nih.gov/18090659/
The researcher observed from various studies and clinical trials that the administration of oral Arginine by itself, increases resting levels of Growth Hormone, by at least 100%.
A Study of Growth Hormone Release in Man After Oral Administration of Amino Acids
A Isidori; A Lo Monaco; M Cappa
https://pubmed.ncbi.nlm.nih.gov/6790230/
In this clinical study, the researchers evaluated fifteen 15 men concerning various factors that might affect the release of Growth Hormone using oral amino acids. The test data from their trial demonstrated that the combination of two specific amino acids - 100 mg each of Arginine and Lysine stimulated a release of Pituitary Somatotropin { which is related to release of GH } and Insulin.
They were able to repeat their test and obtain the same results. They concluded that the outcome appeared to be directly connected to using these two particular amino acids together.
HgH Amino Acid: LYSINE
Lysine is one of the eight essential amino acids. These are the ones which we can not make on our own. Thus, we need to obtain them from protein foods that we consume. Or in the alternative, we have to get them from supplements which have them in readily-available forms that our bodies can use.
Lysine is one of the most crucial amino acids there is, since it is required to build proteins in the body. It is also important for making muscle tissues, and to also to create hormones, enzymes and anti-bodies. Additionally, it plays a significant role in enabling the body to absorb the mineral Calcium, while helping to reduce the loss of calcium in urine. Finally, it also helps to lower Cholesterol levels.
Like the amino acid Glutamine ( see next section below ), it helps the body to heal and repair tissues and cells and recover from injuries and wounds. It acts as a Binding Agent, to help increase the number of new cells in an injury or wound that is healing. Together with the amino acid Glycine, it is required to form Collagen, that is used to form skin, nails, hair, and various connecting tissues in the body.
It is a precursor to L-Carnitine, which is a derivative of amino acids, and found in most cells of the body. This substance is important to enable the nervous system to function properly. Lysine is likewise a precursor for the compound L-Carathine, that is similarly required to maintain a healthy nervous system.
Carnitine carries Long-Chain Fatty Acids across the Mitochondria of cells and then consumes them to create energy for metabolism. Afterwards it then removes the toxins, created from the metabolic processes, out of the cells. Lysine is also critical for normal physical growth. So, a lack in the amount of Lysine can lead to all kinds of health issues and problems, such as dizziness, nausea, fatigue and slowed physical growth.
Three of the research studies above included testing of both Arginine and Lysine. These, along with many other similar clinical studies, prove that Lysine is likewise a Growth Hormone Releaser ( GHR ).
HgH Amino Acid: GLUTAMINE
The amino acid Glutamine is a vital amino acid which supports a healthy functioning of the brain. It is required for the synthesis of both RNA and DNA in the body. It promotes the release of Growth Hormone ( GH ) that starts a process in the body that is called "NeuroGenesis", which how new brain neuron cells are created. So this amino acid supports the maintenance and functioning of existing brain cells.
Likewise the levels of GH also affect the levels of brain Neuro-Transmitters. Glutamine is a powerful amino acid that is also a precursor for the making of the NeuroTransmitters GABA and Glutamate. These brain neuro-tansmitters also help to manage and support various cognitive functions, including mood, memory and concentration. GABA is a special amino acid that is also included in the formula of the GHR Platinum supplements in the Hgh Enhancers Complex.
Various clinical studies have shown that even small dosages of Glutamine can cause a noticeable boost in the levels of Growth Hormone in the body. For instance, some research studies have demonstrated that just 2 mg of this powerful amino acid could temporarily raise the levels of Human Growth Hormone ( HGH ) by as much as 78%. How does Glutamine work to cause more release of your GH? The NeuroTransmitter Glutamate plays a huge part in activating the Somatotroph cells in the the Pituitary Gland. These are the special cells that then stimulate the creation and release of Growth Hormone.
Glutamine is also a precursor to make the amino acid Arginine, that has already been explained above. We have seen from those studies presented, that it is clinically proven to cause the Pituitary Gland to raise the production and secretion of Growth Hormone. Therefore, when you increase your intake of Glutamine, you also allow your body to raise the levels of Arginine, as well as the two neuro-transmitters GABA and Glutamate as well.
Glutamine is the most abundant amino acid found in the blood and fluids of the body. It has many significant functions. It is used to build proteins, as well as create energy, and help with detoxification and removal of waste products ( Ammonia ), from metabolic processes.
Also, Glutamine is necessary for a healthy Gastro-Intestinal Tract ( GI Tract ). It provides energy for white blood cells in the Immune System, and for the growth and maintenance of certain specific cells in the Intestines. It helps to maintain the barrier that separates the inside of the Intestines and the rest of the body. In this way, it helps you to have a healthy gut. This protects you from a "Leaky Gut". So in this capacity, it supports a healthy and strong Immune System.
There are some situations or circumstances that cause the amount of Glutamine to become diminished. These include
when there is lot of stress, or sickness, illness or severe injury. In those occasions, the body generally needs more of this amino acid for the healing, repair of damaged tissues and cells and the recovery process. But when the body cannot make enough Glutamine, it must then obtain it from elsewhere. So the body might then break down muscles tissues to release proteins.
When someone is going through a high level of stress, the body will release a greater amount Cortisol. This is called as the "Stress Hormone". There a link between stress and Hgh levels in the body. Scientists known that excess Cortisol can block the production of Growth Hormone. So, if can lower the amount of stress you have, you can also reduce the amount of Cortisol which blocks the production and release of the very GH that you need and want to increase.
There is also a very strong relationship between fat burning and Growth Hormone secretion. Part of this connection is that Human Growth Hormone actually helps to breakdown fats, through the process of "Lipolysis". In this way, fats other lipids are converted to Fatty Acids. Likewise, there is a similar link between the metabolism of carbohydrates and Growth Hormone. And this has a direct affect on levels of blood sugar.
So Glutamine is involved in important ways in the digestion process in converting starches, sugars and fats into usable energy for the multitudes of metabolic activities in the body. So in an indirect way, this amino acid then has a large affect on weight loss. Consequently it is necessary to keep adequate levels of both Glutamine and Arginine. And because both of these amino acids are involved in causing the production and secretion of GH, both of them provide important health benefits - physically, mentally and emotionally.
Clinical studies have proven that high levels of BODY FAT, especially around the waist ( BELLY FAT ), actually block and limit the production and release of Growth Hormone. Thus, the amount of fat ( Adipose Tissue ) which people carry around in their bodies, particularly in their bellies, will greatly influence the ability of their bodies, in an adverse way, to produce of adequate amounts of GH. As a result, if a person can lose extra weight, especially belly fat, then that can also help them to boost their HGH output. And so among the many health benefits of using GHR Platinum products, it can also help you to lose excess weight.
Increased Plasma Bicarbonate & Growth Hormone After Oral Glutamine Load
Welbourne, TC ( Department of Physiology, Louisiana State University College of Medicine, Shreveport, LA )
https://pubmed.ncbi.nlm.nih.gov/7733028/
In this study, nine healthy volunteers were given an oral load of the amino acid Glutamine. The researchers wanted to test the effect on concentrations of plasma Glutamine, bicarbonate, and circulating Growth Hormone levels.
These results of their findings demonstrated that a very small amount of Glutamine is capable of raising alkaline reserves, as well as plasma Growth Hormone levels in the body.
HgH Amino Acid: GLYCINE
Glycine is the second most common amino acid in the body. It is needed to create various proteins. It is also the most abundant of the amino acids used to create Collagen. Collagen is required for the making of nails, skin, hair and various connective tissues in the body. This amino acid also helps in creating muscles ( and energy in the muscles ), bones, and supporting a proper functioning of the brain, including healthy sleep patterns.
Glycine is one of the three amino acids used in making the Tri-Peptide Glutathione ( an AntiOxidant which is found in the cells ). This substance is created from the three ( 3 ) amino acids: Glutamic Acid, Cysteine, and Glycine.
One of the symptoms of growing older, is that our bodies often have a reduced ability to make
this anti-oxidant Glutathione. Thus we probably need to take a supplement to obtain enough of it.
Glutathione helps the body prevent damage and disease to organs ( especially the Liver ), tissues and cells, which Free Radicals can cause. If the liver gets damaged, it can form fibrous tissues, that then become scarred. Or the liver could become diseased through the build up of excessive fat, which is a condition called "Fatty Liver". Excessive consumption of alcohol, and various immune attacks, can also cause damage to the liver.
The amino acid Glycine also functions as a brain NeuroTransmitter. In this way, it works to support the processing of motor and sensory information, which provides for movement, vision and hearing. It also works by helping to calm the central nervous system.
During times of high levels of stress, sickness or injury, our bodies need more Glycine, just like we need more Glutamine. And the reason is the same - to repair and restore tissues and cells and aid in the healing of wounds. But in such times, our bodies are sometimes not able to make enough of this crucial amino acid.
Finally, this amino acid also is involved in the digestive function. It helps in the process of breaking down fats by managing the secretion of bile acids from the Gall Bladder into the Small Intestine. At the same time, it also functions in the capacity as a "Glucogenic Amino Acid". This means that the liver can convert it into glucose ( sugar ).
There have been many clinical studies that demonstrate the connection between Glycine levels and those of Human Growth Hormone. Here are some of these:
Reduced Plasma Glycine Concentration in Healthy and Chronically Diseased
Older Adults: a Marker of Visceral Adiposity { Fat }?
Lars Nj Deutz; Raven A Wierzchowska-McNew; Nicolaas Ep Deutz; Mariëlle Pkj Engelen
[ Center for Translational Research in Aging and Longevity,
Department of Kinesiology and Sport Management, Texas A&M University, College Station, TX ]
https://pubmed.ncbi.nlm.nih.gov/38616018/
At the start of this research study, the researchers stated the following. Prior studies have demonstrated that a lower plasma concentration of Glycine is related to obesity in the abdomen area ( which would include the waist ). However the way that this occurs remains unknown.
In this study, they wanted to investigate whether reduced levels of Glycine in older adults are independently connected to any of the following factors - visceral adiposity ( fat ), age, gender, existence of chronic disease, and glucose intolerance, and various other conditions. Moreover, they wanted to determine certain other potential causes of lower concentrations of Glycine.
They took 102 older men ( 47 ) and women ( 55 ). They evaluated body composition and adiposity tissue. As a result of their tests, they observed that higher levels of adiposity ( fat mass ) in older people was unrelated to any of the factors mentioned above. Thus they concluded that diminished levels of Glycine can be considered as an indicator of visceral adiposity in the body, regardless of any of those factors they considered.
Glycine Stimulated Growth Hormone Release in Man
K Kasai; H Suzuki; T Nakamura; H Shiina; S I Shimoda
https://pubmed.ncbi.nlm.nih.gov/7376793/
In this clinical study, the researchers tested the impact of administering different amounts of Glycine on the participants.
They gave three different dosages of Glycine ( 4, 8, and 12 grams ), intravenously, over a period of 15 to 30 minutes
They observed the following. The application of both 4 grams and 8 grams of the infusion stimulated an increase in serum GH levels. However, a more acute and significant elevation of GH was seen from applying the dose of 12 grams.
Therefore, they concluded that Glycine could play an important part in the regulation of the functions of the Hypothalamus and the Pituitary Glands.
Stimulatory Effect of Glycine on Human Growth Hormone Secretion
K Kasai; M Kobayashi; S I Shimoda
https://pubmed.ncbi.nlm.nih.gov/622050/
Here the researchers provided an oral dosage of Glycine to 19 non-obese healthy subjects, as well as to 12 participants with partial gastrectomy. In the first group ( of normal subjects ), they observed a positive and notable improvement in Growth Hormone levels.
Thus they concluded that Glycine is capable of inducing the Pituitary Gland to secrete HgH.
The Effect of Glycine Administration on the Characteristics
of Physiological Systems in Human Adults: A Systematic Review
Janjira Soh; Shivaanishaa Raventhiran; Jasinda H Lee; Zi Xiang Lim; Jorming Goh; Brian K Kennedy; Andrea B Maier
https://pubmed.ncbi.nlm.nih.gov/37851316/
At the beginning of this study, the researchers noted the following. There is a decline of bodily systems and functions as people get older. This leads to age-related diseases. The amino acid Glycine increases healthy lifespan and could also help to lower inflammation. This suggests that it might play a role in helping to prevent such old-age diseases.
Their review of prior research studies summarized the available evidence concerning effects that an administration of Glycine has on eleven biological systems in adults. The most positive effects were demonstrated in the nervous system. This included improved psychiatric ( mental ) symptoms from longer-term use of Glycine. Additionally, such use also enhanced sleep in healthy adult humans.
HgH Amino Acid: TYROSINE
The amino acid Tyrosine is a derived from Phenylalanine, which itself is one of the eight essential amino acids. Thus, if we lack adequate amounts of Phenylalanine, we will also be deficient in Tyrosine as well. So, we need to eat enough proteins in our diets that contain it. Otherwise, we need to get more of it by taking supplements.
Tyrosine is needed to make a number of proteins and protein-based compounds. This includes the hormones produced in the Thyroid Gland ( ie: Thyroxin ), which helps to manage metabolism, the hormones of the Adrenal Cortex, Melanin ( a color pigment found in the hair, skin and iris of the eyes ), enzymes, and also various neuro-transmitters in the brain.
These neuro-transmitters are related to our cognitive abilities, which include: focus, concentration, memory and working memory, mood, cognitive flexibility ( the ability to switch between two or more mental tasks or change thoughts ) and following instructions.
Tyrosine is also a precursor for the NeuroTransmitters / Hormones - Dopamine, Epinephrine, Norepinephrine, Adrenaline and Noradrenaline. Each of these substances can have an impact the release / secretion of HgH in the Pituitary Gland.
Dopamine is critical for our mood and various mental functions. It regulates the reward and pleasure centers in the brain. This important substance is also crucial for memory and motor ( movement ) skills.
Adrenaline and Noradrenaline are hormones that are needed in what is called the "Fight-or-Flight Response" in stressful circumstances. They enable us to stand and fight, or flee and run - from an actual attack or perceived harm.
In these various ways, the amino acid Tyrosine helps us to balance the affects of both physical and mental stress. When we are under a burden of stress, we sometimes have difficulty thinking clearly and remembering things. Research studies have shown that Tyrosine supplementation can help support and improve cognitive abilities in such conditions. Various research studies that have been performed, have shown that it also helps to lower anxiety and stress levels, and aids us to be more alert mentally.
Likewise, Tyrosine has a role in the formation of other special compounds in the brain called "Enkephalins". These are substances which carry pain-relieving effects to the body. They also transmit nerve impulses and signals, and prevent conditions such as depression. So they are critical to healthy brain functioning.
Additionally, this amino acid also has a part in the management of blood pressure. And like some other amino acids, it also is used to help reduce BODY FAT. As we explained earlier, excess body fat, particularly BELLY FAT, inhibits and blocks the production of HGH. And finally, this amino acid also works an AntiOxidant, helping to protect the body from damage that Free Radicals can cause to organs, tissues, muscles and cells.
There are many research studies that have been conducted to discover more about how Tyrosine affects the ability of the Pituitary Gland to secrete Growth Hormone. There may be an increase in the release of our GH at particular times, particularly in periods of stress.
One particular research study found out that Tyrosine has a significant role in supporting higher levels of both HGH and IGF-1 ( Insulin Growth Factor - 1 ), particularly in times of much stress, or intensive physical workouts. Researchers believe that it works by activating Tyrosine Kinase, an enzyme which functions as a messenger, to signal the Pituitary Gland to begin certain metabolic processes that are connected to the production and release of GH.
Meanwhile, clinical studies show that Tyrosine becomes more effective at boosting Human Growth Hormone levels, when it is combined with the two specific amino acids Arginine and Lysine. As explained earlier, there is so much research already that clearly proves the ability of these two specific amino acids to increase HGH levels. So when Tyrosine is then also introduced, there is a further increase in the production and release of Growth Hormone.
Tyrosine Promotes Cognitive Flexibility: Evidence From Proactive vs. Reactive Control
During Task Switching Performance
Laura Steenbergen; Roberta Sellaro; Bernhard Hommel; Lorenza S Colzato
( Institute for Psychological Research, Leiden University, Leiden - Netherlands )
https://pubmed.ncbi.nlm.nih.gov/25598314/
The amino acid Tyrosine ( TYR ) has been demonstrated in studies to elevate levels of Dopamine ( DA ) in the brain. Recent studies have presented evidence that supplementation with TYR can improve various aspects of cognitive control in situations that have greater demands for mental processing.
In a Double-Blind, Randomized, Placebo-Controlled design, the researchers evaluated 22 healthy adults. In this research study, they investigated whether a Tyrosine dosage supports improved cognitive flexibility, a cognitive-control function which is presumed to be regulated by Dopamine. They examined the effects of using this amino acid on task-switching performance ability in a proactive versus reactive condition. This test provided a comparatively well-established marker of cognitive flexibility.
Results of this Clinical Study
The administration of the Tyrosine dose indeed encouraged improved cognitive flexibility, compared to the use of the placebo. This result supports the hypothesis that increasing levels of Tyrosine can facilitate cognitive flexibility by supplying cognitive resources when needed.
Increased Human Growth Hormone Following Oral Consumption of an Amino Acid Supplement: Results of a Randomized, Placebo-Controlled, Double-Blind, Crossover Study in Healthy Subjects
Charmaine S Tam; William D Johnson; Jennifer Rood; Amy L Heaton; Frank L Greenway
https://pmc.ncbi.nlm.nih.gov/articles/PMC6732240/
This was a Randomized, Double-Blind, Placebo-Controlled, Crossover Study which included 16 healthy participants ( 12 males and 4 females ; age 32 years old ±14 years ). The researchers wanted to investigate the effects of administering a supplementation of Tyrosine on the release of HgH from the Pituitary Gland.
All of the volunteers received both the placebo and the amino acid supplement, after an overnight fast. Each of them also completed all study visits. The treatment order was randomized. Each treatment was separated by a one-week washout period.
The primary outcome was the percent change in Growth Hormone levels from baseline to 2 hours and the Area Under the Curve ( AUC ) of HgH over baseline. At 120 minutes, the levels had increased by 682% ( 8-fold improvement ) from baseline. Clearly these were remarkably much higher than in those using the placebo. In addition, a significantly higher mean AUC was observed for the amino acid supplement compared to placebo.
These results of the study demonstrated that a single dose of the oral amino acid Tyrosine was enough to cause a substantial increase Human Growth Hormone levels in healthy adults.
Effect of Tyrosine Supplementation on Clinical and Healthy Populations
Under Stress or Cognitive Demands - A Review
Bryant J Jongkees; Bernhard Hommel; Simone Kühn; Lorenza S Colzato
( Institute for Psychological Research & Leiden Institute for Brain and Cognition, Leiden University, Leiden, Netherlands
and Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany )
https://pubmed.ncbi.nlm.nih.gov/26424423/
Based on the results of this study, the researchers determined that taking more amounts of Tyrosine, the precursor of both Dopamine ( DA ) and Norepinephrine ( NE ) might counteract decreases in levels of these neurotransmitters and cognitive capabilities. In this review, they examined the available studies on behavior and cognition, involving the use of Tyrosine, to determine when supplementation can benefit cognitive performance.
They concluded that Tyrosine does appear to positively enhance cognitive abilities, particularly in short-term stressful conditions and / or in situations requiring more cognitive resources. They concluded that this amino acid improves cognition / mental performance, but only when neuro-transmitter function is in place and levels of Dopamine and / or Norepinephrine are temporarily depleted.
Tyrosine Hydroxylase Neurons Regulate Growth Hormone Secretion
via Short-Loop Negative Feedback
Frederick Wasinski; João AB Pedroso; Willian O dos Santos; Isadora C Furigo; David Garcia-Galiano
https://pubmed.ncbi.nlm.nih.gov/26424423/
At the start of this clinical study, the researchers noted that various research studies have indicated that the release of Human Growth Hormone is regulated by negative-feedback loops that are controlled by several growth hormones working together. Two of these in particular include Growth Hormone - Releasing Hormone ( GH - RH ) and Somatostatin ( SS ) neurons in the brain.
The researchers concluded that the modulation of the secretion of HGH depends on the capacity of these brain neuron cells to detect changes in the levels of circulating Growth Hormone. Consequently, their investigation named a specific group of Tyrosine Hydroxylase-Expressing Neurons which are vital for the brain to self-regulate the release of GH through a negative-feedback loop.
Behavioral and Cognitive Effects of Tyrosine Intake in Healthy Human Adults
Adrian Hase; Sophie E Jung; Marije aan het Rot
( Department of Psychology, University of Groningen, Netherlands )
https://pubmed.ncbi.nlm.nih.gov/25797188/
At the start of this research study, the researchers noted that Tyrosine is the precursor to the catecholamine ( Tyrosine-based ) NeuroTransmitters Dopamine and Norepinephrine. Boosting levels of this amino acid may effectively influence related mental abilities and functioning.
They conducted a systematic review to evaluate the effects of Tyrosine on behavior and cognition. They examined fifteen research studies. All of these studies, except for one, involved a Tyrosine load used during a single test session. In most behavioral studies, there were no significant effects of Tyrosine on exercise performance.
In contrast, however, studies on cognition, using neuro-psychological measurements discovered that Tyrosine loading sharply counteracts decreases in both information processing ( IP ) and working memory ( WM ), that are induced by various situations and conditions demanding extreme mental resources.
They concluded that the mitigating effects of a Tyrosine load on mental performance could be explained by its ability to
neutralize depleted brain catecholamine levels. There is evidence that the amino acid Tyrosine may benefit healthy individuals exposed to demanding situational conditions.
Working Memory Reloaded: Tyrosine Repletes Updating in the N-Back Task
Lorenza S Colzato; Bryant J Jongkees; Roberta Sellaro; Bernhard Hommel
( Institute for Psychological Research, Leiden Institute for Brain and Cognition, Leiden University, Leiden, Netherlands )
https://pmc.ncbi.nlm.nih.gov/articles/PMC3863934/
In this study, the researchers tested the concept that L-Tyrosine supplies mental resources required for cognitive-control functions. This particular study focused on whether certain aspects of updating ( and monitoring ) of working memory, a key component of such mental functioning, could be improved by administering a dosage of this amino acid, which is known to be the precursor of Dopamine.
It appears that they were surprised to find out that there is an interplay between cognitive stability ( defined as the maintenance of task-relevant representations ) and cognitive flexibility ( defined as the ability to adapt, update, and shift between informational states ). These are two major mental functions, although they are partially antagonistic to each other. Both are managed by Dopamine.
They investigated the link between Tyrosine and the monitoring of WM in healthy adults, using an amino acid dosage and a placebo.
They concluded the following from their trial results. This was the first study to demonstrate that Tyrosine supplementation promotes updating in cognitive working memory. Moreover, as they had anticipated, the more challenging the mental conditions were, the more sensitive the study participants were to the effect of the increased Tyrosine level. This then reinforced their expectation that only tasks with considerable cognitive demands benefit from Tyrosine. This may be due to the fact that more demanding cognitive control functions are more likely to exhaust the available cognitive resources, that can then be provided by more Tyrosine uptake.