THE SCIENCE BEHIND AMINO
Drinks backed by 40 years of research
Combining the latest nutrition technology and years of clinical research, Amino creates delicious drinks with blends of amino acids designed to deliver amazing functional benefits for active lifestyles.SHOP AMINO
The power of amino acids
What are amino acids?
You may have heard nutritionists talk about “macronutrients” or “macros”. These are the carbohydrates, fats and proteins found in the food you eat.
Protein is in fact constructed from smaller molecules called amino acids. Amino acids build the proteins that make up your tissues and organs and are involved in virtually every cellular process, from muscle growth to the creation of neurotransmitters and other essential biochemicals.
What are essential amino acids (EAAs)?
There are 20 different amino acids, all of which play an important role in our bodies. 11 of them can be found in our diets and can be made by our bodies. These are called non-essential amino acids (NEAAs) because you don’t need to get them from external sources.
The other 9 are essential amino acids, so-called because the body cannot produce them. You must get these amino acids from your diet or supplements.
What are branched-chain amino acids?
Of the 9 essential amino acids, 3 (leucine, isoleucine, and valine) are also "branched-chain amino acids". That’s because they’re the only amino acids that have a chain that branches to the side.
As with other essential amino acids, branched-chain amino acids (BCAAs) are important for energy and muscle metabolism. However, there is little evidence that they can stimulate muscle protein synthesis on their own. Research suggests that BCAAs are most useful when consumed alongside other EAAs.
How are protein and amino acids related?
Proteins are made of amino acids, so you can see why the two are easily confused.
You can think of proteins as buildings; they’re made up of thousands of amino acid building blocks. Our digestive systems take these building blocks apart to build other useful substances.
There are many different types of protein molecules, each containing a vastly different arrangement of amino acids. Some proteins from foods provide your body with very few benefits, while others are extremely useful.
High-quality protein that’s packed with all 9 essential amino acids will have a positive impact on your training performance and help you get the physical results you’re after.
Understanding the importance of amino acids
Your body is constantly repairing
Protein synthesis refers to the process of building new protein molecules. Every muscle, organ and tissue in your body is in a constant state of protein breakdown and synthesis. If you want to maintain or grow your lean body mass, you should seek ways to boost protein synthesis.
You need amino acids to stay healthy
The body uses amino acids circulating in the bloodstream to build proteins. If there aren’t enough amino acids in the blood, muscle tissue is broken down to release amino acids into the blood and carry out the rebuilding process.
Essential amino acids need to be consumed
Because your body cannot produce essential amino acids, they must be consumed through food or supplements. If you don’t give your body a consistent supply of essential amino acids, you lose the ability to maintain muscle mass and bone density. Your health may suffer as a result.
What do Amino acids do?
Build, repair, regulate, energise
Amino acids are commonly known for their role in muscle protein synthesis. However, the benefits stretch beyond your workout and muscles.
Amino acids make proteins, which make up about 20% of our bodies. Our skin, hair, muscles, internal organs, red and white blood cells all depend on proteins for structure and function. Amino acids also help regulate and maintain most bodily processes by becoming proteins, enzymes or hormones, and by supplying energy to our cells.
Cognitive function & nervous system
The central nervous system controls most bodily functions and our minds. It consists of two parts: the brain and the spinal cord. To function adequately, the brain and central nervous system need a number of amino acids, including histidine, tryptophan, tyrosine, and arginine. The brain uses these to produce various neurotransmitters and neuromodulators.
Simply put, hormones are signalling molecules and they encourage the body to respond to stimuli. Hormones raise our blood pressure during exercise, allow us to sweat when we're hot and more. Amino acids can either be used as building blocks for specific hormones or to encourage the release of hormones.
There is evidence that the amino acids lysine and arginine help to trigger the release of growth hormones, encouraging the growth and development of cells, which can be particularly useful for children and sports people looking to gain muscle mass.
Amino acids are the major fuel of the small intestine membrane and they are also used to support the intestinal immune and anti-oxidative responses. Glutamate, glutamine and aspartate, in particular, are vital. You may have heard the phrase that your gut is your first line of defence against disease and pathogens and amino acids play a major role in these defenses.
The availability and metabolism of amino acids, which interact with other macronutrients, is vital for various reproductive processes, including gametogenesis, fertilisation, implantation, placentation, foetal growth and development.
The immune system protects your body from outside invaders, such as bacteria, viruses, fungi, and toxins. The system is made up of different organs, cells and proteins that work together.
A deficiency of dietary protein or amino acids impairs immune function and increases susceptibility to infectious disease. That’s because protein is broken down to provide amino acids for the creation of new cells, proteins and peptides, vital for the immune response. Amino acids can be used as fuel by the immune system either directly, or following their conversion to other amino acids (e.g., glutamine) or to glucose for energy.
Mounting evidence shows that giving specific amino acid supplements to animals and humans with malnutrition and infectious disease improves the immune response. Arginine, glutamine and cysteine precursors are the best used examples in recent studies.
How can amino acids help your workout?
During workouts and intense training, our muscles need more amino acids. To meet the increased demand, athletes and fitness enthusiasts often supplement with essential amino acids (EAAs) during a workout. Studies show that, alongside building muscle, they can reduce workout fatigue and decrease muscle soreness after exercise.
Supplementing with amino acids also has a few other benefits. Supplements are absorbed faster than food because they don’t need as much processing by our digestive systems, meaning they reach our muscles more quickly. Although they’re less complete, they have a different impact on our metabolism and they don’t affect your calorie intake. That’s especially helpful if you’re trying to cut calories.
Essential amino acids and your fitness journey
To build muscle
You're an aspiring bodybuilder or gym-goer looking to incorporate amino acids into your routine to build muscle mass and size.
Eat more calories
A calorie excess diet strategy is the most essential part of building muscle, but amino acids are the building blocks of your body and of the new muscle you want to grow.
The essential amino acid leucine is especially important for stimulating protein synthesis.
EAA drinks are absorbed faster than protein formulations, rapidly increasing blood amino acid concentrations.
Yes, you can get amino acids from the protein you consume but research has shown that taking an essential amino acid supplement alongside exercise triggers muscle protein synthesis to a clinically significant degree, even in people with high-protein diets.
Drink during your workout
By targeting the delivery of essential amino acids (including leucine) when your muscles need them (i.e. during your workout) you can maximise your results. The rapid delivery of EAAs to tissue will switch on and sustain protein synthesis.
Regulation of Muscle Protein by Amino Acids.
The Journal of Nutrition, WOLFE, R. (2002).
The aim of this study was to consider the way in which ingested protein and energy intake affect the rate of muscle protein synthesis (MPS) in different circumstances than to try to identify a particular numerical value for requirement.
The results showed that essential amino acid (EAA) availability / concentrations regulate muscle protein metabolism - the synthesis and breakdown of muscle proteins - in human subjects. The magnitude and duration of the response is directly affected by the exact composition and amount of mixture of amino acids ingested, the timing of ingestion in relation to exercise and the amount and nature of nonprotein energy (i.e. carbohydrate) ingested with the EAAs.
Latency, Duration and Dose Response Relationships of Amino Acid Effects on Human Muscle Protein Synthesis.
The Journal of Nutrition, RENNIE, M., et al. (2002).
Researchers wanted to obtain information about the latency and duration of the amino acids' stimulatory effect, and then, having obtained this information, to measure the dose response of muscle protein synthesis to amino acids supplied during the time of their maximal efficacy.
The results suggested that there is a limit the amount of protein that can be stored in muscle. Thus, it makes no sense to supply more than the amount required to cause a “muscle full” situation. Calculations showed that amounts of amino acid as small as 3.5 g given on a single occasion would result in this “muscle full” situation. This did not take into account the amounts of amino acid obtained by dietary protein during feeding.
Effect of a leucine-enriched essential amino acids mixture on muscle recovery.
The Journal of Physical Therapy Science, MATSUI, Y., et al. (2019).
The aim of this study was to determine whether the consumption of a leucine-enriched essential amino acid mixture (LEAA), which is known to increase protein synthesis in muscles, alleviates muscle damage and accelerates recovery by ameliorating muscle damage.
This study found that leucine-enriched essential amino acid mixture (LEAA) consumption suppressed exercise-induced elevation of muscle damage markers in blood, which suggests that LEAA could reduce muscle damage and aid muscle recovery.
Stimulation of net muscle protein synthesis by whey protein ingestion before and after exercise.
American Journal of Physiology-Endocrinology and Metabolism, TIPTON, K., et al. (2006).
This study was designed to examine the response of muscle protein balance to ingestion of whey proteins or essential amino acids both before and following resistance exercise.
Taking EAAs prior to exercise was shown to be over 3 times more effective in stimulating muscle synthesis than whey protein.
Essential amino acids and muscle protein recovery from resistance exercise.
American Journal of Physiology-Endocrinology and Metabolism, BØRSHEIM, E., et al. (2002).
Researchers tested the effects of a 6-gram dose of orally administered essential amino acids (EAAs) on net muscle protein balance in healthy, young volunteers when taken 1 and 2 hours following resistance exercise.
Researchers concluded that there is a dose-dependent stimulation of net muscle protein synthesis by EAAs after exercise, and that consumption of nonessential amino acids (NEAAs) is not necessary.
Activation of mTORC1 by leucine is potentiated by branched-chain amino acids and even more so by essential amino acids following resistance exercise.
American journal of Cell Physiology, MOBERG,M., et al. (2016).
To determine if BCAAs have a greater effect on mTORC1 signaling and protein synthesis than EAAs or leucine alone when taken after resistance exercise.
The oral supplementation with BCAA following resistance exercise stimulates mTORC1 signalling more potently than ingestion of leucine alone, but not as effectively as EAA. In other words, EAA > BCAA > Leucine alone for building muscle.
Functional Amino Acids in Growth, Reproduction, and Health.
Advances in Nutrition, GUOYAO, W. (2010).
A literature review into the regulatory roles of amino acids in nutrition and metabolism. Traditionally all non-essential amino acids were assumed to be synthesised adequately in the body as substrates to meet the needs for protein synthesis. Conceptual limitations in the availability of non-essential amino acids were not recognised until recently.
A growing body of literature leads to a new concept of "functional amino acids", which are defined as those amino acids that regulate key metabolic pathways to improve health, survival, growth, development, lactation, and reproduction of organisms. Both non-essential and essential amino acids should be considered in the balanced diets to maximise amino acid availability and optimise health in animals and humans.
To lose fat
You're into fitness and want to use amino acids to get lean and decrease body fat.
A calorie deficit diet strategy is key for dropping excess body fat. However, exercise-induced calorie deficits pose a risk for lean tissue, because your body burns muscle mass at the same rate as fat.
EAAs are very effective at preventing muscle wastage while making sure you have appropriate protein in your diet.
Muscle tissue uses more energy than fat tissue, so as you build muscle, your metabolism revs up and you burn more calories.
In a single-blind, matched group design: branched-chain amino acid supplementation and resistance training maintains lean body mass during a caloric restricted diet.
Journal of the International Society of Sports Nutrition, DUDGEON, W.D., et al.(2002).
Losing weight by caloric restriction in combination with exercise poses a risk for lean tissue loss and performance limitations. The purpose of this study was to determine the effectiveness of a branched-chain amino acid (BCAA) supplement, in conjunction with heavy resistance training and a carbohydrate caloric-restricted “cut diet” on body composition and muscle fitness.
The results showed that BCAA supplementation in trained individuals performing resistance training while on a hypo-caloric diet can maintain lean mass and preserve skeletal muscle performance while losing fat mass.
Amino acid supplementation increases lean body mass, basal muscle protein synthesis, and insulin-like growth factor-I expression in older women.
Journal of Clinical Endocrinology and Metabolism, DILLON, E.L., et al. (2009).
Inadequate dietary protein intake has been implicated in sarcopenia. The objectives of this study were to determine whether essential amino acid (EAA) supplementation improves muscle protein synthesis rate (MPS), lean body mass (LBM), and one-repetition maximum muscle strength, and androgen receptor and IGF-I muscle protein expression.
EAA improved lean body mass and basal muscle protein synthesis in older individuals. The acute anabolic response to EAA supplementation is maintained over time and can improve lean body mass, possibly offsetting the debilitating effects of sarcopenia.
Plasma and muscle amino acid and ammonia responses during prolonged exercise in humans.
Journal of Applied Physiology, MACLEAN, D.A., et al. (2000).
To measure the plasma and muscle amino acid (AA) and ammonia (NH3) responses measured prolonged sub-maximal exercise in humans.
Six men cycled at 75% of maximal O2 uptake until exhaustion on two occasions after 2.5 days of ingestion of a high-carbohydrate or mixed diet. Plasma samples and muscle biopsies were obtained at rest and during exercise and analysed for plasma and muscle NH3 and AA as well as muscle metabolites. There were no significant diet effects in these parameters, so the majority of results focus on the effects of exercise.
The results suggested that protein catabolism (breakdown) was occurring during exercise and the branched-chain amino acids were used for energy and ammonia production.
To perform better
You're an athlete pushing your body to the limit and want to use amino acids to boost your performance.
Recover better to perform better
Whether your sport is endurance, sprint or power-based, you only get better, stronger and fitter in the recovery periods after your training sessions. Not during.
EAAs won't stop you burning out if you're over-training but they will support your recovery process, especially as you age.
Preserve lean muscle mass
EAAs help to support the muscle and hormone recovery process, preventing the degradation of the body, especially when pushing yourself to the limit.
Eat more, sleep more
The two biggest factors for recovery are nutrition and sleep.
Studies show that active individuals benefit from diets containing more amino acids and protein than individuals with sedentary lifestyles.
Easy on the digestion
EAAs are absorbed more rapidly than dietary proteins.
This makes them the ultimate choice to drink while you train, so you avoid post-training bloat, especially if you have a digestive disorder.
Do athletes need more dietary protein and amino acids?
International Journal of Sport Nutrition and Exercise Metabolism, LEMON, P.W. (1995).
The recommended daily allowance (RDA) for protein is based primarily on data derived from subjects whose lifestyles were essentially sedentary. More recent well-designed studies that have employed either the classic nitrogen balance approach or the more technically difficult metabolic tracer technique indicate that overall protein needs (as well as needs for some specific individual amino acids) are probably increased for those who exercise regularly.
Although the roles of the additionally required dietary protein and amino acids are likely to be quite different for those who engage in endurance exercise (protein required as an auxiliary fuel source) as opposed to strength exercise (amino acids required as building blocks for muscle development), it appears that both groups likely will benefit from diets containing more protein.
The current international RDA of 0.8g per kg of body weight per day.
Strength athletes need about 1.4-1.8g per kg of body weight per day.
Endurance athletes need about 1.2-1.4g per kg of body weight per day.
Effect of branched-Chain Amino Acid Supplementation on Muscle Soreness following Exercise: A Meta-Analysis.
International Journal for Vitamin and Nutrition Research, FEDEWA, M.V., et al. (2019).
The primary aim of this study was to examine the previous literature assessing the effect of BCAA supplementation on delayed onset muscle soreness (DOMS) following an acute bout of exercise in adults.
The cumulative results of 37 effects gathered from 8 studies published between 2007 and 2017 indicated that BCAA supplementation reduced DOMS following exercise training. A large decrease in DOMS occurs following BCAA supplementation after exercise compared to a placebo supplement.
An oral essential amino acid-carbohydrate supplement enhances muscle protein anabolism after resistance exercise.
Journal of Applied Physiology, RASMUSSEN, B., et al. (2000).
This study was designed to determine the response of muscle protein to the bolus ingestion of a drink containing essential amino acids and carbohydrate after resistance exercise. Six subjects (3 men, 3 women) randomly consumed a treatment drink (6 g essential amino acids, 35 g sucrose) or a flavoured placebo drink 1 h or 3 h after a bout of resistance exercise on two separate occasions.
We conclude that essential amino acids with carbohydrates stimulate muscle protein anabolism by increasing muscle protein synthesis when ingested 1 or 3 h after resistance exercise.
To be healthier
You're an active person interested in using amino acids to support your general health.
Reduce muscle loss as you age
Muscle loss, or sarcopenia, is a natural part of ageing. After age 30, you begin to lose around 3% to 5% per decade even if you’re active. Leucine-enriched amino acids can reverse the natural muscle loss that occurs with ageing.
Delay the onset of fatigue
Studies show that increased serotonin levels during exercise play a role in fighting fatigue. Consuming amino acids (particularly BCAAs) during workouts can further delay the onset of fatigue.
EAAs are less inflammatory than other amino acid options. It’s a great choice for ageing populations or those with inflammatory disorders.
Easy on digestion
EAAs are rapidly absorbed compared to other proteins. This makes them particularly suitable for ageing populations and digestive disorders.
Essential amino acids are primarily responsible for the amino acid stimulation of muscle protein anabolism in healthy elderly adults.
The American Journal of Clinical Nutrition, VOLPI, E., et al. (2003).
To assess whether non-essential amino acids are required in a nutritional supplement to stimulate muscle protein anabolism in the elderly.
Essential amino acids (EAAs) are primarily responsible for the amino acid-induced stimulation of muscle protein anabolism in the elderly.
Anti-inflammatory and analgesic properties of four amino-acids.
Indian Journal of Physiology and Pharmacology, SAXENA, R.N., et al. (1984).
Orally administered L-isoleucine, DL-isoleucine and L-leucine exhibited anti-inflammatory activity in many test models of inflammation except formaldehyde-induced inflammation. The amino-acids produced no gastric ulceration or overt acute toxicity in doses which effectively suppress inflammation.
Amino acid supplements and metabolic health: a potential interplay between intestinal microbiota and systems control.
Genes and Nutrition, BIFARI, F., et al. (2017).
A review of the accumulating body of knowledge on the impact of dietary EAA supplementation on the host metabolic health and health-span from a holistic perspective. Moreover, we will focus on the current efforts to establish causal relationships among dietary EAAs, gut microbiota, and health during human development.
The hypothesis is that specific amino acid mixtures are likely to be of benefit to people who follow a typical Western-style diet, in addition to dietary fiber and prebiotics. A deeper understanding of the efficacy of such dietary supplements to maintain gut microbiota has the potential to contribute important therapeutic tools in human metabolic health and weight control.
Meet the amino acids
9 ESSENTIAL AMINO ACIDS
The body cannot produce these amino acids and we have to consume them through our diet and supplementation.
This branched-chain amino acid triggers protein synthesis and the renewal of muscle cells. It is also involved in the maintenance of mental performance during prolonged physical efforts.
It is also known that leucine is transformed into a substance known as acetyl coenzyme A. This plays an important role in the breakdown of carbohydrates and fatty acids. As a result, leucine plays a crucial part in breaking food down into energy.
This branched-chain amino acid is involved in the maintenance of intellectual performance during prolonged physical efforts. It also promotes protein synthesis in muscle after exercise.
Not only that, but valine is a major element in haemoglobin molecules and is also closely associated with the body's response to insulin.
Isoleucine is a branched-chain amino acid involved in the maintenance of mental performance during intense, prolonged exercises. It also supports muscle protein synthesis after workouts.
Isoleucine is intimately involved in the formation of red blood cells, and the control of blood sugar in response to food.
As a precursor to carnitine, lysine stimulates the production of growth hormones. Lysine and vitamin D are also responsible for the absorption of calcium from our diets, helping to support strong bones and teeth.
Studies also suggest that lysine can affect our behaviour. Research shows a clinically significant reduction in feelings of anxiety – and in the levels of hormones associated with stress – when lysine is at healthy levels.
This amino acid is a precursor of serotonin, melatonin and vitamin B3. The distribution in the central nervous system improves when circulating BCAA levels are lowered after physical exercise.
Like lysine, there is mounting evidence to suggest that tryptophan affects behaviour. It is known that tryptophan is converted into a substance known as 5-HTP, which is a precursor of the neurotransmitter serotonin. Increasing serotonin results in the induction of sleep and reduces appetite.
Tryptophan is also used in the creation of melatonin, often known as the “sleep hormone”; studies show it can result in longer sleep duration. Studies of children suffering from night terrors also showed that tryptophan supplements had a positive impact.
Tryptophan can also influence neurotransmission within the brain, which may have an impact on depression. One study found that bipolar patients who supplement with this amino acid experience fewer relapses in their condition, while another study, where women were deliberately fed a tryptophan-deficient diet, experienced a clinically relevant increase in depressive symptoms.
Finally, studies have suggested that low-calorie diets may reduce tryptophan levels in the body. It has been proposed that this may explain some of the difficulties experienced when trying to lose weight.
This sulphur-containing amino acid possesses antioxidant properties. It is also a precursor to creatine, carnitine, and S-adenosylmethionine (SAM) and studies suggest that methionine is involved in the development of muscle.
Scientists have also demonstrated that methionine plays a crucial role in the growth of blood vessels and that a deficiency can lead to greying hair.
It also seems to have a beneficial impact on helping the body deal with toxins. A methionine supplement has been used successfully to reverse the negative impacts of copper poisoning and issues associated with an overdose of paracetamol.
This precursor to tyrosine also plays a role in feeling full and in muscle development.
Phenylalanine is sometimes referred to as the “feel-good amino acid” because it is converted into molecules that transmit positive messages around the body. These molecules include adrenaline, noradrenaline and dopamine, which is the neurotransmitter that activates the pleasure centre of the brain.
Interestingly, a lack of these neurotransmitters is associated with a range of health conditions including ADHD, restless leg syndrome, schizophrenia and Parkinson's disease.
This amino acid is indispensable because the body cannot produce it.
Threonine is known to play a structural role in connective tissue. It is also a precursor to two molecules responsible for the transmission of nerve impulses around the body. Threonine can be converted in the body into a substance known as “glycine”, which blocks the transmission of nerve impulses, meaning it can be beneficial for conditions associated with muscle spasms.
However, it can also be turned into serine, which has the opposite effect. Getting enough threonine gives your body the ability to regulate these nervous transmissions.
Abundant in hemoglobin, it promotes the production of red blood cells. It also favours copper assimilation, and as a precursor of glutamate, it provides a source of muscular energy.
As its name suggests, histidine is a precursor to histamine. Anyone suffering from hay fever or other allergies may have found themselves being prescribed with antihistamines, because it is histamine that helps to trigger an inflammatory response.
While this substance may prove frustrating for some individuals in pollen season, it is also a crucial part of the immune system, ensuring the white blood cells are capable of dealing with infection.
Evidence also suggests that histidine plays a role in the healthy creation of red blood cells. These red blood cells, in turn, carry nutrients around the body, ensuring that your cells have the resources they need to function efficiently.
In experiments where histidine deficiency has been studied, participants are found to rapidly lose weight and develop skin lesions. When the deficiency was removed, these unfortunate symptoms rapidly also cleared up.
*Branched-chain amino acids (BCAAs) - because they’re the only amino acids that have a chain that branches to the side. Alongside the other essential amino acids, BCAAs are important for energy and muscle metabolism.
11 NON-ESSENTIAL amino acids
These can be produced by our bodies.
A conditionally essential amino acid**, it is the most abundant found in muscles. It is a source of energy recruited for the Krebs cycle. As a precursor of ornithine and citrulline, it plays an important role in metabolic detoxification of urea. Glutamate is a neurotransmitter and precursor of gamma- aminobutyric acid (GABA). This amino acid plays a vital role in supplying energy to immune cells and also promotes the maintenance of the body’s natural defenses when subjected to intense physical activity. Lastly, it is a component of glutathione (antioxidant activity).
A conditionally essential amino acid**, it is precursor for the synthesis of other amino acids and creatine. It participates in the synthesis of nitrogen monoxide (NO), an important part of blood pressure regulation. It plays an important role in eliminating (detoxifying) ammonia from the body. Furthermore, it stimulates secretion functions of the pancreas and also contributes to the regulation of insulin production. Lastly, it promotes the release of the growth hormone (GH).
Involved with memory, mental fatigue, and participates in the protection against free radicals produced by glutathione, an important controlling element of excess free radicals (antioxidant activity).
A conditionally essential amino acid**, it is a precursor for catecholamine (adrenaline), melanin (skin pigmentation), and thyroxine (thyroid hormone). Associated with a high-protein diet, it can favor weight loss. It also has a positive effect on balancing the nervous system and particularly stress management.
A conditionally essential** sulfur-containing amino acid, it represents an important part of amino acids present in skin, hair, and nails. Cystine is the stable form of cysteine.
It is the most important amino acid released in large quantities by muscles during muscle breakdown. It participates in the restoration of energy reserves by promoting gluconeogenesis.
This amino acid is dependent on aspartic acid. It is one of the precursors of DNA and RNA synthesis which constitutes the
A conditionally essential amino acid**, it is a substrate for the synthesis of creatine. It is also one of the precursors of DNA and RNA synthesis, the « genetic blueprint » of our cells. Lastly, it is a component of glutathione, an important part of controlling excess free radicals (antioxidant activity).
A conditionally essential amino acid**, it is necessary for the stability of the collagen triple helix. Thus, it is present in increase quantities in the skin, and also in cartilage and bone. It is therefore abundantly present in the skin, as well as in cartilage and bone.
Amino acid involved in the biosynthesis of cysteine and phospholipids of the brain, necessary for cognitive functions.
Essential to detoxification processes, it also acts as a neurotransmitter. It participates in the synthesis of ATP, the energy source to all cells.
**Conditionally essential amino acid - these are sometimes "essential", in times of illness and stress.