What are dietary proteins and amino acids?

Proteins play a vital role in human metabolism and overall health. Protein is essential for the growth, maintenance, and repair of the body's tissues, including muscles, bones, skin, hair, and nails. Proteins are made up of smaller units called amino acids, the building blocks of proteins.

Some of the key roles of proteins in metabolic health and performance include:

1. Muscle growth and repair: Proteins are necessary for muscle growth and repair, which is essential for maintaining muscle mass and strength, which in turn is important for overall metabolic health and physical performance.
2. Enzyme and Hormone function: Proteins also play a key role in enzyme and hormone function, which are essential for metabolic reactions and regulation. Enzymes are required for almost all the chemical reactions that occur in the body, and hormones regulate many bodily functions, including metabolism.
3. Energy production: Proteins can also be used as an energy source, particularly during periods of low glucose availability, such as during exercise or in individuals with diabetes.
4. Metabolic rate: Adequate intake of proteins can increase the body's metabolic rate, which can help to burn calories and promote weight loss.
5. Satiety: Proteins can also promote feelings of fullness and satisfaction, which can help to reduce food cravings and manage weight.
6. Immune function: Proteins are also important for the function of the immune system, which is important for maintaining overall health and preventing infections.
7. Maintaining muscle mass: Adequate intake of protein, especially essential amino acids, is crucial for maintaining muscle mass and function, especially for athletes and older adults, who are at risk

Who discovered protein?

The discovery of protein can be traced back to the early 19th century. In 1838, a German scientist named Justus von Liebig discovered that a substance he called "albuminoids" was present in all living organisms. He was the first to isolate and purify a protein, which he named "albumin", from egg white.

In 1839, a Dutch chemist named Gerrit Jan Mulder discovered a substance he called "proteins" in a wide variety of animal and plant tissues. He identified it as a distinct class of biomolecules and separated it from carbohydrates and lipids.

In 1845, a Danish biochemist named Wilhelm Kühne coined the term "protein" (from the Greek proteios, meaning "primary" or "taking the first place") to describe the class of biomolecules discovered by Mulder.

It is important to note that many scientists have contributed to the field of protein research. Many more discoveries and insights have been made since the initial discoveries of Justus von Liebig, Gerrit Jan Mulder, and Wilhelm Kühne.

The knowledge of protein structure, function, and metabolism has greatly expanded and deepened over the years, contributing to the current understanding of the role of protein in human health and nutrition.

What types of Proteins are in the human body?

Many different types of proteins are found in nature, each with unique properties and functions. Some of the main types of proteins include:

1. Structural proteins: These proteins provide structure and support to the body's cells and tissues. Examples of structural proteins include collagen, which is found in skin, tendons, and bones, and keratin, which is found in hair and nails.
2. Transport proteins: These proteins transport molecules and ions around the body. Examples of transport proteins include haemoglobin, which carries oxygen in the blood, and ceruloplasmin, which carries copper in the blood.
3. Enzymes: These proteins catalyse chemical reactions in the body. Examples of enzymes include lactase, which breaks down lactose in milk, and pepsin, which breaks down proteins in food.
4. Hormones: These proteins act as chemical messengers that help to regulate metabolism and other bodily functions. Examples of hormones include insulin, which regulates blood sugar levels, and thyroid-stimulating hormone, which regulates metabolism.
5. Antibodies: These proteins help to protect the body against foreign invaders such as viruses and bacteria. Antibodies are also known as immunoglobulins; they recognise and bind to specific pathogens.
6. Contractile proteins: These are proteins that are responsible for the movement of the body. Actin and myosin are examples of contractile proteins that are responsible for muscle contraction.
7. Storage proteins: These proteins store essential nutrients, such as iron, zinc, and copper. Examples of storage proteins include ferritin, which stores iron, and ceruloplasmin, which stores copper.

Proteins are composed of chains of amino acids. Different properties of the proteins are related to the unique sequence of the amino acids. Proteins are essential for health and well-being. A balanced diet that includes a variety of protein sources can help ensure adequate intake of all the essential amino acids.

Who discovered amino acids?

Amino acids, the building blocks of proteins, were first discovered in the early 19th century. In 1806, French chemist Francois-Pierre-Joseph René Bretonneau was the first to identify and name an amino acid, aspartic acid, from asparagus juice. In 1819, Swedish chemist Jöns Jakob Berzelius discovered a second amino acid, cystine, while working with cysteine-rich animal matter.

In 1820, German chemist Friedrich Wöhler further established the nature of amino acids by synthesizing the first non-natural amino acid, glycine, from a related compound, glycolic acid. This synthesis marked the first time an organic compound was synthesized from inorganic materials. It led Wöhler to conclude that organic compounds could be made from inorganic compounds, which challenged the prevailing view of the time that organic compounds could only be made from living organisms.

In the following decades, many more amino acids were discovered and characterized by various scientists, including William Prout, who proposed in 1849 that proteins were composed of combinations of amino acids, and Emil Fischer, who, in 1902, discovered and characterized many of the amino acids that make up proteins.

The word "amino acids" was first coined in 1838 by German chemist Wilhelm Heinrich Kuhne, who used the term to refer to a class of compounds that includes both natural and artificial substances.

What are Essential Amino Acids and Non-Essential Amino Acids?

Amino acids are the building blocks of proteins. There are 20 different types of amino acids, and they are categorized as either essential or non-essential.

Essential amino acids:

These are the amino acids that the body cannot produce on its own and must be obtained through the diet. They are essential for many functions such as muscle growth, enzyme production, and hormone regulation. There are 9 essential amino acids:

• Histidine
• Isoleucine
• Leucine
• Lysine
• Methionine
• Phenylalanine
• Threonine
• Tryptophan
• Valine

Non-essential amino acids:

These are the amino acids that the body can produce on its own and do not need to be obtained through the diet. There are 11 non-essential amino acids:

• Alanine
• Asparagine
• Aspartic acid
• Cysteine
• Glutamine
• Glutamic acid
• Glycine
• Proline
• Serine
• Tyrosine

It's worth noting that some non-essential amino acids can become conditionally essential, which means that the body may not produce enough of them in certain conditions. For example, glutamine is non-essential but can become conditionally essential during periods of stress, such as injury or disease, as the body's demand for glutamine increases.

In summary, Essential amino acids are the amino acids that the body cannot produce on its own and must be obtained through the diet, while non-essential amino acids are the amino acids that the body can produce on its own and do not need to be obtained through the diet. However, some non-essential amino acids can become conditionally essential in certain conditions.

How does nutritional science measure protein quality?

Nutritional science uses a variety of methods to measure the quality of proteins. The most commonly used methods include:

1. Protein Efficiency Ratio (PER): The Protein Efficiency Ratio (PER) is a measure of the growth-promoting ability of a protein. It is determined by measuring the weight gain of a test animal (typically rats) that is fed a diet containing a specific protein source over a period of time. The ratio of weight gain to protein intake is calculated and used as a measure of protein quality.
2. Biological Value (BV): The Biological Value (BV) is a measure of the proportion of absorbed protein that is retained and used for growth and maintenance in the body. It is calculated by dividing the amount of nitrogen retained in the body by the amount of nitrogen absorbed from the diet.
3. Net Protein Utilization (NPU): The Net Protein Utilization (NPU) is a measure of the efficiency of protein utilization by the body. It is calculated by dividing the amount of nitrogen retained in the body by the amount of nitrogen absorbed from the diet.
4. Protein Digestibility Corrected Amino Acid Score (PDCAAS): The PDCAAS is a method of evaluating protein quality based on both the amino acid requirements of humans and their ability to digest the protein. It compares the amino acid composition of a protein to the reference pattern for human amino acid requirements, and then assigns a score based on the highest scoring amino acid.
5. Digestible Indispensable Amino Acid Score (DIAAS): The DIAAS is a similar method to PDCAAS, but it takes into account the digestibility of the protein. It compares the amino acid composition of a protein to the reference pattern for human amino acid requirements, after correcting for digestibility and assigns a score based on the highest scoring amino acid.

Each of these methods has its own strengths and weaknesses and should be used in the context of the specific research question and population. The PDCAAS and DIAAS are more widely used and recognized by international organizations such as the WHO and FAO as the preferred method for evaluating protein quality in food and supplements.

What is DIAAS?

Who invented DIAAS?

The Digestible Indispensable Amino Acid Score (DIAAS) was developed by the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) in 2013.

The development of DIAAS was led by a group of international experts in the field of nutrition and amino acids metabolism. The method was created to improve upon the Protein Digestibility Corrected Amino Acid Score (PDCAAS), which was the previously recognized method for evaluating protein quality by WHO and FAO.

The DIAAS method was developed to take into account the digestibility of the protein in addition to its amino acid content and was adopted as the preferred method for evaluating protein quality in food and supplements by the WHO and FAO.

Calculating DIAAS

The Digestible Indispensable Amino Acid Score (DIAAS) is a method used to evaluate the quality of proteins based on their amino acid content and digestibility. The formula for calculating DIAAS is as follows:

DIAAS = (mg/g of digestible indispensable amino acids in the test protein/mg/g of the same amino acids in the reference pattern) x 100

The reference pattern used in the calculation is typically the pattern of amino acid requirements for humans established by the World Health Organization (WHO) or the Food and Agriculture Organization (FAO). The reference pattern is based on the daily requirements for each indispensable amino acid per kilogram of body weight for different age and gender groups.

The digestibility of the protein is also considered in the DIAAS calculation. This is typically determined by measuring the proportion of the protein absorbed by the body after it is consumed. It can be done in different ways, such as by measuring the body's nitrogen balance or using isotope tracer methods.

DIAAS is considered a more accurate method of evaluating protein quality than Protein Digestibility Corrected Amino Acid Score (PDCAAS) as it considers both the amino acid content and digestibility of the protein.

What is blood nitrogen balance and why is it important?

Blood nitrogen balance refers to the balance between the amount of nitrogen that enters the body through dietary protein and the amount of nitrogen that leaves the body through the loss of protein in urine, faeces, and sweat. The balance can be positive, negative, or neutral.

Positive nitrogen balance

When the body is in a positive nitrogen balance, more nitrogen is entering the body than leaving it. Positive nitrogen balance is typically seen during growth periods, such as during childhood or pregnancy, or when the body is recovering from injury or illness.

Negative nitrogen balance

When the body is in a negative nitrogen balance, more nitrogen is leaving the body than entering it. This can occur when the body is under stress, such as during starvation, illness, or injury, and can lead to muscle wasting and weakness.

Neutral nitrogen balance

When the body is in a neutral nitrogen balance, the amount of nitrogen entering the body equals the amount leaving it. This is considered a healthy state and is typically seen in adults who are maintaining their body weight and muscle mass.

Measuring nitrogen balance can be used to evaluate a person's protein needs and to assess the effectiveness of a dietary or medical intervention. When a person is in a positive nitrogen balance, it means that they are in a state of growth or recovery. When a person is in negative nitrogen balance, it means that the body is breaking down proteins.

What are the benefits of a positive blood nitrogen balance for metabolic health and performance?

Positive nitrogen balance can have several benefits for metabolic performance, including:

1. Muscle growth and recovery: Positive nitrogen balance is necessary for muscle growth and recovery. It allows the body to repair and build new muscle fibres, which can improve muscle strength and endurance.
2. Blood sugar regulation: Adequate protein intake is necessary to support healthy blood sugar levels. Protein can help slow the absorption of carbohydrates and keep blood sugar levels stable, which can benefit individuals with diabetes or metabolic disorders.
3. Hormone regulation: Many hormones in the body, such as insulin, are made from proteins. Consuming adequate amounts of protein can help to regulate the production and balance of these hormones, which is important for overall health.
4. Immune system function: Protein is important for the production of antibodies and other immune cells, which help to protect the body against infection and disease.
5. Enzyme production: Many enzymes that catalyse metabolic reactions in the body are made from proteins. Consuming adequate amounts of protein can help support these enzymes' production, which is important for overall metabolism.
6. Weight management: Positive nitrogen balance can help to maintain muscle mass and strength, which can aid in weight management.

It's important to note that even though a positive nitrogen balance is beneficial for overall health and performance, excess protein intake may have adverse effects on the body. Therefore, consuming adequate but not excessive amounts of protein is important to maintain optimal health and performance.

How much is science still learning about protein intake and metabolism?

Science is still learning a lot about the effects of protein intake on metabolism. While researchers have a general understanding, there are still many unanswered questions and ongoing research in this areas and many more:

1. Optimal Protein intake: There is an ongoing debate about the optimal amount of protein that should be consumed for optimal health and performance. The current recommended daily intake for protein varies depending on factors such as age, sex, and activity level. However, it's still not clear if these guidelines are accurate for everyone.
2. Protein Quality: Different sources of protein have different amino acid profiles and digestibility, and different sources of protein may have different effects on health and performance. Research is ongoing to determine the optimal protein sources for different populations and health conditions.
3. Protein Timing: Research is ongoing to determine the optimal timing of protein consumption for muscle growth and recovery. Studies have shown that consuming protein soon after exercise may be beneficial. However, it's still unclear if this is the case for everyone.
4. Protein and chronic diseases: There is ongoing research on the role of protein intake in the development and management of chronic diseases such as obesity, diabetes, and cardiovascular disease. Studies have shown that consuming adequate amounts of protein can be beneficial for these conditions, but it's still not clear if certain sources of protein or patterns of consumption are more beneficial than others.
5. Personalized Nutrition: With the increasing knowledge of the gut microbiome and the role of genetics, researchers are starting to understand that protein requirements may vary from person to person and that a one-size-fits-all approach may not be the best for optimal health.

Overall, the field of protein research is rapidly evolving, and new findings are being published regularly. As more research is conducted, scientists will continue to gain a deeper understanding of the effects of protein intake on metabolism.

What are the roles of each Amino Acid in metabolic health and performance?

Essential amino acids:

These are the amino acids that the body cannot produce on its own and must be obtained through the diet. They are essential for many functions such as muscle growth, enzyme production, and hormone regulation. There are 9 essential amino acids:

Histidine

Histidine is an essential amino acid, which means that it is a building block of proteins and cannot be produced by the body. It must be obtained through diet.

Histidine’s role in metabolism

Histidine plays a vital role in several metabolic pathways that are critical for overall health and well-being.

One of the main roles of Histidine in metabolism is in the formation of histamine, a compound that is involved in various biological processes such as immune response, digestion, and regulation of blood flow. Histamine is also an important neurotransmitter which is involved in the regulation of mood and appetite.

Histidine also acts as a metal-binding agent, which means that it helps to transport metal ions such as zinc and copper throughout the body, and it plays a role in the formation of hemoglobin and myoglobin, which are the proteins that transport oxygen in the blood.

Histidine is also involved in the regulation of pH levels in the body, and it plays a role in the formation of red blood cells and the repair of tissues.

In addition, Histidine is also involved in the production of carnosine, which is a dipeptide composed of Histidine and beta-alanine, it is found in high concentrations in muscle and brain tissue. Carnosine has antioxidant properties and can help protect cells from damage by free radicals.

Additional functions of histidine in the body include:

• Haemoglobin synthesis: Histidine is a precursor for the production of haemoglobin, the protein in red blood cells that carries oxygen to the body's tissues.
• Myelin formation: Histidine is also important for the formation of myelin, the protective coating that surrounds nerve cells, and therefore, it is important for the nervous system to function well.
• Antioxidant activity: Histidine is a precursor to the antioxidant enzyme histidine dipeptides, which help to protect cells from damage caused by free radicals.
• Hormone regulation: Histidine has been found to play a role in the regulation of growth hormone and melatonin, the hormone that helps to regulate sleep and wake cycles.
• Metabolic reactions: Histidine also plays a role in various metabolic reactions, such as the metabolism of histamine and the metabolism of purines.
• Histamine synthesis: Histidine is a precursor of histamine, a neurotransmitter that plays a role in immune responses, neurotransmission and the regulation of gut functions.
• Histidine is an essential amino acid that is important for many bodily functions, such as oxygen transport, nervous system function, antioxidant defence, hormone regulation, and histamine synthesis. Adequate intake of histidine are important for maintaining good health and preventing deficiencies.

In summary, Histidine plays a vital role in several metabolic pathways that are critical for overall health, including the formation of histamine, as a metal-binding agent, in the formation of haemoglobin and myoglobin, pH regulation, red blood cells formation and tissue repair, and the production of carnosine.

Adequate intake of histidine is important for maintaining good health and preventing deficiencies.

Isoleucine

Isoleucine is an essential amino acid, which means that it is a building block of proteins and cannot be produced by the body. It must be obtained through diet. Isoleucine is one of the three branched-chain amino acids (BCAAs) along with leucine and valine.

Isoleucine’s role in metabolism

Isoleucine plays a critical role in several metabolic pathways, including muscle protein synthesis, glucose metabolism, and energy metabolism.

In muscle protein synthesis, Isoleucine, along with leucine and valine, helps to maintain and repair muscle tissue by providing the necessary building blocks for muscle growth and recovery. This is important for maintaining and building muscle mass, which is crucial for overall health and physical performance.

In glucose metabolism, Isoleucine helps to regulate blood sugar levels by stimulating insulin secretion and improving insulin sensitivity. This can help to reduce the risk of type 2 diabetes and other metabolic disorders by preventing high blood sugar levels and improving the body's ability to use insulin effectively.

Isoleucine also plays a role in energy metabolism by providing energy for the body, especially during periods of intense physical activity. It can also be used as a source of energy by the brain and central nervous system, making it crucial for maintaining cognitive and neurological function.

In addition, Isoleucine also has an effect on the metabolism of haemoglobin synthesis by helping the formation of red blood cells, which are crucial for oxygen transportation throughout the body.

Additional functions of Isoleucine in the body include:

• Energy production: Isoleucine plays a role in the production of glucose, which is an important source of energy for the body. It also is involved in regulating blood sugar levels which can help maintain energy levels.
• Muscle and tissue repair: Isoleucine is needed for the repair and growth of muscle and other tissues. It also plays a role in wound healing and in the formation of red blood cells.
• Hormone regulation: Isoleucine is involved in the synthesis of several hormones, including insulin, a hormone that regulates blood sugar levels, and growth hormone, which is important for muscle growth and tissue repair.
• Immune function: Isoleucine is important for the immune system, by promoting the growth and repair of white blood cells, which helps to fight off infections and illnesses.
• Transport of molecules and ions: Isoleucine is involved in the transport of molecules and ions, such as potassium and sodium, which are important for maintaining proper fluid balance in the body.
• Endurance exercise: Isoleucine can help promote endurance and recovery during exercise, and it can help reduce muscle damage and fatigue, promoting muscle protein synthesis and repairing muscle tissue.

In summary, Isoleucine is an essential amino acid that plays a number of important roles in human metabolic health and performance. It plays a role in energy production, muscle and tissue repair, hormone regulation, immune function, transport of molecules and ions and endurance exercise.

Adequate intake of isoleucine is important for maintaining good health and preventing deficiencies.

Leucine

Leucine is an essential amino acid, which means that it is a building block of proteins and cannot be produced by the body. It must be obtained through diet. Leucine is one of the three branched-chain amino acids (BCAA), along with isoleucine and valine.

Leucine’s role in metabolism

Leucine plays a critical role in the regulation of metabolism by promoting muscle growth and repair, regulating blood sugar levels, and increasing energy expenditure and fat burning.

In muscle protein synthesis, Leucine acts as a key regulator, stimulating muscle protein synthesis and helping to preserve muscle mass during periods of calorie restriction or inactivity. This makes it an essential nutrient for muscle growth and repair, especially for athletes.

In glucose metabolism, Leucine helps to regulate blood sugar levels by stimulating insulin secretion and improving insulin sensitivity. This can help to reduce the risk of type 2 diabetes and other metabolic disorders.

Leucine also has an effect on the metabolic rate, as it helps to increase energy expenditure and fat burning. This can be beneficial for weight loss and body composition, as it can help to burn more calories and reduce fat storage.

Furthermore, Leucine also plays a role in regulating appetite and energy homeostasis by stimulating the release of gut hormones and neurotransmitters that regulate food intake.

Additional functions of leucine in the body include:

• Protein synthesis: Leucine is considered the main trigger of muscle protein synthesis, which is essential for muscle growth and repair. It plays a crucial role in muscle protein synthesis by activating mTOR, a key signalling protein that regulates protein synthesis.
• Glucose metabolism: Leucine plays a role in glucose metabolism by regulating the levels of blood sugar, it can also have a role in preventing muscle loss and promoting muscle gain during weight loss.
• Hormone regulation: Leucine is involved in the regulation of growth hormone and insulin, two hormones that play a crucial role in muscle growth and glucose metabolism.
• Energy production: Leucine is involved in the production of energy-rich molecules such as ATP, which is important for energy metabolism and physical performance.
• Appetite control: Leucine has been found to have an effect on appetite control, by promoting feelings of fullness, and reduces the risk of overeating.
• Wound healing: Leucine plays a role in wound healing and tissue repair, by promoting cell growth and regeneration.

In summary, Leucine is an essential amino acid that plays an important role in human metabolic health and performance by regulating muscle protein synthesis, glucose metabolism, hormone regulation, energy production, appetite control and wound healing.

Adequate intake of Leucine is important for maintaining good health and preventing deficiencies. It is particularly important for athletes and bodybuilders as it is necessary for muscle growth and recovery.

Lysine

Lysine is an essential amino acid, which means that it is a building block of proteins and cannot be produced by the body. It must be obtained through diet.

Lysine’s role in metabolism

Lysine plays a vital role in several metabolic pathways that are critical for overall health and well-being.

One of the main roles of Lysine in metabolism is in collagen synthesis, which is necessary for the formation of skin, bones, and connective tissue. Collagen is the main protein found in connective tissue and makes up about 30% of the total protein in the human body. Lysine is one of the three essential amino acids that are necessary for collagen synthesis.

Lysine also plays a role in the absorption of calcium, which is essential for maintaining healthy bones and teeth. Lysine helps in the formation of bones by promoting the absorption and retention of calcium, making it a vital nutrient for bone health.

Lysine also plays a role in the production of carnitine, a molecule that helps the body to convert fat into energy. This can be beneficial for weight loss and body composition.

In addition to these, Lysine is also involved in the production of antibodies, enzymes, and hormones, and it also helps in the absorption of iron.

Additional functions of lysine in the body include:

• Protein synthesis: Lysine is an essential component of many proteins in the body, it is required for the production of collagen, which is an important protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Calcium absorption: Lysine plays a role in the absorption of calcium, which is important for maintaining strong bones and teeth.
• Hormone regulation: Lysine is involved in the production of carnitine, a compound that helps to transport fat to the mitochondria for energy production, and also plays a role in the production of enzymes that are important for hormone metabolism.
• Antiviral properties: Lysine has been found to have antiviral properties, which can help to prevent or reduce the severity of viral infections, such as herpes simplex virus (HSV).
• Immune function: Lysine plays a role in maintaining the integrity of the immune system, by helping to form antibodies and supporting the production of white blood cells, which help to fight off infections and illnesses.
• Appetite control: Lysine has been found to have an effect on appetite control, by promoting feelings of fullness and reduce the risk of overeating.

In summary, Lysine is an essential amino acid that plays an important role in human metabolic health and performance by being involved in protein synthesis, calcium absorption, hormone regulation, antiviral properties, immune function and appetite control.

Adequate intake of lysine is important for maintaining good health and preventing deficiencies. It's particularly important for people with a diet that is deficient in lysine, athletes and people recovering from injuries, as they require extra lysine for growth and repair.

Methionine

Methionine is an essential amino acid, which means that it is a building block of proteins and cannot be produced by the body. It must be obtained through diet.

Methionine’s role in metabolism

Methionine plays a vital role in several metabolic pathways that are critical for overall health and well-being.

One of the main roles of Methionine in metabolism is in the formation of S-adenosylmethionine (SAMe), a compound that is involved in various biological processes such as methylation, regulation of gene expression, and the synthesis of neurotransmitters. SAMe is a key methyl donor in the body and helps to regulate gene expression and the production of hormones, neurotransmitters and other important molecules in the body.

Methionine also acts as a methyl donor, which means that it donates methyl groups to other molecules in the body. This process is important for the regulation of gene expression, the formation of certain hormones, and the detoxification of harmful substances.

Methionine also plays a role in the production of cysteine, which is another essential amino acid that is involved in the formation of the antioxidant glutathione and the formation of hair and nails.

In addition, Methionine is also involved in the production of taurine and phosphatidylcholine, which are important for the proper functioning of the liver and cardiovascular system.

Additional functions of methionine in the body include:

• Protein synthesis: Methionine is an essential component of many proteins in the body, it is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Antioxidant activity: Methionine is a precursor for the production of the antioxidant enzyme glutathione, which helps to protect cells from damage caused by free radicals.
• Detoxification: Methionine helps to remove heavy metals and other toxins from the body by acting as a methyl donor in the process of methylation, this is important for the overall detoxification of the body.
• Methylation: Methionine is also a methyl donor, which means that it can donate a methyl group to other molecules, this process is important for the regulation of gene expression, the production of hormones and neurotransmitters.
• Lipid metabolism: Methionine plays a role in the metabolism of lipids, by helping to lower cholesterol levels and reduce the risk of heart disease.
• Energy production: Methionine is involved in the production of energy-rich molecules such as S-Adenosylmethionine (SAMe), which is important for energy metabolism and physical performance.

In summary, Methionine is an essential amino acid that plays an important role in human metabolic health and performance by being involved in protein synthesis, antioxidant activity, detoxification, methylation, lipid metabolism, and energy production.

Adequate intake of methionine is important for maintaining good health and preventing deficiencies. It's also important for athletes, people recovering from injuries and people with certain conditions such as liver disease, as they may require extra methionine for growth and repair, and to support the detoxification process.

Phenylalanine

Phenylalanine is an essential amino acid, which means that it is a building block of proteins and cannot be produced by the body. It must be obtained through diet.

Phenylalanine’s role in metabolism

Phenylalanine plays a vital role in several metabolic pathways that are critical for overall health and well-being.

One of the main roles of Phenylalanine in metabolism is in the synthesis of the important neurotransmitters dopamine, norepinephrine, and epinephrine, which are involved in mood regulation, motivation, and attention. Phenylalanine is converted into tyrosine by the enzyme phenylalanine hydroxylase, and tyrosine is then converted into the neurotransmitters.

Phenylalanine also plays a role in the formation of melanin, the pigment that gives colour to the skin, hair, and eyes. Melanin is synthesized from tyrosine, which is a derivative of Phenylalanine.

Phenylalanine is also involved in the regulation of appetite and energy metabolism. It plays a role in the production of the hormone cholecystokinin (CCK), which is involved in the regulation of food intake and digestion.

In addition, Phenylalanine is also involved in the production of thyroxine, a hormone involved in the regulation of metabolism.

Additional functions of phenylalanine in the body include:

• Protein synthesis: Phenylalanine is an essential component of many proteins in the body, it is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Neurotransmitter synthesis: Phenylalanine is a precursor for the production of the neurotransmitters dopamine, norepinephrine and epinephrine, which are important for the regulation of mood, attention, and movement.
• Melanin production: Phenylalanine is involved in the production of the pigment melanin, which gives colour to the skin, hair, and eyes.
• Appetite control: Phenylalanine has been found to have an effect on appetite control, by promoting feelings of fullness and reduce the risk of overeating.
• Fatigue reduction: Phenylalanine can help to reduce feelings of fatigue and increase energy levels, this can be helpful for those with chronic fatigue syndrome.
• Pain relief: Phenylalanine can be converted into another amino acid tyrosine, which can help to produce endorphins, natural painkillers, which can help to relieve pain caused by different conditions such as menstrual cramps, headaches and other types of pain.

In summary, Phenylalanine plays a vital role in several metabolic pathways that are critical for overall health, including the synthesis of neurotransmitters, formation of melanin, regulation of appetite and energy metabolism and production of cholecystokinin and thyroxine.

Adequate intake of phenylalanine is important for maintaining good health and preventing deficiencies. It's also important for people with conditions such as phenylketonuria, as they need to avoid high levels of phenylalanine in their diet.

Threonine

Threonine is an essential amino acid, which means that it is a building block of proteins and cannot be produced by the body. It must be obtained through diet.

Threonine’s role in metabolism

Threonine plays a vital role in several metabolic pathways that are critical for overall health and well-being.

One of Threonine's main roles in metabolism is the formation of collagen and elastin, which are the proteins that provide structure and elasticity to the skin, bones, and other tissues. Threonine is also a component of other structural proteins, such as tooth enamel and the proteins that make up the heart valves.

Threonine also plays a role in the formation of glycine and serine, which are other amino acids involved in synthesising important molecules such as neurotransmitters, hormones, and antibodies.

Threonine is also involved in the metabolism of lipids. It helps in the formation of phosphatidylcholine, which is an important component of cell membranes.

In addition, Threonine is also involved in regulating the immune system and is a component of several antibodies involved in the defence against pathogens.

Additional functions of threonine in the body include:

• Protein synthesis: Threonine is an essential component of many proteins in the body, it is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Nervous system function: Threonine is important for the formation of the structural proteins that make up the nervous system, including myelin sheaths, which protect nerve cells, and also for the maintenance of the structural integrity of the central nervous system.
• Immune function: Threonine plays a role in maintaining the integrity of the immune system, by helping to form antibodies and supporting the production of white blood cells, which help to fight off infections and illnesses.
• Metabolism of lipids: Threonine plays a role in the metabolism of lipids, by helping to lower cholesterol levels and reduce the risk of heart disease.
• Energy production: Threonine is involved in the production of energy-rich molecules such as ATP, which is important for energy metabolism and physical performance.
• Detoxification: Threonine is important for liver function, which is the main organ responsible for detoxifying the body, it's also involved in the production of key enzymes that are important for detoxifying the body.

In summary, Threonine plays a vital role in several metabolic pathways that are critical for overall health, including the formation of collagen and elastin, other structural proteins, formation of glycine and serine, metabolism of lipids, regulation of the immune system, and it is also a component of several antibodies that are involved in the defence against pathogens.

Adequate intake of threonine is important for maintaining good health and preventing deficiencies. It's particularly important for people with a diet that is deficient in threonine, people recovering from injuries, and people with certain liver conditions, as they require extra threonine for growth and repair and for liver function.

Tryptophan

Tryptophan is an essential amino acid, which means that it is a building block of proteins and cannot be produced by the body. It must be obtained through diet.

Tryptophan’s role in metabolism.

Tryptophan plays a vital role in several metabolic pathways that are critical for overall health and well-being.

One of the main roles of Tryptophan in metabolism is in the synthesis of serotonin, a neurotransmitter that is involved in the regulation of mood, sleep, and appetite. The body converts Tryptophan into serotonin, which helps regulate these brain functions.

Tryptophan also plays a role in the synthesis of melatonin, a hormone that is involved in the regulation of the sleep-wake cycle. It is also involved in the formation of niacin, a B-vitamin important for overall health.

Tryptophan is also involved in the regulation of the immune system. It helps to promote the production of antibodies and other immune cells that help defend the body against pathogens.

In addition, Tryptophan is also involved in the regulation of blood sugar levels and the growth and repair of tissues.

Additional functions of tryptophan in the body include:

• Protein synthesis: Tryptophan is an essential component of many proteins in the body, it is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Serotonin synthesis: Tryptophan is a precursor for the production of the neurotransmitter serotonin, which is important for the regulation of mood, sleep, and appetite.
• Melatonin synthesis: Tryptophan also is a precursor for the production of the hormone melatonin, which helps to regulate sleep and wake cycles.
• Immunomodulation: Tryptophan plays a role in regulating the immune system, it may have some potential benefits in treating conditions such as rheumatoid arthritis and other autoimmune disorders.
• Appetite control: Tryptophan has been found to have an effect on appetite control, by promoting feelings of fullness and reducing the risk of overeating.
• Pain relief: Tryptophan can be converted into serotonin and melatonin, which can act as natural pain relievers and can help to relieve pain caused by different conditions such as headaches, menstrual cramps, and other types of pain.

In summary, Tryptophan plays a vital role in several metabolic pathways that are critical for overall health, including the synthesis of serotonin, melatonin, niacin, regulation of the immune system, regulation of blood sugar levels and the growth and repair of tissues.

Adequate intake of tryptophan is important for maintaining good health and preventing deficiencies. It's particularly important for people with certain mood or sleep disorders, or people with conditions that affect the immune system, as they may require extra tryptophan for growth and repair and to regulate the levels of serotonin and melatonin.

Valine

Valine is an essential amino acid, which means that it is a building block of proteins and cannot be produced by the body. It must be obtained through diet. Valine is one of the three branched-chain amino acids (BCAA), along with leucine and isoleucine

Valine’s role in metabolism

Valine plays a vital role in several metabolic pathways that are critical for overall health and well-being.

One of the main roles of Valine in metabolism is in the maintenance of muscle tissue. Valine is one of the three branched-chain amino acids (BCAA), along with leucine and isoleucine, that are critical for muscle growth and repair. Valine is also involved in the regulation of blood sugar levels by providing energy to the muscles when glucose is not available.

Valine is also involved in the regulation of the immune system, it helps to promote the production of antibodies and other immune cells that help defend the body against pathogens.

In addition, Valine is also involved in the regulation of nitrogen balance, which is important for overall health.

Additional functions of valine in the body include:

Protein synthesis: Valine is an essential component of many proteins in the body, it is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.

Energy production: Valine plays a role in the production of glucose, which is an important source of energy for the body. It also helps in regulating blood sugar levels which can help maintain energy levels.

Muscle repair and maintenance: Valine is required for the repair and growth of muscle and other tissues. It also plays a role in wound healing and in the formation of red blood cells.

Nervous system function: Valine is important for the formation of the structural proteins that make up the nervous system, including myelin sheaths, which protect nerve cells, and also for the maintenance of the structural integrity of the central nervous system.

Endurance exercise: Valine can help promote endurance and recovery during exercise, and it can help reduce muscle damage and fatigue, promoting muscle protein synthesis and repairing muscle tissue.

Appetite control: Valine has been found to have an effect on appetite control, by promoting feelings of fullness and reduce the risk of overeating.

In summary, Valine plays a vital role in several metabolic pathways that are critical for overall health, including the maintenance of muscle tissue, regulation of blood sugar levels, regulation of the immune system, and regulation of nitrogen balance.

Adequate intake of valine is important for maintaining good health and preventing deficiencies. It's particularly important for athletes and people recovering from injuries, as they require extra valine for growth and repair and to support muscle function and endurance.

Non-essential amino acids:

These are the amino acids that the body can produce on its own and do not need to be obtained through the diet. There are 11 non-essential amino acids:

Alanine

Alanine is a non-essential amino acid, which means that it is a building block of proteins and can be produced by the body.

Alanine’s role in metabolism

Alanine plays a role in several important metabolic pathways for overall health and well-being.

One of the main roles of Alanine in metabolism is in the regulation of blood sugar levels. Alanine is involved in the glucose-alanine cycle, a mechanism for transporting nitrogen and carbon between muscles and the liver, where it is converted into glucose and used as energy.

Alanine also plays a role in detoxifying harmful substances in the liver, which helps remove toxins by converting them into other molecules that can be excreted from the body.

Alanine is also involved in the regulation of acid-base balance in the body. When the body's pH levels become too low (acidic), Alanine is converted into pyruvate, which then neutralizes the acidity by producing bicarbonate ions.

In addition, Alanine is also used in the formation of important molecules such as creatine, which is used for energy production in muscles, and GABA (gamma-aminobutyric acid), which is a neurotransmitter involved in the regulation of brain activity.

Additional functions of alanine in the body include:

• Protein synthesis: Alanine is a component of many proteins in the body and is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Glucose metabolism: Alanine plays a role in glucose metabolism by helping to regulate blood sugar levels and insulin sensitivity.
• Energy production: Alanine is involved in the production of energy-rich molecules such as glucose and ATP, which is important for energy metabolism and physical performance.
• Detoxification: Alanine plays a role in the detoxification of the liver, helping to remove harmful substances from the body.
• Muscle function: Alanine is important for maintaining muscle function, it aids in the transport of nitrogen from the muscle to the liver, which helps to reduce muscle breakdown and improve muscle recovery.
• Antioxidant activity: Alanine is a precursor for the production of the antioxidant enzyme glutathione, which helps to protect cells from damage caused by free radicals.

In summary, Alanine plays a role in several important metabolic pathways for overall health and well-being, including regulating blood sugar levels, detoxification of harmful substances, regulation of acid-base balance, formation of creatine, and GABA.

Adequate intake of alanine is important for maintaining good health and preventing deficiencies. It's particularly important for people with conditions such as diabetes and liver disease, as they may require extra alanine for glucose metabolism and detoxification.

Asparagine

Asparagine is a non-essential amino acid, which means that it is a building block of proteins and can be produced by the body.

Asparagine role in metabolism

Asparagine plays a role in several important metabolic pathways for overall health and well-being.

Asparagine is required in the production of many proteins in addition to other roles. Asparagine helps break down toxic ammonia within cells and is important for protein modification.

Asparagine also plays a role in the regulation of the immune system, it is involved in the formation of white blood cells and other immune cells that help defend the body against pathogens.

In addition, Asparagine is also involved in the regulation of the central nervous system, and it is a precursor of several neurotransmitters, such as aspartate, which is involved in the transmission of nerve impulses.

Additional functions of asparagine in the body include:

• Protein synthesis: Asparagine is a component of many proteins in the body and is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Nervous system function: Asparagine is important for the formation of the structural proteins that make up the nervous system, including myelin sheaths, which protect nerve cells, and also for the maintenance of the structural integrity of the central nervous system.
• Red blood cell production: Asparagine plays a role in the formation of red blood cells, and in the transport of oxygen throughout the body.
• Detoxification: Asparagine plays a role in the detoxification of the liver by helping to remove harmful substances from the body.
• Antioxidant activity: Asparagine is a precursor for the production of the antioxidant enzyme asparagine synthetase, which helps to protect cells from damage caused by free radicals.
• Immune system function: Asparagine is involved in the immune system's response, and may help in fighting bacterial and viral infections.

In summary, Asparagine plays a role in several metabolic pathways that are important for overall health and well-being, including the formation of Asparagine, enzymes, regulation of the immune system, and regulation of the central nervous system, and it is a precursor of several neurotransmitters.

Adequate intake of asparagine is important for maintaining good health and preventing deficiencies. It's particularly important for people with conditions such as anaemia, as they may require extra asparagine for red blood cell production and people with liver diseases as they may require extra asparagine for detoxification.

Aspartic acid

Aspartic acid is a non-essential amino acid, which means that it is a building block of proteins and can be produced by the body.

Aspartic acid role in metabolism

Aspartic acid plays a role in several metabolic pathways important for overall health and well-being.

One of the main roles of aspartic acid in metabolism is in the formation of aspartate. A compound involved in the biosynthesis of various amino acids and other molecules. Aspartate is also a component of several enzymes involved in various metabolic reactions.

Aspartic acid also plays a role in the regulation of the immune system, it is involved in the formation of white blood cells and other immune cells that help defend the body against pathogens.

In addition, Aspartic acid is also involved in the regulation of the central nervous system. It is a precursor of several neurotransmitters, such as glutamate and GABA (gamma-aminobutyric acid), which are involved in transmitting nerve impulses and regulating brain activity.

Aspartic acid also plays a role in the detoxification of harmful substances in the liver, where it helps to remove toxins by converting them into other molecules that can be excreted from the body.

Additional functions of aspartic acid in the body include:

• Protein synthesis: Aspartic acid is a component of many proteins in the body, and it helps with the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Energy metabolism: Aspartic acid is involved in the metabolism of carbohydrates and in the production of energy-rich molecules such as ATP, which is important for energy metabolism and physical performance.
• Detoxification: Aspartic acid plays a role in the detoxification of the liver by helping to remove harmful substances from the body, it also helps to neutralize excess levels of ammonia which can be toxic to the body.
• Hormone and neurotransmitter production: Aspartic acid is involved in the production of hormones such as luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and also neurotransmitters such as GABA and aspartate.
• Antioxidant activity: Aspartic acid acts as an antioxidant, it helps to protect cells from damage caused by free radicals, which can lead to aging and chronic diseases.
• Brain function: Aspartic acid is important for the brain function, it helps to regulate neural activity and also to promote memory and learning.

In summary, Aspartic acid plays a role in several metabolic pathways that are important for overall health and well-being, including the formation of aspartate, enzymes, regulation of the immune system, regulation of the central nervous system, detoxification of harmful substances, and it is a precursor of several neurotransmitters such as glutamate and GABA.

Adequate intake of aspartic acid is important for maintaining good health and preventing deficiencies. It's particularly important for people with liver diseases as they may require extra aspartic acid for detoxification, and those with certain endocrine disorders who may need more of this amino acid to support hormone production.

Cysteine

Cysteine is a non-essential amino acid, which means that it can be produced by the body and is also obtained through diet.

Cysteine’s role in metabolism

Cysteine plays a role in several important metabolic pathways for overall health and well-being. One of the main roles of Cysteine in metabolism is in the formation of the antioxidant glutathione. Glutathione is an important antioxidant that helps to protect cells and tissues from damage caused by free radicals. Cysteine also plays a role in detoxifying harmful compounds, such as heavy metals and xenobiotics, by supporting the activity of detoxifying enzymes in the liver.

Cysteine is also important for the formation of other critical molecules, such as collagen, keratin, and elastin which are essential for the structural integrity of skin, hair, and nails. It is also involved in the formation of the antioxidant enzymes, including catalase and peroxidase.

Cysteine also has a role in the regulation of the immune system, it is a component of several antibodies that are involved in the defence against pathogens. It also plays a role in the regulation of inflammatory response and supporting the health of the respiratory system.

Additional functions of cysteine in the body include:

• Protein synthesis: Cysteine is a component of many proteins in the body and is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Antioxidant activity: Cysteine is a precursor for the production of the antioxidant enzyme glutathione, which helps to protect cells from damage caused by free radicals.
• Detoxification: Cysteine plays a role in the detoxification of the liver by helping to remove harmful substances from the body.
• Immune system function: Cysteine is involved in the immune system's response and may help in fighting bacterial and viral infections.
• Hair and nail growth: Cysteine is important for the formation and maintenance of keratin, which is a protein that is found in hair and nails.
• Cardiovascular health: Cysteine has been suggested to have a potential benefit on cardiovascular health by reducing oxidized LDL cholesterol and by preventing of atherosclerosis.

In summary, Cysteine plays a vital role in several metabolic pathways that are critical for overall health, including the formation of the antioxidant glutathione, detoxification of harmful compounds, formation of collagen, keratin, and elastin, regulation of the immune system, regulation of inflammatory response and supporting the health of the respiratory system.

Adequate intake of cysteine is important for maintaining good health and preventing deficiencies. It's particularly important for people with conditions such as liver disease, as they may require extra cysteine for detoxification and for people with certain type of hair and nail problems, as they may require extra cysteine for keratin production.

Glutamine

Glutamine is a non-essential amino acid, which means that it can be produced by the body and is also obtained through diet.

Glutamine’s role in metabolism

Glutamine plays a role in several important metabolic pathways for overall health and well-being. One of the main roles of Glutamine in metabolism is in the maintenance of the balance of nitrogen and carbon in the body. It is also an important source of energy for cells in the immune system, gut, and other rapidly dividing cells.

Glutamine also plays a role in regulating acid-base balance and maintaining a healthy immune system by supporting the production and function of white blood cells. It helps to maintain the integrity of the gut lining and helps to regulate the release of growth hormone.

In addition, Glutamine is involved in the regulation of protein metabolism, helps to preserve muscle mass, and is also a precursor for synthesising other amino acids and nucleotides.

Glutamine is also an important neurotransmitter, it is involved in regulating brain activity and plays a role in regulating the central nervous system.

Some of the main functions of glutamine in the body include:

• Protein synthesis: Glutamine is a component of many proteins in the body and is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Energy metabolism: Glutamine plays a role in energy metabolism by providing fuel for cells, especially for cells in the gut, kidney and immune system.
• Immune system function: Glutamine is important for the immune system's response, and may help in fighting bacterial and viral infections, improving wound healing and in the recovery from illnesses.
• Intestinal health: Glutamine is an important nutrient for the cells that line the gut and can help to prevent damage to the gut barrier and supports gut-related health issues like diarrhoea and IBS.
• Acid-base balance: Glutamine helps to regulate the acid-base balance in the body by neutralizing acids produced during metabolism.
• Muscle mass maintenance: During periods of stress and physical activity, glutamine can help preserve muscle mass, in part by helping to provide energy to muscle cells, it also aids in recovery after intense exercise.

In summary, Glutamine plays a role in several metabolic pathways that are important for overall health and well-being, including the maintenance of the balance of nitrogen and carbon in the body, regulation of acid-base balance, maintenance of a healthy immune system, preservation of muscle mass, regulation of protein metabolism, and it acts as a precursor for the synthesis of other amino acids and nucleotides. It is also an important neurotransmitter involved in regulating brain activity and the central nervous system.

Adequate intake of glutamine is important for maintaining good health and preventing deficiencies. It's particularly important for people with conditions such as gut-related issues, intense physical activity or injury recovery, people with certain type of illnesses, as they may require extra glutamine for immune system function, muscle mass maintenance and recovery.

Glutamic acid

Glutamic acid, also known as glutamate, is a non-essential amino acid, which means that it can be produced by the body and is also obtained through diet.

Glutamic acid’s role in metabolism

Glutamic acid, also known as glutamate, plays a role in several important metabolic pathways for overall health and well-being.

One of the main roles of glutamic acid in metabolism is as a neurotransmitter. It is involved in the transmission of nerve impulses in the brain and the central nervous system.

Glutamic acid also plays a role in regulating acid-base balance and maintaining a healthy immune system by supporting the production and function of white blood cells.

In addition, Glutamic acid is involved in the regulation of protein metabolism, it helps preserve muscle mass, and it is also a precursor for synthesising other amino acids and nucleotides.

Glutamic acid is also involved in the formation of the antioxidant glutathione, which helps to protect cells and tissues from damage caused by free radicals, which are molecules that can cause oxidative stress and lead to chronic diseases.

Additional functions of glutamic acid in the body include:

• Protein synthesis: Glutamic acid is a component of many proteins in the body, and is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Energy metabolism: Glutamic acid plays a role in energy metabolism by providing fuel for cells and in the regulation of blood sugar levels.
• Nervous system function: Glutamic acid is an important neurotransmitter and plays a critical role in the transmission of nerve impulses in the brain and nervous system.
• Cognitive function: Glutamic acid is thought to be involved in cognitive processes such as learning and memory.
• Antioxidant activity: Glutamic acid is a precursor for the production of the antioxidant enzyme glutathione, which helps to protect cells from damage caused by free radicals.
• Muscle mass maintenance: Glutamic acid plays a role in protein synthesis and in muscle metabolism and may contribute to muscle mass maintenance and repair.

In summary, Glutamic acid plays a role in several metabolic pathways that are important for overall health and well-being, including its role as a neurotransmitter, regulation of acid-base balance, maintenance of a healthy immune system, regulation of protein metabolism, and preservation of muscle mass. It acts as a precursor for the synthesis of other amino acids and nucleotides, and it is also involved in the formation of the antioxidant glutathione.

Adequate intake of glutamic acid is important for maintaining good health and preventing deficiencies. It's particularly important for people with conditions related to cognitive decline, nervous system disorders, and muscle wasting, as they may require extra glutamic acid for cognitive function, nerve impulses and muscle mass maintenance.

Glycine

Glycine is a non-essential amino acid, which means that it can be produced by the body and is also obtained through diet.

Glycine role in metabolism

Glycine plays a role in several important metabolic pathways for overall health and well-being. One of the main roles of Glycine in metabolism is in the formation of collagen and other structural proteins that provide support and strength to the skin, bones, and other tissues. It is also a component of haemoglobin, the protein in red blood cells that binds and carries oxygen.

Glycine also plays a role in the detoxification of harmful substances in the liver. It helps to remove toxins by converting them into other molecules that can be excreted from the body.

In addition, Glycine is also involved in the regulation of the immune system, it is a component of several antibodies involved in the defence against pathogens.

Glycine also plays a role in the regulation of the central nervous system. It acts as a neurotransmitter and is involved in regulating brain activity and the sleep-wake cycle.

Additional functions of glycine in the body include:

• Protein synthesis: Glycine is a component of many proteins in the body and is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Nervous system function: Glycine is important for the formation of the structural proteins that make up the nervous system and also helps to regulate nerve impulses in the brain and spinal cord.
• Muscle mass maintenance: Glycine plays a role in muscle metabolism, helps to preserve muscle mass, and improve strength, as well as aid recovery after exercise.
• Digestive health: Glycine acts as a natural laxative and helps in digestion by facilitating the production of stomach acid.
• Blood sugar regulation: Glycine plays a role in glucose metabolism and insulin sensitivity, thus it may help regulate blood sugar levels.
• Antioxidant activity: Glycine is a precursor for the production of the antioxidant enzyme glutathione, which helps to protect cells from damage caused by free radicals.

In summary, Glycine plays a role in several metabolic pathways that are important for overall health and well-being, including the formation of collagen, and haemoglobin, detoxification of harmful substances, regulation of the immune system, and regulation of the central nervous system.

Adequate intake of glycine is important for maintaining good health and preventing deficiencies. It's particularly important for people with conditions such as muscle wasting, poor digestion, and blood sugar imbalances, as they may require extra glycine for muscle mass maintenance, digestion and glucose metabolism.

Proline

Proline is a non-essential amino acid, which means that it can be produced by the body and is also obtained through diet.

Proline’s role in metabolism

Proline plays a role in several metabolic pathways important for overall health and well-being. One of the main roles of Proline in metabolism is in the formation of collagen and other structural proteins that provide support and strength to the skin, bones, and other tissues.

Collagen is the most abundant protein in the body and is a major component of connective tissue, tendons, ligaments, and skin. Proline is also an important component of elastin, which provides elasticity to the skin and other tissues.

Proline also plays a role in wound healing and tissue repair. It helps to promote the formation of new blood vessels and new tissue growth.

Proline is also involved in the regulation of the immune system, it is a component of several antibodies that are involved in the defence against pathogens.

Proline also plays a role in the regulation of the central nervous system. It acts as a neurotransmitter and is involved in regulating brain activity and the sleep-wake cycle.

Additional functions of proline in the body include:

• Protein synthesis: Proline is a component of many proteins in the body and is important for the production of collagen, which is a protein that is needed for the growth and repair of skin, bones, and connective tissue.
• Connective tissue health: Proline is important for maintaining the structural integrity of connective tissues such as skin, tendons and ligaments.
• Wound healing: Proline plays a role in the repair of damaged tissues, thus it may help in the wound healing process.
• Cartilage health: Proline is a key component of cartilage which is the tissue that cushions joints, proline may help to maintain healthy cartilage and prevent or slow down joint degeneration.
• Heart health: Proline may have a beneficial effect on heart health by helping to maintain the structural integrity of blood vessels.
• Immune system function: Proline may have an effect on immune system function by helping to fight off harmful pathogens and in maintaining a healthy balance of gut bacteria.

In summary, Proline plays a role in several metabolic pathways that are important for overall health and well-being, including the formation of collagen, elastin, wound healing, tissue repair, regulation of the immune system, and regulation of the central nervous system.

Adequate intake of proline is important for maintaining good health and preventing deficiencies. It's particularly important for people with conditions such as connective tissue disorders, joint problems, skin issues, and impaired immune function as they may require extra proline for connective tissue repair, wound healing, cartilage health, heart health and healthy gut bacteria balance.

Serine

Serine is a non-essential amino acid, which means that it can be produced by the body and is also obtained through diet.

Serine’s role in metabolism

Serine plays a role in several important metabolic pathways for overall health and well-being. One of the main roles of Serine in metabolism is in the formation of proteins and phospholipids, which are important components of cell membranes and other structures in the body.

Serine also plays a role in the synthesis of creatine, which is an important compound for energy metabolism in muscles. Additionally, Serine is involved in the metabolism of fats and glucose, and it is also a precursor for the synthesis of other compounds such as glycine, purines, and porphyrins.

Serine also plays a role in the regulation of the immune system, it is a component of several antibodies that are involved in the defence against pathogens.

Serine is also involved in the regulation of the central nervous system. It acts as a neurotransmitter and is involved in regulating brain activity, memory, and the sleep-wake cycle.

Additional functions of serine in the body include:

• Protein synthesis: Serine is a component of many proteins in the body, and is involved in the production of enzymes and hormones.
• Nervous system function: Serine is an important neurotransmitter and plays a critical role in the transmission of nerve impulses in the brain and nervous system.
• Cognitive function: Serine is involved in cognitive processes such as learning, memory and mood regulation.
• Immune system function: Serine is involved in the immune system's response, and may help in fighting bacterial and viral infections.
• Metabolism: Serine plays a role in the metabolism of fats and fatty acids, and in the biosynthesis of phospholipids, important components of cell membranes.
• Gene regulation: Serine is important for the proper regulation of gene expression and has been proposed to play a role in the development of certain types of cancer.

In summary, Serine plays a role in several important metabolic pathways for overall health and well-being, including the formation of proteins, phospholipids, creatine, fat and glucose metabolism, and regulation of the immune system and the central nervous system.

Adequate intake of serine is important for maintaining good health and preventing deficiencies. It's particularly important for people with conditions related to cognitive decline, nervous system disorders, immune dysfunction, lipid metabolism disorder and potentially certain types of cancer as they may require extra serine for cognitive function, nerve impulses, immune system function, lipid metabolism, and gene regulation.

Tyrosine

Tyrosine is a non-essential amino acid, which means that it can be produced by the body and is also obtained through diet.

Tyrosine’s role in metabolism

Tyrosine plays a role in several important metabolic pathways for overall health and well-being. One of Tyrosine's main roles in metabolism is synthesising the neurotransmitters dopamine, norepinephrine, and epinephrine. These neurotransmitters are important for regulating mood, motivation, attention, and other cognitive functions.

Tyrosine also plays a role in the synthesis of thyroid hormones, which are important for regulating metabolism and energy levels. Additionally, Tyrosine is a precursor for the synthesis of the pigment melanin, which provides colour to the skin, hair, and eyes.

Tyrosine is also involved in the regulation of the immune system, it is a component of several antibodies that are involved in the defence against pathogens.

Tyrosine is also involved in the regulation of the endocrine system. It helps to produce hormones that regulate metabolism and other physiological processes.

Additional functions of tyrosine in the body include:

• Protein synthesis: Tyrosine is a component of many proteins in the body, including structural proteins and enzymes.
• Nervous system function: Tyrosine is important for the formation of neurotransmitters such as dopamine and norepinephrine, which play a critical role in the transmission of nerve impulses in the brain and nervous system.
• Cognitive function: Tyrosine is involved in cognitive processes such as learning, memory, and attention.
• Melanin production: Tyrosine is a precursor for the production of the pigment melanin, which is responsible for skin, hair, and eye colour.
• Thyroid hormone synthesis: Tyrosine is an important component of thyroid hormones which are essential for growth, metabolism and regulation of body temperature.
• Stress response: Tyrosine may help to reduce the negative effects of stress on the body, by providing precursors to the catecholamines, which are involved in the stress response.

In summary, Tyrosine plays a role in several important metabolic pathways for overall health and well-being, including synthesising neurotransmitters, thyroid hormones, melanin, regulation of the immune system, and endocrine system.

Adequate intake of tyrosine is important for maintaining good health and preventing deficiencies. It's particularly important for people with conditions related to cognitive decline, nervous system disorders, hypothyroidism, or an increased stress response as they may require extra tyrosine for cognitive function, nerve impulses, melanin production, thyroid hormone synthesis and reducing stress response.