Health Markers

3-Hydroxykynurenine (3-OH-kynurenine) is a metabolite in the kynurenine pathway, which reflects the breakdown of the amino acid tryptophan. It serves as an intermediate compound during the conversion of tryptophan into important molecules, including the essential coenzyme NAD+ (nicotinamide adenine dinucleotide).

5-Hydroxyindoleacetate (5-HIAA) is a measure that reflects the breakdown of serotonin, a key neurotransmitter in the body. It is primarily used as a clinical marker, particularly for detecting and monitoring carcinoid tumors that may overproduce serotonin. Urinary 5-HIAA levels can also serve as an approximate indicator of the body’s overall serotonin levels.

Anti-Thyroglobulin (A-TG) antibodies are immune system proteins that target thyroglobulin, a vital protein in the thyroid gland involved in thyroid hormone production. Elevated A-TG levels often indicate autoimmune thyroid disorders such as Hashimoto’s thyroiditis or Graves’ disease. These conditions can affect thyroid function and overall health, making A-TG monitoring important for diagnosis and management.

Anti-Thyroid Peroxidase (A-TPO) antibodies are immune proteins that mistakenly target thyroid peroxidase, an enzyme essential for producing thyroid hormones. Elevated levels of A-TPO antibodies are often associated with autoimmune thyroid disorders such as Hashimoto’s thyroiditis and Graves’ disease, which can lead to either underactive or overactive thyroid function and affect overall health.

Adipate, also known as adipic acid, is a compound involved in lipid metabolism and serves as a biomarker for metabolic dysfunctions, especially those related to fatty acid oxidation. Its presence, often detected in urine or blood tests, can aid in diagnosing and monitoring metabolic conditions.

Albumin is the most abundant protein in human blood plasma and plays a key role in maintaining oncotic pressure, helping to keep fluid within blood vessels. It also binds and transports various substances in the blood, such as hormones, vitamins, and drugs. Produced by the liver, albumin levels in the blood serve as important indicators of liver function and nutritional status.

Alkaline phosphatase (ALP) is an enzyme present in several tissues throughout the body, especially in the liver, bones, kidneys, and digestive system. ALP plays an important role in breaking down proteins and in dephosphorylation processes. In the liver, it’s associated with bile ducts and is commonly used to help diagnose liver and bone conditions. Elevated ALP levels may indicate bile duct obstruction or bone disorders, while low levels can be linked to certain genetic conditions and malnutrition.

Alpha-ketoglutarate (AKG) is a key compound in the Krebs cycle, an essential metabolic pathway for energy production in cells. It plays a crucial role in converting nutrients into energy, amino acid metabolism, and nitrogen transport. Additionally, Alpha-ketoglutarate is involved in various cellular processes, including signaling and regulation....

ALT (Alanine Aminotransferase):ALT is an enzyme mainly found in the liver, where it helps metabolize proteins. When liver cells are damaged or inflamed, ALT is released into the bloodstream, increasing its levels. Measuring ALT is a common method to evaluate liver health, as elevated levels can indicate liver injury or disease, while normal levels typically reflect normal liver function.

Alanine aminotransferase (ALT) is an enzyme found mainly in the liver that plays a key role in protein metabolism and other essential metabolic processes. Elevated ALT levels in the blood can signal liver cell damage or inflammation, making it an important marker for assessing liver health.

Amylase is an enzyme involved in digestion, produced by the pancreas and salivary glands. Its primary function is to break down complex carbohydrates — such as starches and glycogen — into simpler sugars like maltose and glucose, which the body can easily absorb.

Beta-hydroxybutyrate (BHB) is a ketone body that reflects the body’s shift to using fat as a primary fuel source. Produced by the liver from fatty acids during fasting, carbohydrate restriction, or intense exercise, BHB provides an alternative energy supply — particularly for the brain — when glucose is limited. It is a key marker of ketosis, a metabolic state associated with fat metabolism.

Betaine is a compound found in foods such as beets and spinach. It plays key roles in the body by acting as a methyl donor in methylation processes, helping regulate cellular fluid balance, supporting liver health by preventing fat accumulation, and lowering homocysteine levels, which contributes to cardiovascular health.

Bilirubin is a yellow compound that reflects the breakdown of red blood cells in the body. It is transported to the liver, where it is processed and excreted into the bile. Healthy liver function ensures bilirubin is efficiently filtered from the blood and converted into a form that can be eliminated through the digestive system. Blood bilirubin levels serve as an important indicator of liver health, bile duct function, and red blood cell turnover.

Hematuria, or blood in the urine, is a finding that indicates the presence of red blood cells in the urine. It may be visible, giving the urine a pink, red, or cola-like color, or microscopic, detectable only through laboratory testing. This condition can arise from a wide range of causes, from minor issues to serious underlying diseases.

Carnitine is a naturally occurring compound that plays a key role in energy metabolism. It transports long-chain fatty acids into the mitochondria, where they are broken down to produce energy, and helps remove metabolic waste from cells. While the body can synthesize carnitine in the liver and kidneys, it is also obtained from dietary sources, primarily animal-based foods.

The cholesterol-to-HDL (Chol:HDL) ratio is a measure that reflects the balance between total cholesterol and high-density lipoprotein (HDL) cholesterol in the blood. This ratio is used to assess heart disease risk, with a lower ratio indicating a healthier balance and a reduced risk. It is often considered a more accurate indicator of cardiovascular health than total cholesterol levels alone.

Choline is an essential nutrient that plays a key role in many vital body functions. It helps maintain the structure of cell membranes, supports the production of the neurotransmitter acetylcholine for muscle control, memory, and mood, and aids in fat metabolism and liver health. Choline is also important for brain development, neural tube formation during pregnancy, DNA synthesis, and healthy nervous system function.

Cis-aconitate is an intermediate in the Krebs cycle, a central metabolic pathway involved in cellular energy production. It is formed during the conversion of citrate to isocitrate, a reaction catalyzed by the enzyme aconitase. The Krebs cycle plays a vital role in oxidizing nutrients to produce ATP, the main energy source for cells, and also supplies key building blocks for the synthesis of amino acids, nucleotides, and fatty acids.

Citramalate, also known as citramalic acid, is a compound that can be measured as a urinary marker to assess metabolic health. It is produced as a metabolic byproduct and may indicate bacterial imbalance or overgrowth in the gut. Elevated levels can also reflect potential disruptions in normal metabolic processes.

Citrate is a compound that plays a key role in the citric acid cycle, essential for energy production in aerobic organisms. It helps break down carbohydrates, fats, and proteins to produce ATP (energy). Citrate also supports the regulation of the body’s acid-base balance and contributes to kidney stone prevention by binding with calcium.

Creatine Kinase (CK) is an enzyme present in the heart, brain, skeletal muscles, and other tissues. Elevated CK levels in the blood indicate muscle damage, as the enzyme is released when muscle cells are injured. There are different forms of CK, including CK-MM found in skeletal muscle, CK-MB mainly in the heart, and CK-BB typically in the brain. Measuring CK levels is valuable for diagnosing and monitoring muscle damage, such as that caused by a heart attack (myocardial infarction).

Creatinine is a compound produced from muscle metabolism and serves as an important indicator of kidney function. It is generated from creatine, a molecule essential for energy production in muscles, and is filtered from the blood by the kidneys before being excreted in urine.

Cystathionine is a non-protein amino acid that serves as an important intermediate in the metabolism of the essential amino acids methionine and cysteine. It plays a key role in the transsulfuration pathway, where homocysteine is converted into cystathionine by the enzyme cystathionine β-synthase (CBS), and cystathionine is then further broken down into cysteine by the enzyme cystathionine γ-lyase (CSE).

Anti-Thyroid Peroxidase (A-TPO) antibodies are proteins produced by the immune system that target thyroid peroxidase, an enzyme essential for thyroid hormone production. Elevated levels of A-TPO antibodies may indicate autoimmune thyroid disorders, such as Hashimoto's thyroiditis or Graves' disease, which can disrupt thyroid function and affect overall health.

EBNA IgG is a marker that reflects the presence of antibodies against EBV (Epstein-Barr virus) nuclear antigen (EBNA), a protein produced during the later stages of infection. The presence of EBNA IgG antibodies generally indicates a past infection, as these antibodies develop several weeks to months after the initial infection and typically remain detectable for life. Testing for EBNA IgG is often used alongside VCA antibodies to differentiate between a current and past infection and to evaluate the stage of the infection.

EBV VCA is a protein component of the Epstein-Barr virus (EBV) that appears early during infection. Testing for VCA is an important marker for diagnosing both acute and chronic EBV infections.

eGFR (Estimated Glomerular Filtration Rate) is a measure that estimates how well the kidneys filter waste from the blood. It is calculated using serum creatinine levels along with factors like age, body size, and gender. eGFR is a key indicator of kidney function, helping to determine how effectively the kidneys are working. A lower eGFR suggests reduced kidney function, which may indicate kidney disease or damage.

Ethyl malonate (EM) is a compound that acts as a biomarker for certain metabolic diseases. Elevated levels of ethyl malonate in the body may indicate hereditary metabolic conditions, such as ethylmalonic encephalopathy, or disorders of fatty acid metabolism.

Gamma-glutamyl transferase (GGT) is an enzyme found throughout the body, with the highest levels in the liver. GGT plays an important role in glutathione metabolism, which is vital for antioxidant defense. It helps transfer amino acids and peptides across cell membranes. Elevated GGT levels are often used as a marker to detect liver damage, especially bile duct obstructions and liver conditions related to alcohol use.

Globulin is a group of blood proteins that play important roles in the body, including transporting hormones, lipids, vitamins, and minerals. They are also key components of the immune system, with some globulins functioning as antibodies that help defend against infections. Produced by the liver and immune system, globulin levels can provide insight into immune health, liver function, and nutritional status.

Glucose is a simple sugar and the primary source of energy for the body’s cells. It plays a vital role in metabolism, supporting brain function, muscle activity, and overall energy production. Blood glucose levels are carefully regulated by hormones such as insulin and glucagon. Imbalances in glucose levels can lead to conditions like diabetes, hypoglycemia, and hyperglycemia, impacting overall health and requiring proper management.

GOT, or Gamma-Glutamyl Transferase (GGT), is an enzyme found in various tissues of the body, with the highest levels in the liver. It plays a key role in glutathione metabolism, a vital antioxidant, and is involved in the transport of amino acids across cell membranes. GOT is commonly measured in blood tests and serves as an important marker of liver and biliary tract function.

HbA1c (Glycated Hemoglobin) is a biomarker that reflects the average blood glucose levels over the past two to three months. It forms when glucose binds to hemoglobin in red blood cells and serves as a key indicator for long-term blood sugar control. Elevated HbA1c levels suggest poor glucose regulation and are commonly used to diagnose and manage diabetes.

HDL (High-Density Lipoprotein) is a type of cholesterol often referred to as “good” cholesterol. It helps protect heart health by carrying excess cholesterol from the bloodstream to the liver, where it can be removed from the body. Higher HDL levels are associated with a lower risk of heart disease and stroke.

Homocysteine is a sulfur-containing amino acid produced during the metabolism of methionine, an essential amino acid. It plays a key role in methylation, detoxification, and cardiovascular function. Elevated homocysteine levels have been associated with increased risk of heart disease, stroke, cognitive decline, and pregnancy complications. Imbalances may be caused by deficiencies in B vitamins (especially B6, B12, and folate), impaired methylation, or genetic variants like MTHFR. Monitoring homocysteine levels can provide valuable insights into cardiovascular, neurological, and metabolic health.

Homovanillic acid (HVA) is a metabolite that reflects the breakdown of dopamine, a key neurotransmitter in the body. HVA levels serve as an important marker for evaluating dopamine activity. Changes in HVA can indicate shifts in dopamine function and are used to monitor the effectiveness of treatments targeting dopamine metabolism.

High-sensitivity C-reactive protein (hs-CRP) is a blood test that measures low levels of C-reactive protein (CRP), a key marker of inflammation in the body. Unlike standard CRP tests, hs-CRP can detect subtle inflammation, making it especially useful for evaluating the risk of cardiovascular diseases such as heart attacks and strokes. Elevated hs-CRP levels may indicate a higher risk of heart disease, even when other risk factors are not present.

Hydroxymethylglutarate (HMG), especially as β-hydroxy β-methylglutaryl-CoA (HMG-CoA), is a compound that plays two vital roles in the body. It is a key intermediate in cholesterol synthesis, necessary for creating cell membranes, steroid hormones, and bile acids. Additionally, in the liver, HMG-CoA contributes to producing ketone bodies, which serve as an alternative energy source during fasting, low-carbohydrate diets, or intense exercise when glucose levels are low.

IDO (Indoleamine 2,3-dioxygenase) is an enzyme involved in metabolizing the amino acid tryptophan through the kynurenine pathway. By depleting tryptophan, it can modulate immune responses, a mechanism that some tumors may use to evade immune detection. IDO is also implicated in psychiatric and neurodegenerative disorders and is influenced by inflammation and stress.

IgG (Immunoglobulin G) is a type of antibody that reflects the body’s long-term immune response. It is the most abundant antibody in the blood and plays a key role in defending against infections. In the context of Lyme disease, caused by the bacterium Borrelia burgdorferi, IgG antibodies are measured to evaluate past exposure or later stages of infection. Unlike IgM antibodies, which appear early, IgG antibodies develop more gradually and can persist in the body for extended periods, providing lasting immunity.

IgM (Immunoglobulin M) is a type of antibody that serves as the body’s first line of defense against infections. It plays a key role in the immune system’s early response by quickly recognizing and targeting invading pathogens. In diagnostic testing, IgM levels are measured to detect recent infections, such as Lyme disease caused by Borrelia burgdorferi. The presence of IgM antibodies in the blood typically indicates a recent exposure or active infection, providing important information about the early stages of immune response.

Isocitrate is a key intermediate in the Krebs cycle, an essential metabolic pathway for cellular energy production. It is formed from citrate and then converted into α-ketoglutarate, a step that helps generate NADH used for ATP synthesis. Isocitrate also connects multiple metabolic processes, including the production of amino acids, nucleotides, and fatty acids.

Ketones are substances produced when the body breaks down fats for energy, especially during low carbohydrate intake such as fasting or following a ketogenic diet. This process, called ketosis, primarily takes place in the liver and generates key ketones like beta-hydroxybutyrate, acetoacetate, and acetone. Ketones serve as an alternative energy source, particularly for the brain, but elevated levels can signal serious conditions like diabetic ketoacidosis (DKA) in people with diabetes.

KMO (Kynurenine 3-monooxygenase) is an enzyme that plays a key role in the kynurenine pathway, responsible for metabolizing the amino acid tryptophan. It helps regulate the balance of metabolites within this pathway, influencing processes that can affect brain health. KMO activity has been linked to neurological conditions such as Alzheimer’s disease, Huntington’s disease, and schizophrenia.

Kynurenic acid is a metabolite formed in the kynurenine pathway during the breakdown of the amino acid tryptophan. It functions in the nervous system as a neuroprotective agent and is of interest in neurological and psychiatric research. Imbalances in kynurenic acid levels have been associated with conditions such as schizophrenia and depression.

Kynurenine is a key metabolite in the breakdown of the essential amino acid tryptophan. It acts as a precursor to several important compounds, including neuroprotective kynurenic acid and neurotoxic quinolinic acid, and plays a crucial role in a range of physiological and pathological processes in the body.

Lactate, also called lactic acid, is a byproduct of anaerobic metabolism — the process of breaking down glucose for energy without sufficient oxygen, often during intense exercise. It is linked to muscle fatigue and the familiar “burn” sensation in strenuous activity. Lactate also participates in the Cori cycle, where it is converted back into glucose in the liver.

LDL (Low-Density Lipoprotein) is a type of cholesterol often referred to as “bad” cholesterol. It carries cholesterol particles through the bloodstream, and high levels can contribute to plaque buildup in the arteries. This buildup, known as atherosclerosis, can narrow and stiffen arteries, increasing the risk of heart disease and stroke.

The measurement of histamine in stool is a diagnostic test used to assess gastrointestinal conditions. Histamine is a compound involved in immune responses and inflammation. Elevated levels of histamine in stool may indicate allergic reactions, infections, or disorders affecting the gut’s immune system. Monitoring histamine in stool can help evaluate digestive health and guide treatment strategies.

Urinary leukocytes are white blood cells found in urine. They are typically absent or present in very small numbers, and higher levels often signal infection or inflammation in the urinary tract or kidneys. Their detection is an important marker for diagnosing urinary tract infections (UTIs) and other kidney-related conditions.

Malate, or malic acid, is a key compound involved in cellular metabolism, especially within the Krebs cycle in the mitochondria. It plays an essential role in energy production by being converted to oxaloacetate, a process that generates NADH, which is then used to produce ATP, the primary energy currency of the cell.

Methylmalonic acid (MMA) is a substance produced in the body during the metabolism of certain fats and proteins. It is a byproduct of methionine breakdown and is influenced by vitamin B12 levels. Elevated MMA levels can serve as an indicator of vitamin B12 deficiency.

Neopterin is a molecule produced by immune cells, particularly macrophages, in response to stimulation by interferon-gamma. It is considered a marker of immune system activation and inflammation. Elevated levels of neopterin in urine or blood can indicate increased immune activity, often seen in infections, autoimmune disorders, or chronic inflammatory conditions. Because it reflects cellular immune response, neopterin is sometimes used to monitor disease progression or immune system status.

Nicotinamide adenine dinucleotide (NAD) is a vital coenzyme present in all living cells. It plays a key role in cellular metabolism, especially in redox reactions, by cycling between its oxidized form (NAD⁺) and reduced form (NADH). Beyond energy production, NAD⁺ is essential for cell signaling, DNA repair, and regulating gene expression, making it critical for maintaining cellular health and function.

Urinary nitrates are chemical compounds typically absent or present only in small amounts in urine. Their presence can indicate a bacterial infection, such as a urinary tract infection (UTI), since certain bacteria can convert urinary nitrite into nitrate. Nitrate testing is a common diagnostic method for detecting UTIs.

Non-HDL cholesterol is a measure of all cholesterol types that can contribute to arterial plaque buildup, including LDL (low-density lipoprotein), VLDL (very low-density lipoprotein), and other atherogenic lipid particles. It is calculated by subtracting HDL (high-density lipoprotein), or "good" cholesterol, from total cholesterol. Non-HDL cholesterol is considered a more comprehensive indicator of cardiovascular risk than LDL cholesterol alone, as it reflects all harmful cholesterol particles.

Urinary protein (proteinuria) is a measure that reflects the presence of protein in the urine. Proteins, such as albumin, are essential components of the blood, but they are usually not present in urine in significant amounts. Elevated urinary protein can indicate kidney damage or disease, as healthy kidneys normally prevent substantial protein loss through urine.

PSA (Prostate-Specific Antigen) is a protein produced by the prostate gland and commonly measured in the blood as a marker for prostate health. Elevated PSA levels may indicate prostate cancer but can also result from non-cancerous conditions such as benign prostatic hyperplasia or prostatitis.

PSA, or Prostate-Specific Antigen, is a protein produced by the prostate gland. Measuring PSA levels in the blood helps screen for prostate health, as elevated levels may indicate prostate cancer. However, higher PSA can also result from non-cancerous conditions such as benign prostatic hyperplasia or prostatitis.

The PSA ratio, or free-to-total PSA ratio, is a measure that reflects the proportion of free prostate-specific antigen (PSA) to total PSA in the blood. It is calculated by dividing the free PSA (unbound to proteins) by the total PSA (free plus protein-bound), then multiplying by 100 to express it as a percentage. This ratio helps distinguish between benign prostate conditions and prostate cancer, especially in men with moderately elevated total PSA levels.

Pyruvate is a key compound in cellular metabolism formed as the end product of glycolysis when glucose is broken down. It plays a central role in energy production by entering the citric acid cycle under oxygen-rich conditions. When oxygen is low, such as during intense exercise, pyruvate is converted into lactate to support continued ATP (energy) production. Additionally, pyruvate is involved in gluconeogenesis and serves as a precursor for amino acid synthesis.

Quinolinic acid is a metabolite in the kynurenine pathway, which is involved in the metabolism of the amino acid tryptophan. It plays a key role as an excitotoxin in the central nervous system. Elevated levels of quinolinic acid have been linked to neurological conditions such as Alzheimer’s disease, Huntington’s disease, epilepsy, and certain psychiatric disorders including depression.

S-Adenosylmethionine (SAMe) is a naturally occurring compound found in all cells, formed from methionine and ATP. It plays a vital role in methylation processes, neurotransmitter production affecting mood, joint health, and liver function. SAMe is commonly used as a supplement to support conditions such as depression, osteoarthritis, and liver disorders.

The SAMe/SAH ratio is a measure that reflects the balance between two important compounds in the body — S-Adenosylmethionine (SAMe) and S-Adenosylhomocysteine (SAH). SAMe serves as a key methyl donor in many biochemical processes, while SAH is produced after SAMe donates a methyl group. A higher SAMe/SAH ratio indicates strong methylation capacity, which supports healthy cellular function and overall well-being.

Suberic acid, also called octanedioic acid, is a dicarboxylic acid that serves as a metabolic marker in the body. In biological and physiological contexts, it is mainly associated with fatty acid metabolism. Elevated levels of suberic acid can signal metabolic disorders, particularly those affecting fatty acid oxidation, such as medium-chain acyl-coenzyme A dehydrogenase (MCAD) deficiency.

Succinate is a key metabolic intermediate that plays an essential role in the Krebs cycle, the process by which cells produce energy. It helps convert nutrients into ATP, the primary energy source for cellular functions. Beyond energy production, succinate also participates in amino acid and fatty acid synthesis and acts as a signaling molecule that influences inflammation and the body’s response to low oxygen levels.

Cholesterol is a waxy, fat-like substance found in all cells of the body and is essential for producing hormones, vitamin D, and digestive substances. While the body makes all the cholesterol it needs, it is also present in animal-based foods such as meat and dairy. There are two main types: low-density lipoprotein (LDL), or “bad” cholesterol, which can contribute to plaque buildup in arteries, and high-density lipoprotein (HDL), or “good” cholesterol, which helps remove excess cholesterol from the bloodstream.

Total Iron Binding Capacity (TIBC) is a blood test that reflects the blood's capacity to bind and transport iron through transferrin — the main iron-carrying protein. It provides an indirect measure of available transferrin and is commonly used alongside other iron tests to help assess iron deficiency, anemia, or iron overload conditions.

Total protein is a measure that reflects the combined levels of two major blood proteins — albumin and globulin. Albumin, the most abundant protein in blood plasma, helps maintain oncotic pressure and transports various substances, while globulins play key roles in immune response, blood clotting, and other functions. Total protein levels provide important insights into nutritional status as well as liver and kidney health.

Transferrin saturation is a measure that reflects the percentage of transferrin — a blood protein that transports iron — that is actually bound to iron. It helps assess how effectively iron is being carried and utilized in the body. This marker is useful for identifying iron deficiency or iron overload, and is typically calculated using serum iron and total iron-binding capacity (TIBC). Low levels may suggest iron deficiency, while high levels can indicate conditions such as hemochromatosis.

Transglutaminase IgG (tTG-IgG) is a blood test that detects IgG antibodies against tissue transglutaminase, an enzyme in the intestinal lining. It is mainly used to help diagnose celiac disease, especially in individuals with IgA deficiency or unclear tTG-IgA results, by indicating an immune reaction to gluten.

Triglycerides are a type of fat (lipid) found in the bloodstream and serve as a major form of energy storage. Excess calories from food are converted into triglycerides and stored in fat cells, then released by hormones for energy between meals. Elevated triglyceride levels, especially when combined with high LDL or low HDL cholesterol, are linked to a higher risk of atherosclerosis, heart attack, and stroke.

Trimethylamine (TMA) is a volatile organic compound produced in the gut by bacterial fermentation of dietary nutrients such as choline, L-carnitine, and lecithin. Normally, TMA is rapidly converted in the liver to trimethylamine N-oxide (TMAO), which is less toxic. However, elevated TMA levels can indicate imbalances in the gut microbiome or impaired liver detoxification capacity. High TMA is also associated with trimethylaminuria, a rare metabolic disorder that causes a strong body odor. Monitoring TMA provides insight into gut microbial activity, protein metabolism, and liver function.

Trimethylamine N-oxide (TMAO) is a compound produced in the liver from trimethylamine (TMA), which is generated by gut bacteria during the digestion of nutrients like choline, L-carnitine, and phosphatidylcholine. Elevated levels of TMAO have been linked to an increased risk of cardiovascular disease, kidney dysfunction, and inflammation. TMAO serves as a valuable marker for assessing metabolic health and the impact of gut microbiota on systemic disease risk. Lifestyle and diet, especially red meat and eggs, can significantly influence TMAO levels. Monitoring TMAO may help identify hidden risks even when other conventional markers appear normal.

Urea is a waste product formed in the liver through the breakdown of proteins. After formation, it is transported to the kidneys and eventually excreted in the urine. Measuring urea levels in the blood, often called blood urea nitrogen (BUN), is a common test used to evaluate kidney function. Elevated blood urea levels can indicate impaired kidney function or other issues affecting waste processing and excretion.

Urine density, also called urine specific gravity, is a measure of the concentration of solutes in the urine. It reflects the kidney’s ability to concentrate or dilute urine and serves as an indicator of hydration status and kidney function. While normal values can vary, deviations may indicate dehydration, overhydration, or underlying kidney disorders.

Urobilinogen in urine is a by-product of red blood cell breakdown, formed in the intestines from bilirubin and excreted in the urine. It is normally found in low concentrations and serves as an indicator of liver function and health. Abnormally high or low levels may indicate liver disease or blood-related conditions.

Vanillylmandelic acid (VMA) is a metabolite formed from the breakdown of catecholamines such as adrenaline, noradrenaline, and dopamine. It is used as a clinical marker to assess catecholamine activity, with levels typically measured in urine. Various factors, including certain foods and medications, can influence VMA levels.

Xanthurenate is a metabolite formed during the breakdown of the amino acid tryptophan through the kynurenine pathway. Its levels can reflect vitamin B6 (pyridoxine) status, as this vitamin acts as a vital cofactor in the process. Elevated xanthurenate may indicate a deficiency in vitamin B6.