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Optimal range: 6 - 45 qM/g creatinine
LEARN MOREOptimal range: 36.3 - 119.2 umol/L
Arginine is a conditionally essential amino acid that is critical for your cardiovascular health and detoxification functions. The amino acid, arginine, is used to make the powerful blood vessel regulator, nitric oxide. Nitric oxide acts to lower blood pressure.
Optimal range: 0 - 26.4 nmol/mg Creatinine
→ Arginine is a precursor of urea, nitric oxide, polyamines (putrescine, spermidine, spermine and agmatine), proline, glutamate, and creatine.
→ Levels may drop with increased need, or in renal or small intestine dysfunction.
→ Synthesis of arginine depends on citrulline levels and is less regulated by dietary arginine. Supplementation with citrulline increases plasma arginine and the production of nitric oxide (NO).
→ Arginine supplementation may lower blood pressure.
→ Metabolism of elevated arginine levels is dependent on glycine availability.
→ Plasma arginine and ornithine increased, while citrulline remained stable, following watermelon juice intake, a rich source of citrulline.
Optimal range: 0 - 6 mmol/mol creatinine
Arginine is found in all protein foods and is very abundant in seeds and nuts. It is considered a semi-essential amino acid during early development, infection/inflammation, or renal and/or intestinal impairment. It has many functions in the body including:
- ammonia disposal in the urea cycle
- immune function
- stimulation of insulin release
- muscle metabolism (creatine/creatinine precursor)
- nitric oxide (NO) formation
- glutamic acid and proline formation
- glucose/glycogen conversion
- stimulation of the release of growth hormone, vasopressin, and prolactin
- wound healing
Because arginine is a precursor for nitric oxide synthesis, it is often used therapeutically in cardiovascular disease for its vasodilatory effects.
Optimal range: 36.9 - 112.2 nmol/ML
LEARN MOREOptimal range: 29 - 137 µmol/L , 2.9 - 13.7 µmol/dL
Arginine is a conditionally essential amino acid that is critical for your cardiovascular health and detoxification functions. The amino acid, arginine, is used to make the powerful blood vessel regulator, nitric oxide. Nitric oxide acts to lower blood pressure.
Optimal range: 81.6 - 249 nmol/ML
Physiological Function:
L-Arginine is a conditionally essential amino acid found in the diet. It is a dietary supplement used mostly by athletes because it is the amino acid that directly produces nitric oxide via the nitric oxide synthase enzymes.
Arginine helps heal injuries, aids kidneys in removing waste, and boosts immune system function.
Optimal range: 3 - 43 micromol/g creatinine
Arginine is a conditionally essential amino acid that is critical for your cardiovascular health and detoxification functions. The amino acid, arginine, is used to make the powerful blood vessel regulator, nitric oxide. Nitric oxide acts to lower blood pressure.
Optimal range: 0.1 - 51.2 umol/g Cr
Argininosuccinate (aka Arginosuccinic acid) is a basic amino acid. Some cells synthesize it from citrulline, aspartic acid and use it as a precursor for arginine in the urea cycle or Citrulline-NO cycle. The enzyme that catalyzes the reaction is argininosuccinate synthetase. Argininosuccinic acid is a precursor to fumarate in the citric acid cycle via argininosuccinate lyase. Defects in the argininosuccinate lyase enzyme can lead to argininosuccinate lyase deficiency, which is an inborn error of metabolism.
Optimal range: 0 - 3 umol/L
Argininosuccinate (aka Arginosuccinic acid) is a basic amino acid. Some cells synthesize it from citrulline, aspartic acid and use it as a precursor for arginine in the urea cycle or Citrulline-NO cycle. The enzyme that catalyzes the reaction is argininosuccinate synthetase. Argininosuccinic acid is a precursor to fumarate in the citric acid cycle via argininosuccinate lyase. Defects in the argininosuccinate lyase enzyme can lead to argininosuccinate lyase deficiency, which is an inborn error of metabolism.
Optimal range: 0 - 29.5 nmol/mg Creatinine
It is not normally detectable in healthy adults. Adult argininosuccinate lyase insufficiencies are typically treated with a lower protein/higher carbohydrate diet, arginine supplementation, and avoidance of fasting.
Optimal range: 0 - 14.2 nmol/ML
LEARN MOREOptimal range: 23.8 - 42.9 pmol/min/ml
Aromatic L-amino acid decarboxylase (AADC) enzyme plays a crucial role in the human body's ability to process certain amino acids into neurotransmitters, which are chemical messengers that transmit signals in the brain and other areas of the nervous system.
AADC acts on L-amino acids, particularly those with an aromatic side chain, such as L-dopa (levodopa), converting them into dopamine, and 5-hydroxytryptophan into serotonin. These neurotransmitters are essential for regulating mood, movement, and autonomic functions within the body.
The assessment of AADC enzyme activity can help diagnose AADC deficiency—a rare but serious condition that affects neurotransmitter synthesis, leading to developmental delays, movement disorders, and autonomic dysfunction. By evaluating this marker, healthcare providers can gain insights into a patient's neurotransmitter production capabilities, guiding diagnosis and treatment strategies for conditions influenced by neurotransmitter levels. This makes the Aromatic L-amino acid decarboxylase enzyme a significant point of interest for researchers and clinicians alike, offering a window into the complex interplay of genetics, enzyme activity, and neurological health.
Reference range: Very Low, Low, Moderate, High, Very High
LEARN MOREOptimal range: 0 - 0.2 mg/kg Dry Wt
Fecal Arsenic (As) provides an estimate of a very recent oral exposure to the element, and to a much lesser extent, As that has been excreted from the body in bile. Inorganic As accumulates in hair, nails, skin, thyroid gland, bone and the gastrointestinal tract. Non-toxic organic As (shellfish) is rapidly excreted, primarily in the urine and to a lesser extent in the feces.
Optimal range: 0 - 9 ug/L
Exposure to arsenic-laden drinking water can induce symptoms of gastroenteritis and lead to cancer, diabetes, and neurological and vascular dysfunction. Long-term arsenic exposure in drinking water shows a dose-response relationship to carotid atherosclerosis. The mechanism involves the induction of expression of genes coding inflammatory mediators. Arsenic has also been linked to dermatosis and cancers of the skin, bladder, and lung. Dietary arsenic is contributed by various foods including cereals and breads, 18.1%; starchy vegetables, 14.9%; and meats and fish, 32.1% of total average daily intake.
Optimal range: 0 - 11.9 ug/g
Arsenic is a naturally occurring element found in soil, water, and food, with exposure most often coming from contaminated groundwater, rice, grains, seafood, or certain workplaces. While small amounts are common in daily life, elevated arsenic in urine suggests recent or ongoing exposure at a level that may increase health risks. Long-term exposure is linked to skin changes, digestive upset, fatigue, immune suppression, kidney and liver stress, cardiovascular problems, and higher cancer risk, especially from inorganic arsenic in water or food. Testing for arsenic helps identify hidden sources of exposure so you can take steps to reduce risk—such as using filtered water, limiting high-arsenic foods, and avoiding older pesticides or arsenic-treated wood. If results are elevated, working with a healthcare provider familiar with environmental medicine can help guide safe detox and long-term protection.
Optimal range: 0 - 0.01 Units
Arsenic circulating in the blood will bind to protein by formation of a covalent complex with sulfhydryl groups of the amino acid cysteine. Keratin, the major structural protein in hair and nails, contains many cysteine residues and, therefore, is one of the major sites for accumulation of arsenic. Since arsenic has a high affinity for keratin, the concentration of arsenic in hair is higher than in other tissues. Arsenic binds to keratin at the time of exposure, "trapping" the arsenic in hair. Therefore, hair analysis for arsenic is not only used to document that an exposure occurred, but when it occurred. Hair collected from the nape of the neck can be used to document recent exposure. Axillary or pubic hair is used to document long-term (6 months-1 year) exposure.
Optimal range: 0 - 0.06 µg/g
Elemental analysis provides a good estimate of exposure to inorganic arsenic (As). However, hair can be contaminated externally with As from air, water, dust, shampoos and soap. Inorganic As, and some organic As compounds, can cause toxicity. Some research suggests that As may beessential at extremely low levels but its function is not understood. Inorganic As accumulates inhair, nails, skin, thyroid gland, bone and the gastrointestinal tract. Organic As is rapidly excreted in the urine.