Hormones Glossary

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Aspartic Acid

Aspartic Acid, also known as aspartate, is an excitatory neurotransmitter in the brainstem and spinal cord. Aspartic acid is the excitatory counterpart to glycine, an inhibitory neurotransmitter. Low levels have been linked to feelings of fatigue and low mood, whereas high levels have been linked to seizures and anxiousness.

5 Alpha Reductase

An enzyme that converts testosterone, the male sex hormone, into the more potent dihydrotestosterone (DHT).

Adrenal Fatigue

A putative health disorder in which the adrenal glands are claimed to be exhausted and unable to produce adequate quantities of hormones, primarily cortisol. Also called hypoadrenia and adrenal insufficiency.


Not aging or appearing to age.


Multidimensional process of physical, psychological and social change in humans over time.


A hormone produced by the cortex of the adrenal gland, instrumental in the regulation of sodium and potassium reabsorption by the cells of the tubular portion of the kidney.

Alopecia Areata

Hair loss occurring in only one section.

Alzheimer’s disease

Also called SDAT (senile dementia Alzheimer’s type). This disease is characterized by a general loss of intellectual ability and impairment of memory, judgment and abstract thinking, as well as changes in personality. Other symptoms include loss of speech, disorientation and apathy. Alzheimer’s disease is the most common cause of dementia, rarely occurring before the age of 50. The disease takes from a few months to four or five years to progress to complete loss of intellectual function.


Any group of drugs that stimulate the central nervous system, resulting in elevated blood pressure, heart rate and other metabolic functions.

Anabolic Steroids

A class of steroid hormones related to the hormone testosterone. They increase protein synthesis within cells, which results in the buildup of cellular tissue (anabolism), especially in the muscles.


A steroid hormone, such as testosterone or androsterone, that promotes male characteristics.


The male counterpart of menopause, when the production of testosterone decreases and there are accompanying mental symptoms.


A condition marked by a deficiency of red blood cells or of hemoglobin in the blood, resulting in pallor and weakness.

Anti-Aging Medicine

Medicine focused on preventing, slowing, or reversing the effects of aging and helping people live longer, healthier, happier lives.


Distress or uneasiness of mind caused by fear of danger or misfortune; a state of apprehension.


An enzyme or complex of enzymes that promotes the conversion of an androgen (like testosterone) into estrogens (like estradiol).


A basic standard or level; guideline that can serve as a comparison or control.

Benign Prostatic Hyperplasia (BPH)

The increased size of the prostate in middle-aged and elderly men. Also referred to as nodular hyperplasia, benign prostatic hypertrophy or benign enlargement of the prostate (BPE).


An ingredient used to bind together two or more other materials (ingredients) in mixtures: a binder used in medication.


The degree to which or rate at which a hormone or other substance is absorbed or becomes available at the site of physiological activity. (bio-available)


Identical to the substance in the human body; bioidentical estrogen.

Bioidentical Hormone Replacement Therapy (BHRT)

Used to describe hormone supplementation for female menopause with estradiol and progesterone, or male menopause with testosterone, but can also include dehydroepiandrosterone (DHEA), estriol or estrone. BHRT is part of a growing practice of restorative endocrinology of restoring several well-known human hormones to optimal levels and effects with the use of bioidentical hormones.

Bioidentical Hormones

Substances with the exact same molecular structure as those made in the human body, which produce the same physiologic responses as the body’s natural hormones.

Blood Test

A Laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a needle, or via a fingerprick.

C-reactive protein (CRP)

An inflammatory marker – a protein that the body releases in response to inflammation. Thus, elevated levels of CRP in the blood mean that there is inflammation somewhere in the body. CRP is not normally present in the blood of a healthy patient. CRP levels can increase by as much as 1000-times with inflammation. Conditions that commonly lead to marked changes in CRP include infection, trauma, surgery, burns, inflammatory conditions, and advanced cancer. Moderate changes occur after strenuous exercise, heatstroke, and childbirth. Psychological stress and some psychiatric illnesses can cause small changes in CRP levels. CRP is the only inflammatory marker that has been found to be an indicator of heart health. Therefore, doctors often carry out a CRP test at the same time as cholesterol and other lipid tests to help predict a patient’s risk of heart attack.


A usually microscopic structure containing nuclear and cytoplasmic material enclosed by a semi-permeable membrane; the basic structural unit of all organisms.

Cell Membrane

The interface between the cellular machinery inside the cell and the fluid outside. A semi-permeable lipid bilayer found in all cells containing biological molecules, primarily proteins and lipids.

Central Sleep Apnea

A central nervous system disorder in which the brain signal for breathing is delayed. Often caused by injury or disease affecting the brain stem.

Circadian Rhythm

An approximate daily periodicity, a roughly 24-hour cycle in the biochemical, physiological or behavioral processes of living beings. These rhythms allow organisms to anticipate and prepare for precise and regular environmental changes.

Complete Blood Count

A test that gives information about the cells in a person’s blood including the white blood cells (leukocytes), red blood cells (erythrocytes) and platelets.


To produce or create by combining two or more ingredients or parts: pharmacists compounding prescriptions.

Compounding Pharmacy

A specialized pharmacy that hand makes individualized bioidentical hormone prescriptions. (compounding pharmacies)


To cause a substance to undergo a chemical change. (conversion)

Corpus Luteum

A yellow, progesterone-secreting mass of cells that forms from an ovarian follicle after the release of a mature egg.


A steroid hormone produced by the adrenal gland which regulates carbohydrate metabolism, stress and maintains blood pressure. Also called hydrocortisone.

Covalent Bonds

A form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms, or between atoms and other covalent bonds.

CreatinineCreatinine is a normalizing parameter used to calculate neurotransmitter levels. Creatinine is produced at a constant rate through the kidneys. Therefore, by using creatinine as the constant factor, spot urinary measurements can be performed with out having to factor in the patient’s hydration state, possible renal disorders or diuretic substances that may have been used.


The amount lacked; a shortage: an estrogen deficiency or vitamin deficiency.


Of, relating to, involving, or tending to cause degeneration; to diminish in quality, esp. for a former state of coherence, balance, integrity, etc.

Dehydroepiandrosterone (DHEA)

A steroid hormone naturally produced by the adrenal glands and sold in synthetic form as a nutritional supplement.


A condition of general emotional dejection and withdrawal; sadness greater and more prolonged than that warranted by any objective reason.

DHT (dihydrotestosterone)

A conversion of testosterone that is considered to be an aging-bio-marker. Among its affects are the appearance of body-hair, the loss of scalp hair and the onset of prostate gland problems.

Diagnostic Test

Any kind of medical test performed to aid in the diagnosis or detection of disease or poor health.


A disturbance in physical or mental health or functions.

Domino Effect

The cumulative effect that results when one event precipitates a series of like events.

DopamineDopamine is an excitatory and inhibitory neurotransmitter, depending on the dopaminergic receptor it binds to. It is derived from the amino acid tyrosine. Dopamine is the precursor to norepinephrine and epinephrine, which are all catecholamines. The function of dopamine is diverse but plays a large role in the pleasure/reward pathway (addiction and thrills), memory, and motor control. Dopamine, like norepinephrine and epinephrine, is stored in vesicles in the axon terminal. Dopamine plays a significant role in the cardiovascular, renal, hormonal, and central nervous systems. The dopaminergic neurons have dendrites that extend into various regions of the brain, controlling different functions through the stimulation of adrenergic and dopaminergic receptors (D1 ?D5). Common symptoms with low dopamine levels are loss of motor control, addictions, cravings, compulsions, and loss of satisfaction. When dopamine levels are elevated symptoms may manifest in the form of anxiety or hyperactivity. Some therapies utilize L-DOPA for parkinsonian symptoms which can also cause elevations in dopamine.

Dopamine MetaboliteAfter neuronal dopamine is released it is inactivated primarily via reuptake mechanisms that remove it from the synapse and the extraneuronal space and return it to the presynaptic dopaminergic neuron or adjacent noradrenergic neurons. Some of the enzymes that degrade dopamine are only found in specific regions of the body. As such some dopamine metabolites are only produced in specific tissues. Understanding how and where these enzymes function can provide valuable insight about how dopamine is functioning in specific regions of the body. In order to understand these functions one must first realize Monoamine oxidase (MAO) is an enzyme present within the cytoplasm of neurons that breaks down dopamine to DOPAL. DOPAL in turn is very rapidly converted to DOPAC by a second cytoplasmic enzyme aldehyde dehydrogenase (AD). Because both of these enzymes are primarily found inside neurons, DOPAC levels are dependent on the amount of cytoplasmic dopamine. Combined measurements of DOPAC and dopamine have been used to assess the activity of dopaminergic neurons. This combination provides additional information than either parameter alone because a large portion of DOPAC is formed from dopamine without ever being released to the synaptic cleft. This suggests that DOPAC may be more closely related to the presynaptic dopamine levels while dopamine and similarly HVA levels, another important metabolite of dopamine that is formed outside of the neuron via the actions of catechols-O-methyltransferase (COMT), are related to the rate of neuron signaling. Said another way, extracellular DOPAC is related to the amount of dopamine made and stored in the presynaptic neuron while extracellular dopamine levels are related to the rate of dopamine released via the depolarization of dopamine neurons.


The amount of medicine to be given.

Double blind

A type of scientific experiment in which neither the subjects nor the researchers know who is receiving an active substance and who is receiving a placebo. Researchers who do not know which subjects received the active substance then usually evaluate the data generated from the experiment. This type of experiment helps to eliminate personal bias from research.


The presence of uterine lining in other pelvic organs, esp. the ovaries, characterized by cyst formation, adhesions and menstrual pains.

Environmental Factors

Those determinants of disease that are not transmitted genetically and may determine the development of disease in those genetically predisposed to a particular condition. Environmental factors include stress, physical and mental abuse, diet, exposure to toxins, pathogens, radiation and chemicals found in almost all personal care products and household cleaners are common environmental factors that determine a large segment of non-hereditary disease.

EpinephrineEpinephrine, also known as adrenaline, is an excitatory neurotransmitter and hormone essential for lipolysis, which is a process in which the body metabolizes fat. Epinephrine is derived from the amine norepinephrine. As a neurotransmitter, epinephrine regulates attentiveness and mental focus. Epinephrine is synthesized from norepinephrine.As a hormone, epinephrine is secreted along with norepinephrine principally by the medulla of the adrenal gland. Heightened secretion can occur in response to fear or anger and will result in increased heart rate and the hydrolysis of glycogen to glucose. This reaction, referred to as the “fight or flight” response, prepares the body for strenuous activity. Epinephrine is used medicinally as a stimulant in cardiac arrest, as a vasoconstrictor in shock, as a bronchodilator and antispasmodic in bronchial asthma, and anaphylaxis. Commonly, epinephrine levels will be low due to adrenal fatigue (a pattern in which the adrenal output is suppressed due to chronic stress). Therefore, symptoms can be presented as fatigue with low epinephrine levels. Low levels of epinephrine can also contribute to weight gain and poor concentration. Elevated levels of epinephrine can be factors contributing to restlessness, anxiety, sleep problems, or acute stress.

Erectile Dysfunction

Difficulty in achieving or maintaining an erection of the penis; impotence.


The most powerful female hormone that occurs naturally. An estrogenic hormone produced by the ovaries and used in treating estrogen deficiency and certain menopausal and postmenopausal conditions.


An estrogenic hormone occurring in urine during pregnancy; used in conditions involving estrogen deficiency.


Any of several steroid hormones produced chiefly by the ovaries and responsible for the development and maintenance of female secondary sex characteristics.

Estrogen Dominance

A condition in which a person has excess amounts of estrogen in the body.


An estrogenic hormone produced by the ovarian follicles and found during pregnancy in urine and placental tissue; used in the treatment of estrogen deficiency and certain menopausal and postmenopausal conditions.


Weariness or exhaustion of the mind or body from labor, exertion, or stress.


A benign tumor composed of fibrous or muscle tissue, especially one that develops in the uterus.


A syndrome characterized by chronic pain in the muscles and soft tissues surrounding the joints, fatigue and tenderness at specific sites in the body. Also called fibromyalgia syndrome, fibromyositis, fibrositis.

Follicle Stimulating Hormone

A gonadotropic hormone of the anterior pituitary gland that stimulates the growth of follicles in the ovary and induces the formation of sperm in the testes.


Loss of remembrance or recollection; a ceasing to remember. Also called memory loss, foggy thinking, or foggy memory.

Free Radicals

Harmful molecules that cause damage in the body; leading factors in the development of blood vessel disease (atherosclerosis), cancer and other conditions. Byproducts of normal body processes, byproducts of the breakdown of certain medicines, found in pollutants.

GABAGABA is a true neurotransmitter and is the major inhibitory neurotransmitter of the brain, occurring in 30-40% of all synapses. GABA is second only to glutamate, the brain’s major excitatory neurotransmitter. The GABA concentration in the brain is 200-1000 times greater than that of the monoamines or acetylcholine. The primary function of GABA is to prevent overstimulation. It does so by compensating for glutamate activity.; When GABA activates its receptor it causes negative ions to flow into the cell preventing depolarization. Glutamate can depolarize the cell and form an action potential by causing positive ions to flow into the cell when it activates its receptors. Overall, GABA regulates the activity of glutamate by preventing depolarization of the cell, therefore, preventing overstimulation.


Secretion of milk from the breast of a non-lactating person.

Gamma-Aminobutyric Acid (GABA)

A neurotransmitter of the central nervous system that inhibits excitatory responses.

GlutamateGlutamate is the major excitatory neurotransmitter in the brain which is necessary for memory and learning. In fact, it is believed that 70% of the fast excitatory CNS synapses utilize glutamate as a transmitter. Excitatory neurotransmitters increase the activity of signal-receiving neurons and play a major role in controlling brain function. Glutamate exerts its effects on cells, in part, through three types of receptors that, when activated, allow the flow of positively charged ions into the cell. These include the ionotropic receptors: kianate, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), and N-methyl-D-aspartate (NMDA) receptors. There are also series metabotropic glutamate receptors that do not directly manipulate an ion channel.; Of the ionotropic receptors, the N-methyl-D-aspartate (NMDA) receptor plays a particularly important role in controlling the brain’s ability to adapt to environmental and genetic influences which is important for learning and memory.

GlycineGlycine is a principal inhibitory amino acid in the brainstem and spinal cord that regulates excitatory neurotransmission in much the same way as GABA. Glycine, much like GABA and taurine, can become elevated to compensate for elevations in excitatory neurotransmitters, primarily, glutamate and aspartic acid. This non-essential amino acid is common in protein-based foods, and can be synthesized metabolically from a number of different amino acids, including serine and threonine.; Curiously, glycine is a necessary cofactor in the activation of the glutamate receptor, NMDA. It seems paradoxical that a primarily inhibitory amino acid facilitates the activation of an excitatory receptor. It has been postulated that glycine’s inhibitory and excitatory actions are part of the many checks and balances the body has for regulating neurotransmission.

Growth Hormone (GH)

A hormone secreted by the pituitary gland. GH stimulates growth and repair of the body as well as the activities of the immune system. With age, GH release diminishes (also known as HGH or human growth hormone).


Abnormal enlargement of the breasts in a male.

Hair Loss

The medical description of the loss of hair from the head or body, sometimes to the extent of baldness, that is involuntary and unwelcome. In some cases, it is an indication of an underlying medical concern, such as iron deficiency. Also called alopecia.


The general condition of the body or mind with reference to soundness and vigor.

HistamineHistamine is an excitatory neurotransmitter involved in the sleep/wake cycle and inflammatory response. Depending on the receptor histamine activates a wide array of biological actions can occur. For instance, one receptor helps regulate the sleep/wake cycle whereas another receptor helps regulates norepinephrine, serotonin, and acetylcholine release. There are also other receptors that may be activated to induce inflammatory response, which is commonly associated with the exposure to an allergen.


Latin for a chemical messenger, such as growth hormone, testosterone or insulin.

Hormone Pellet Therapy

A sustainable delivery method or treatment option for bioidentical hormone therapy. Every three to six months a pellet made of bioidentical hormones is inserted just under the patient’s skin. The pellets, which contain customized levels of estradiol or testosterone, react to the needs of the body, so they actually dissolve releasing the bioidentical hormones as needed.

Hormone Therapy

The use of hormones in medical treatment. Also called hormonal therapy.

Hot Flash

A sudden feeling of feverish heat typically as a symptom of menopause. Also called a hot flush.


Pathologically excessive production of the thyroid hormones.


Diminished hormonal or reproductive functioning in the testes or the ovaries.


An area of the brain that is believed to be the command center for instructions to the endocrine system.


Deficient activity of the thyroid gland.


Surgical removal of part or all of the uterus. Also called surgical menopause.


Lack of proportion or relation between corresponding things: the condition is caused by a hormone imbalance.


Inability to obtain sufficient sleep, especially when chronic; difficulty in falling or staying asleep. Also called sleeplessness.

Interstitial Cystitis

A urinary bladder disease of unknown cause characterized by urinary frequency, urgency, pressure and/or pain in the bladder and/or pelvis. Also known as painful bladder syndrome (PBS).


An element required in small amounts for healthy growth and development. The thyroid gland requires iodine to synthesize thyroid hormones; a deficiency of the element leads to goiter.


Easily irritated or annoyed; readily excited to impatience or anger.

Irritable Male Syndrome

The term for a set of symptoms caused by a drop in testosterone levels in males. These symptoms are similar to those of the male menopause or andropause. One of the most consistent symptoms is anger and sullen withdrawal present in men between the ages of 40 and 60.


A small surgical instrument, usually sharp-pointed and two-edged, for making small incisions, opening abscesses, etc.


Sexual urge or desire.


A long individual life; great duration of individual life.

Luteinizing Hormone

A hormone produced by the anterior lobe of the pituitary gland that stimulates ovulation and the development of the corpus luteum in the female and the production of testosterone by the interstitial cells of the testes in the male.


Any of the various white blood cells, including B-cells and T-cells, that function in the body’s immune system by recognizing and deactivating specific foreign substances called antigens. B-cells act by stimulating the production of antibodies. T-cells contain receptors on their cell surfaces that are capable of recognizing and binding to specific antigens. Lymphocytes are found in the lymph nodes and spleen, and circulate continuously in the blood and lymph.


A hormone derived from serotonin and secreted by the pineal gland in inverse proportion to the amount of light received by the retina. Darkness perceived by the retina (or sleep) induces greater production which has been linked to the regulation of circadian rhythms and inducing sleep rhythms.


Of, pertaining to, or characteristic of menopause.


The period of permanent cessation of menstruation, usually occurring between the ages of 45 and 55.

Menstrual Cycle

A recurring cycle in which the endometrial lining of the uterus prepares for pregnancy; if pregnancy does not occur the lining is shed at menstruation. The average menstrual cycle is 28 days, day 1 being the beginning of bleeding.


The periodic discharge of blood and mucosal tissue from the uterus, occurring approximately monthly from puberty to menopause in non-pregnant women.

Metabolic Rate

The rate of metabolism; the amount of energy expended in a given period.


The sum of the physical and chemical processes in an organism, by which its material substance is produced, maintained and destroyed and by which energy is made available.


Substances necessary for taking part in a particular metabolic process, such as glucose in the metabolism of sugars and starches, and amino acids in the biosynthesis of proteins.


To reduce to particles that are only a few microns in diameter.

Midlife Crisis

A period of psychological stress occurring in middle age, thought to be triggered by a physical, occupational, or domestic event, such as menopause or andropause, diminution of physical prowess, job loss, or departure of children from the home.

Mobile Phlebotomy

A blood draw or venesection at a different location than the normal doctor’s office or laboratory; usually at a patient’s home.


A single very small particle, made up of atoms, which is indivisible.

Mood Swing(s)

An abrupt and apparently unaccountable change of mood.


Any of several chemical substances, such as epinephrine or acetylcholine, that transmit nerve impulses across a synapse to a postsynaptic element, such as another nerve, muscle or gland.

Night Sweat

Copious sweating during sleep. Night sweats may be an early indication of tuberculosis, AIDS, or other disease.

Nitric Oxide

Works as a signaling molecule in the cardiovascular system. Cells of a blood vessel’s inner walls use nitric oxide to signal the vessel to relax and dilate, increasing blood flow.

NorepinephrineNorepinephrine is an excitatory neurotransmitter that is important for attention and focus. Norepinephrine is synthesized from dopamine by means of the enzyme dopamine beta-hydroxylase, with oxygen, copper, and vitamin C as co-factors. Dopamine is synthesized in the cytoplasm, but norepinephrine is synthesized in the neurotransmitter storage vesicles.; Cells that use norepinephrine for formation of epinephrine use SAMe as a methyl group donor. Levels of epinephrine in the CNS are only about 10% of the levels of norepinephrine.

Obstructive Sleep Apnea

Sleep apnea that is caused by recurring interruption of breathing during sleep because of the obstruction of the upper airway by weak or malformed pharyngeal tissues, that occurs especially in obese middle-aged and elderly men, and that results in hypoxemia and chronic lethargy during the day. Also called obstructive sleep apnea syndrome.


Sold legally without a doctor’s prescription: over-the-counter drugs.


To produce and discharge eggs from an ovary or ovarian follicle.

Parkinson’s Disease

A degenerative disorder of the central nervous system characterized by tremor and impaired muscular coordination.

PEABeta-phenylethylamine (PEA) is an excitatory neurotransmitter derived from the amino acid phenylalanine.Studies have found that PEA promotes energy and elevates mood. PEA also functions as a synaptic neuromodulator inhibiting the reuptake of dopamine and norepinephrine. Studies have discovered that patients with depression have decreased PEA levels while increased levels have been found in patients with psychopathic symptoms. It has also been implicated in headaches and the antidepressant effects of exercise.; One of the biochemical abnormalities resulting from phenylketonuria, the absence of the enzyme that helps to synthesize phenylalanine into tyrosine, is an increased production of PEA. This can cause an elevated level of PEA in the urine. Since PEA is lipid soluble and readily crosses the blood-brain-barrier, the administration of PEA or of its precursor, phenylalanine, has been found to improve outcome with some antidepressants. Also, supplementation to manipulate PEA can help increase focus and attention.


The period around the onset of menopause that is often marked by various physical changes, such as hot flashes and menstrual irregularity. Also called peri-menopause, early menopause or pre-menopause.


The act or practice of opening a vein for letting blood as a therapeutic measure. Also called venesection.

PhytoestrogensSometimes called “dietary estrogens”, are a diverse group of naturally occurring non steroidal plant compounds that, because of their structural similarity with estradiol, have the ability to cause estrogenic or/and antiestrogenic effects.

Pituitary Gland

A gland at the base of the brain. The pituitary secretes several different hormones involved in key metabolic processes.

Post Menopause

All of the time in a woman’s life that take place after her last period ever, or more accurately, all of the time that follows the point when her ovaries become inactive. A woman who still has her uterus can be declared to be in post menopause once she has gone 12 full months with no flow at all, not even any spotting. Also seen as postmenopause or post-menopause.


A chemical that can be converted by the body into another is a precursor of the latter chemical.


An unsaturated hydroxyl steroid that is formed by the oxidation of steroids (like cholesterol) and yields progesterone on dehydrogenation.

Premenstrual Syndrome (PMS)

A varied group of physical and psychological symptoms, including abdominal bloating, breast tenderness, headache, fatigue, irritability, anxiety and depression that occur from 2 to 7 days before the onset of menstruation and cease shortly after menses begins.


A direction, usually written by the physician to the pharmacist for the preparation and use of a medicine or remedy.

Preventive Medicine

Measures taken to prevent illness or injury, rather than curing them. Preventive care may include examinations and screening tests tailored to an individual’s age, health and family history. Also called preventive care or preventative medicine.


A hormone that prepares the uterus for the fertilized ovum and maintains pregnancy.


A protein hormone produced by the pituitary gland of mammals that acts with other hormones to initiate the secretion of milk by the mammary glands. It also acts to maintain the corpus luteum of the ovary, which is the source of the female sex hormone progesterone. In males, high levels of prolactin can cause testosterone levels to decrease.

Prostate Specific Antigen (PSA)

A protein produced by the cells of the prostate gland. PSA is present in small quantities in the serum of normal men and is often elevated in the presence of prostate cancer and in other prostate disorders.


A molecular structure or site on the surface or interior of a cell that binds with substances such as hormones.

Reverse Triiodothyronine (Reverse T3)

A molecule which is an isomer of triiodothyroniine and derived from thyroxine through the use of deiodinase. Blocks the action of T3.


The act of injecting oneself with a drug or other substance.

SerotoninSerotonin is an inhibitory neurotransmitter synthesized by enzymes that act on tryptophan and/or 5-HTP. Serotonin is stored in presynaptic vesicles and released to transmit electrochemical signals across the synapse. Extensive research has been conducted surrounding serotonin and acts as a target for symptoms like low mood, compulsions, anxiousness, and headaches. Serotonin acts, in most cases, as an inhibitory neurotransmitter and, like GABA, modulates neuron voltage potentials to inhibit glutamate activity and neurotransmitter firing. Serotonin neurons have large numbers of axons and are important in integrating neural circuits. This also provides an explanation for serotonin’s role in so many health concerns.


An inhibitory neurotransmitter required for sleep.

Serotonin Metabolite5-Hydroxyindoleacetic acid (5-HIAA) is a major metabolite of serotonin, generated via a two step process, involving monoamine oxidase A (MAO-A) and aldehyde dehydrogenase. Measurement of 5-HIAA in combination with serotonin may offer insight into mechanisms underlying various clinical symptoms. The ratio of serotonin to 5-HIAA may be used to evaluate serotonin turnover and monoamine oxidase activity. Abnormal levels of 5-HIAA have been associated with depression, suicidal behaviors, aggression, chronic psychotropic medication use, and Parkinson’s Disease.


The clear yellowish fluid obtained upon separating whole blood into its solid and liquid components after it has been allowed to clot.

Sex Drive

A physiological need for sexual activity.

Sex Hormone

Any of a class of steroid hormones that regulate the growth and function of the reproductive organs or stimulate the development of the secondary sexual characteristics.

Sex Hormone-Binding Globulin (SHBG)

A glycoprotein produced by the liver cells that binds to sex hormones, specifically testosterone and estradiol.

Sleep Apnea

A temporary suspension of breathing occurring repeatedly during sleep that is caused especially by obstruction of the airway or a disturbance in the brain’s respiratory center and is associated especially with excessive daytime sleepiness.

Steroid Hormones

Any hormone containing the characteristic steroid ring complex; a term often associated with hormones such as progesterone, testosterone, estrogens, DHEA, and others.


Physical, mental, or emotional strain or tension; a specific response by the body to stimulus, as fear or pain, that disturbs or interferes with the normal physiological equilibrium of an organism.


An agent, condition or other stimulus that causes stress to an organism.


A subjective indication of a disorder reported by an afflicted person rather than being observed by an examiner.

Synthetic Hormones

Hormones made from plant progesterone and animal chemicals that are bio-similar but not identical to the hormones your body uses. Generally, an extra covalent bond or molecules are added so that it can be patented or to alter it’s chemical properties or clinical effects. Being non-identical to the body may cause significant harmful side effects.

TaurineTaurine is an inhibitory neurotransmitter involved in neuromodulatory and neuroprotective actions. Supplementing with taurine can have a specific effect on GABA function.There are two primary ways in which taurine affects GABA.; First, it can inhibit GABA transaminase, an enzyme that metabolizes GABA. This allows GABA to stay in the synaptic cleft longer to bind to the postsynaptic receptor. Second, taurine can bind to the GABAAreceptor mimicking the effects of GABA. By helping GABA function, taurine is an important neuromodulator for prevention of excitoxicity. Excitability occurs when glutamate binds to its receptor, in this case, the NMDA receptor. Once glutamate activates the NMDA receptor there is an increase in intracellular Ca++ causing depolarization or cell excitability. With glutamate release, there is also simultaneous GABA and taurine release. When the inhibitory neurotransmitters, GABA and taurine, activate the GABAA receptor, the result is an increase in intracellular Cl- ions. This results in hyperpolarization which reduces cell excitability. Thus, the overall effect of taurine supplementation is to support GABA function. The relevance of GABA support is to prevent overstimulation due to high levels of excitatory amino acids. Therefore, taurine and GABA constitute an important protective mechanism against excessive excitatory amino acids. Similarly, taurine is increased in response to the exposure of free radicals elucidating its neuroprotective actions. Exposure to free radicals increases glutamate excretion, further potentiation NMDA receptor activation. Taurine modulates this effect to prevent cell excitability by keeping the cell hyperpolarized. The supplementation of taurine can help alleviate some excitability issues associated with elevated excitatory amino acids as well as play a role in regulating the effect of free radicals.


A potent Androgenic hormone produced chiefly by the testes, which stimulates the development of male sex organs, secondary sexual traits and sperm.


The gland located in the center and anterior aspect of the neck responsible (amongst other things) for temperature regulation.

Thyroid Peroxidase (TPO)

An enzyme mainly expressed in the thyroid that liberates iodine for addition onto tyrosine residues on thyroglobulin for the production of T4, T3 and reverse T3.

Thyroid Stimulating Hormone (TSH)

A glycoprotein hormone secreted by the anterior portion of the pituitary gland that stimulates and regulates the activity of the thyroid gland. Also called thyrotropin.

Thyroxin (T4)

The thyroid gland iodine-containing hormone that regulates the metabolic rate of the body; used in the treatment of hypothyroidism.


A blood plasma protein for iron ion delivery.

Triodothyronine (T3)

A thyroid hormone derived from thyroxine but several times more potent; used in treating hypothyroidism

TyramineTyramine (4-hydroxy-phenethylamine) is a naturally occurring monoamine compound formed by the enzymatic decarboxylation of the aromatic amino acid tyrosine. The enzyme monoamine oxidase is responsible for the breakdown of tyramine. When this metabolic pathway is compromised by monoamine oxidase inhibitors (MAOIs), tyramine levels can become elevated and cause the release of neurotransmitters, such as dopamine, norepinephrine, and epinephrine, potentially leading to an increase in blood pressure. Dietary intake of tyramine has also been associated with cluster headaches and migraines, forcing many to restrict foods containing tyramine such as fish, chocolate, alcohol, and fermented foods including cheese, processed meat, and sauerkraut.

Urinary Incontinence

Any involuntary leakage of urine.

Vaginal Atrophy

Loss of muscle tension in the vagina.

Vaginal Dryness

The condition in which vaginal lubrication is insufficient causing increased friction and discomfort during sexual intercourse.

Vaginal Lubrication

The naturally produced lubricating fluid that reduces friction during sexual intercourse.


Substances or pollutants originating outside the body that have estrogen-like activities. Exposure to these substances can have a profound impact on a person’s natural hormonal balance.


Substances or pollutants originating outside the body that have hormone-like activities. Exposure to these substances can have a profound impact on a person’s natural hormonal balance.