Health & Medical Glossary
Plain-English explanations of medical terms, conditions, and concepts
A
Acne Vulgaris - Acne vulgaris is the medical name for ordinary acne - the most common skin condition in the world, affecting an estimate...
Adrenal Fatigue - Adrenal fatigue is a term used in alternative and integrative medicine to describe a collection of symptoms - including ...
AHA (Alpha Hydroxy Acid) - Alpha hydroxy acids, or AHAs, are a family of water-soluble exfoliating acids derived from natural sources. The most com...
Allergen - An allergen is any substance that triggers an abnormal immune response in a person who is sensitized to it, even though ...
Used in 1 article
Alopecia Areata - Alopecia areata is an autoimmune condition in which the immune system mistakenly attacks the body's own hair follicles, ...
Amino Acid - Amino acids are organic molecules that serve as the fundamental building blocks of proteins in your body. There are 20 s...
Used in 2 articles
Anagen Phase - Anagen is the active growth phase of the hair cycle. During anagen, cells in the hair bulb divide rapidly and push the h...
Androgenic Alopecia - Androgenic alopecia is the most common form of hair loss in both men and women. It is driven by a combination of genetic...
Anemia - Anemia is a condition in which your blood doesn't have enough healthy red blood cells or hemoglobin to carry adequate ox...
Used in 2 articles
Anti-inflammatory - Anti-inflammatory refers to any substance or treatment that reduces inflammation - the body's natural immune response to...
⭐ Used in 6 articles
Antibody - An antibody is a Y-shaped protein produced by specialized white blood cells called B lymphocytes (B cells) as part of th...
Antigen - An antigen is any molecule or molecular structure that can be recognized by the immune system and trigger an immune resp...
Aorta - The aorta is the largest artery in the human body, originating from the left ventricle of the heart and extending down t...
Arrhythmia - An arrhythmia is any abnormality in the timing or pattern of your heartbeat. Your heart normally beats in a regular, coo...
Used in 2 articles
Atherosclerosis - Atherosclerosis is a condition where fatty deposits called plaques build up inside the walls of your arteries - the bloo...
Used in 1 article
Autoimmune Response - An autoimmune response occurs when the immune system mistakenly identifies the body's own healthy cells and tissues as f...
Azelaic Acid - Azelaic acid is a dicarboxylic acid that is naturally produced by yeast on the skin and is also synthesized for medical ...
B
Benzoyl Peroxide - Benzoyl peroxide is an antimicrobial ingredient used for decades as a first-line treatment for inflammatory acne. When a...
Used in 1 article
BHA (Beta Hydroxy Acid) - Beta hydroxy acid - in cosmetic skincare almost always salicylic acid - is an oil-soluble exfoliating acid. That oil-sol...
Biomarker - A biomarker (short for biological marker) is a measurable indicator of a biological state or condition. Biomarkers can b...
Biotin - Biotin is a B vitamin (B7) that helps the body convert food into energy and is involved in the synthesis of keratin and ...
Blood Glucose - Blood glucose refers to the concentration of glucose (a simple sugar) circulating in your bloodstream. Glucose is your b...
⭐ Used in 3 articles
Blood Pressure - Blood pressure is the force exerted by circulating blood against the walls of your arteries as the heart pumps it throug...
⭐ Used in 10 articles
Blood-Brain Barrier - The blood-brain barrier (BBB) is a highly selective semi-permeable border of specialized cells that separates the circul...
Used in 2 articles
Blue Light Therapy (skincare) - Blue light therapy in skincare uses visible blue light - typically in the 415nm range - to target Cutibacterium acnes, t...
BMI - BMI (Body Mass Index) is a numerical value calculated from a person's weight and height that is used as a screening tool...
Brain Fog - Brain fog is a term used to describe a cluster of cognitive symptoms including difficulty concentrating, forgetfulness, ...
Used in 1 article
Broad Spectrum UV Protection - 'Broad spectrum' on a sunscreen label means the product has passed FDA testing for both UVA and UVB protection. This mat...
Bronchodilator - A bronchodilator is a type of medication that relaxes and widens (dilates) the airways (bronchi and bronchioles) in the ...
Used in 1 article
C
Cardiovascular - Cardiovascular refers to anything related to the heart (cardio) and blood vessels (vascular) - the circulatory system th...
⭐ Used in 14 articles
Catagen Phase - Catagen is the short transitional phase of the hair cycle that follows the growth phase (anagen). During catagen the hai...
Ceramides - Ceramides are a family of fatty molecules (lipids) that make up roughly half of the lipid 'mortar' that holds the cells ...
Used in 1 article
Chemical Peel - A chemical peel is an in-office (or, at lower strengths, at-home) treatment in which an acid solution is applied to the ...
Cholesterol - Cholesterol is a waxy, fat-like substance found in every cell of your body. Despite its bad reputation, cholesterol is e...
⭐ Used in 4 articles
Chronic Inflammation - Chronic inflammation is a prolonged, low-level inflammatory response that persists for weeks, months, or even years - un...
Used in 1 article
Circadian Rhythm - A circadian rhythm is a roughly 24-hour internal biological cycle that regulates many of your body's processes, includin...
Used in 2 articles
Cognitive Behavioral Therapy - Cognitive behavioral therapy (CBT) is a structured, evidence-based form of psychotherapy that focuses on identifying and...
⭐ Used in 4 articles
Collagen - Collagen is the most abundant protein in the human body, making up approximately 30% of all protein and serving as the p...
Used in 1 article
Comedone - A comedone is a plugged hair follicle and the building block of acne. It forms when dead skin cells, sebum, and sometime...
Cortisol - Cortisol is a steroid hormone produced by the adrenal glands (small glands sitting atop each kidney) that plays a centra...
⭐ Used in 10 articles
Cytokines - Cytokines are small proteins released by cells that act as chemical messengers of the immune system. They play a crucial...
⭐ Used in 4 articles
D
Dermal Papilla - The dermal papilla is a small cluster of specialized cells at the base of every hair follicle. It is the command center ...
Dermis - The dermis is the thick middle layer of your skin, sitting between the epidermis on top and the subcutaneous fat below. ...
Used in 1 article
Detoxification - Detoxification is the physiological process by which your body identifies, neutralizes, and eliminates harmful substance...
DHEA - DHEA (dehydroepiandrosterone) is a hormone produced primarily by the adrenal glands that serves as a precursor - a build...
DHT (Dihydrotestosterone) - Dihydrotestosterone (DHT) is an androgen hormone produced when the enzyme 5-alpha reductase converts testosterone into a...
DHT-Blocking Foods - A handful of foods contain compounds that weakly inhibit 5-alpha reductase, the enzyme that converts testosterone into D...
Dopamine - Dopamine is a neurotransmitter - a chemical messenger that transmits signals between nerve cells in the brain and throug...
⭐ Used in 6 articles
Dutasteride - Dutasteride is a 5-alpha reductase inhibitor closely related to finasteride but more potent: it blocks both Type I and T...
Dysbiosis - Dysbiosis refers to an imbalance in the composition or function of the microbial communities (microbiome) that live in a...
Used in 1 article
E
Ejection Fraction - Ejection fraction is a measurement of how well your heart pumps blood with each beat, expressed as a percentage. Specifi...
Electrolytes - Electrolytes are minerals that carry an electrical charge when dissolved in body fluids like blood, urine, and sweat. Th...
Endometriosis - Endometriosis is a chronic condition in which tissue similar to the lining of the uterus (the endometrium) grows outside...
Endorphins - Endorphins are a group of neurotransmitters produced naturally by the central nervous system and pituitary gland that ac...
Enzyme - An enzyme is a specialized protein that acts as a biological catalyst - it speeds up chemical reactions in the body with...
Used in 2 articles
Epidermis - The epidermis is the outermost layer of your skin - the part you can see and touch. It is remarkably thin (about as thic...
Epigenetics - Epigenetics is the study of changes in gene expression that occur without altering the underlying DNA sequence. While yo...
Estrogen - Estrogen is a group of steroid hormones that play central roles in the development and regulation of the female reproduc...
F
Facial Gua Sha - Gua sha is a traditional Chinese medicine technique in which a smooth-edged stone tool is used to apply firm strokes to ...
Fascia - Fascia is a thin, tough, web-like connective tissue that wraps around and connects every muscle, bone, organ, nerve, and...
Used in 1 article
Fibroblasts - Fibroblasts are the workhorse cells of the dermis. They manufacture collagen, elastin, and hyaluronic acid - the three s...
Finasteride - Finasteride is an FDA-approved oral medication for male pattern hair loss. It works by inhibiting Type II 5-alpha reduct...
Follicle Miniaturization - Follicle miniaturization is the gradual shrinking of hair follicles that drives androgenic alopecia. With each successiv...
FPHL (Female Pattern Hair Loss) - Female pattern hair loss is the most common form of hair loss in women, affecting up to 40% by age 50. It typically pres...
Free Radicals - Free radicals are unstable, highly reactive molecules that have one or more unpaired electrons in their outer shell. Thi...
FUE (Follicular Unit Extraction) - Follicular Unit Extraction, or FUE, is the more modern of the two main hair transplant techniques. Instead of removing a...
Functional Medicine - Functional medicine is a patient-centered, systems-based approach to healthcare that focuses on identifying and addressi...
FUT (Follicular Unit Transplantation) - Follicular Unit Transplantation, or FUT, is the older of the two main hair transplant techniques. In FUT, a strip of sca...
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