Browse 574 topics in Health conditions Welcome to the MedShun health library — a plain-language guide to more than 600 medical conditions, from the everyday to the rare, each explained clearly so you can understand what is happening and what to do next. Every entry is written to be read, not decoded. We set out what a condition is, why it happens, how it is diagnosed and how it is usually treated — in ordinary English, without the jargon that makes so much health information hard to follow. Not sure where to begin? You can browse the full list below, look up a condition by name, or start from a body area or symptom. Wherever you land, each explainer follows the same simple shape so you always know where to find the answer you need. How our health library is organised There are several ways in, so you can follow whichever suits the question you have arrived with: Browse A–Z Scan the full alphabetical list below to find a condition by name when you already know what you are looking for. Search by body area Start from the part of the body affected — heart, lungs, brain, skin and more — to narrow things down quickly. Explore by symptom Begin with what you are feeling and let our Symptom Checker point you toward conditions worth reading about. Plain-language explainers Every entry uses clear words, short sections and consistent headings, so the information is easy to follow. Explore by body area Many people find it easiest to start with the part of the body involved. Here are a few of the systems covered, with an example condition from each: For information only. This article is educational and is not a substitute for professional medical advice, diagnosis or treatment. Always talk to a qualified healthcare provider about your own symptoms and care. Test your knowledge Explore Health conditions Abdominal pain is any discomfort felt between the chest and the groin — the area most people simply call the “tummy” or “belly” — and it is one of the… Ablation is a medical procedure that deliberately destroys a small, targeted area of tissue — most often to correct an abnormal heart rhythm or to… Abortion is a medical procedure that ends a pregnancy, carried out either with medicines or through a short surgical procedure. Acetylcholine is one of the body’s most important chemical messengers, carrying signals from nerves to muscles and helping to steer memory, attention… Acinetobacter is a group of common environmental bacteria that rarely trouble healthy people, but can cause serious, hard-to-treat infections in those… Anterior cruciate ligament Tear An anterior cruciate ligament (ACL) tear is an injury to one of the main stabilising ligaments inside the knee, most often caused by a sudden twist… Acne is a very common skin condition in which tiny hair follicles become blocked by oil and dead skin cells, leading to spots and inflammation, most… Addiction is a treatable medical condition in which a person keeps using a substance or repeating a behaviour despite the harm it causes, because… An adenoidectomy is a common, minor operation to remove the adenoids — a small pad of tissue at the back of the nose — usually to help a child breathe… Attention deficit hyperactivity disorder Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental difference in how the brain manages attention, activity and impulses… Agoraphobia is an anxiety disorder in which everyday places or situations feel unsafe, leading a person to fear and avoid anywhere that escape might… Alcoholism is a long-term condition in which a person cannot control how much they drink, keeps drinking despite the harm it causes, and comes to… An allergy is an over-reaction of the immune system to a normally harmless substance — such as pollen, a food or an insect sting — that the body… Amyotrophic lateral sclerosis Amyotrophic lateral sclerosis (ALS) is a progressive condition in which the nerve cells that control voluntary movement gradually break down, so the… Alternative Health Alternative health covers a broad range of therapies and practices — from acupuncture and herbal remedies to meditation and massage — that sit… Alzheimer's Disease Alzheimer’s disease is a progressive brain condition in which nerve cells are gradually damaged and lost, slowly eroding memory, thinking and the… Amenorrhea is the absence of menstrual periods — either periods that never started by the expected age, or regular periods that have stopped for three… Amino acids are the small building blocks that join together to make proteins — the molecules your body uses to build muscle, repair tissue, carry… Amyloidosis is a rare group of conditions in which an abnormal protein called amyloid builds up in organs and tissues, gradually stopping them from… Anal cancer is an uncommon cancer in which abnormal cells grow in the tissues of the anus — the short passage at the end of the bowel through which… Anaphylaxis is a severe, whole-body allergic reaction that comes on quickly and can be life-threatening, needing emergency treatment with adrenaline… Anatomy is the study of how the body is built — the organs, bones, muscles and tissues that fit together to keep you alive and moving. Anaemia is a common condition in which the blood cannot carry enough oxygen around the body, usually because there are too few healthy red blood cells… Anaesthesia is the use of medicines to block pain and, in some cases, awareness during surgery, tests or other procedures — so treatment can be… An aneurysm is a bulge that forms in the wall of a blood vessel when a weakened section stretches and balloons outwards under the pressure of the… Angina is chest pain or discomfort that happens when the heart muscle does not get enough oxygen-rich blood, usually because the arteries supplying… Angioplasty is a common, minimally invasive procedure that widens a narrowed or blocked blood vessel — most often a coronary artery supplying the… Ankylosing Spondylitis Ankylosing spondylitis is a long-term inflammatory condition that mainly affects the spine and the joints where it meets the pelvis, causing pain and… Anorexia nervosa is a serious mental health condition in which a person limits how much they eat and becomes intensely preoccupied with their body… Anthrax is a serious but rare infection caused by the bacterium Bacillus anthracis , which usually spreads to people from infected animals or their… Antiphospholipid Syndrome Antiphospholipid syndrome is an autoimmune condition in which the immune system makes antibodies that make the blood far more likely to clot, causing… Antisocial Personality Disorder Antisocial personality disorder is a long-term mental health condition in which a person finds it hard to feel empathy, respect boundaries or consider… Anxiety Disorders Anxiety disorders are common mental-health conditions in which worry or fear becomes frequent, intense and hard to control, and starts to interfere… Aortic Stenosis Aortic stenosis is a common heart-valve problem in which the aortic valve stiffens and narrows, so the heart has to work harder to push blood out to… Aplastic anemia Aplastic anaemia is a rare and serious condition in which the bone marrow stops making enough new blood cells, leaving the body short of red cells… Appendicitis is a painful swelling of the appendix, a small pouch attached to the large intestine, and it usually needs urgent treatment to stop the… Arm pain is any discomfort, ache or soreness felt anywhere from the shoulder to the fingers, and it is one of the most common everyday complaints. An arrhythmia is a problem with the rate or rhythm of the heartbeat, so the heart beats too fast, too slowly or in an irregular pattern. Arthritis is a common condition that causes pain, stiffness and swelling in one or more joints. It is not a single disease but a broad term covering… Arthroscopy is a keyhole procedure that lets a surgeon look inside a joint — and often treat the problem in the same sitting — through a few small… Autonomous sensory meridian response Autonomous sensory meridian response (ASMR) is a pleasant, tingling sensation that spreads across the scalp, neck and spine in response to gentle… Asperger’s syndrome is a lifelong developmental difference, now understood as part of the autism spectrum, that shapes how a person communicates… Aspergillus is a common group of moulds found almost everywhere in the environment — usually harmless, but capable of causing a range of illnesses… Aspiration Pneumonia Aspiration pneumonia is a lung infection that develops after food, drink, saliva, stomach contents or other material is breathed into the airways… Asthma is a common long-term condition in which the airways of the lungs become inflamed and over-sensitive, narrowing in response to triggers and… Atherosclerosis Atherosclerosis is a long-term condition in which fatty deposits and other material build up inside the walls of the arteries, gradually stiffening… Athlete’s foot is a common fungal skin infection of the feet — usually starting between the toes — that causes an itchy, flaky, sometimes sore rash. Atrial Fibrillation Atrial fibrillation is the most common heart-rhythm disorder, in which the heart’s upper chambers beat in a fast, chaotic and irregular way instead of… Autism, or autism spectrum disorder, is a lifelong developmental difference that shapes how a person communicates, relates to other people and… Autoimmune Diseases Autoimmune diseases are long-term conditions in which the immune system mistakes part of the body for a threat and attacks its own healthy tissue… Back pain is discomfort anywhere along the spine — from a dull ache to a sharp, shooting sensation — and it is one of the most common reasons people… Bacterial Vaginosis Bacterial vaginosis is a very common condition in which the natural balance of bacteria in the vagina is disturbed, leading to a change in discharge… Barrett's Esophagus Barrett’s Esophagus is a condition in which years of acid reflux change the cells lining the lower food pipe, replacing them with a type more like the… The beauty toolbox is the small collection of everyday products, tools and habits people use to care for their skin, hair and nails — simple self-care… Bedbugs are small, wingless insects that feed on human blood at night, leaving behind itchy bites and, for many people, a good deal of worry — but… Bedwetting is the unintended passing of urine during sleep — very common in young children and, less often, a problem that continues into older… Benign Prostatic Hyperplasia Benign prostatic hyperplasia is a common, non-cancerous enlargement of the prostate gland that squeezes the urethra and makes passing urine harder as… Binge Eating Disorder Binge eating disorder is a common eating disorder in which a person regularly eats very large amounts of food in a short time while feeling a loss of… A biopsy is a procedure in which a small sample of tissue is removed from the body so it can be examined under a microscope, most often to find out… Bipolar Disorder Bipolar disorder is a long-term mental health condition in which mood swings far beyond the everyday ups and downs, shifting between emotional highs… Bird flu, or avian influenza, is an infection caused by influenza type A viruses that mainly spread among birds but can occasionally pass to people… Black health is about the everyday steps and specialist knowledge that help people of African, Caribbean and Black diaspora heritage stay well — and… Bladder cancer is a growth of abnormal cells in the lining of the bladder — the muscular sac that stores urine — most often signalled by blood in the… Blepharoplasty is surgery to remove or reshape excess skin, muscle and fat around the eyelids, done to improve vision, comfort or appearance. Blindness is the partial or complete loss of sight that cannot be corrected with glasses or contact lenses, ranging from severely reduced vision to a… A blood clot is a gel-like clump of blood that forms inside a vein or artery, and it becomes dangerous when it blocks the flow of blood to a vital… Blood Disorders Blood disorders are conditions that affect the cells and fluid of the blood — the red cells, white cells, platelets or plasma — changing how well the… Blood in the urine — known medically as haematuria — means red blood cells are appearing in the urine, sometimes enough to change its colour and… Blood transfusion A blood transfusion is a common, safe procedure in which donated blood — or one of its parts — is given through a vein to replace what the body has… Body image is the mental picture you hold of your own body — how you see it, what you believe about it, and how you feel living inside it. Bone cancer is a rare condition in which abnormal cells grow out of control inside a bone, forming a tumour that can weaken the bone and, if… A bone fracture is a break in the continuity of a bone, ranging from a fine crack to a complete snap, usually caused by a force greater than the bone… Borderline Personality Disorder Borderline personality disorder (BPD) is a mental health condition in which emotions feel unusually intense and hard to manage, affecting how a person… Botulism is a rare but serious illness in which a powerful nerve toxin blocks the signals between nerves and muscles, causing weakness and paralysis… Brain cancer is the growth of a malignant tumour within the brain — a mass of abnormal cells that multiplies out of control and can press on or invade… A brain tumour is a growth of abnormal cells in or around the brain, which can be non-cancerous (benign) or cancerous (malignant) and may press on… Breast cancer is a disease in which cells in the breast begin to grow out of control, forming a lump or thickening that can, if left untreated, spread… Breast pain, also called mastalgia, is discomfort, tenderness or a heavy aching feeling in one or both breasts — and in most cases it is not a sign of… Breathing Difficulty Breathing difficulty — often called breathlessness or shortness of breath — is the uncomfortable feeling that you cannot get enough air or that… Breech birth is when a baby is positioned bottom-first or feet-first in the womb near the end of pregnancy, rather than in the usual head-down… Bronchitis is inflammation of the bronchi — the main airways that carry air into the lungs — causing a cough that often brings up mucus. Brucellosis is a bacterial infection caught from animals or unpasteurised dairy, causing waves of fever, drenching sweats and aching joints that can… Bubonic plague is a serious bacterial infection, spread mainly by the bite of an infected flea, that causes painfully swollen lymph glands and… Bug bites and stings are small wounds left when an insect or other tiny creature pierces the skin to feed or defend itself, usually causing brief… Bulimia nervosa is an eating disorder in which a person has episodes of feeling out of control around food, followed by behaviour meant to undo what… A bunion is a bony bump that forms on the joint at the base of the big toe, when the toe drifts inwards and the joint gradually pushes outwards. Burnout is a state of deep physical, emotional and mental exhaustion brought on by long-term, unrelenting stress — most often from work or caring for… Cesarean section A caesarean section is an operation to deliver a baby through a cut made in the mother’s tummy and womb, rather than through a vaginal birth. Clostridioides difficile Clostridioides difficile, often shortened to C. diff, is a bacterium that can cause severe diarrhoea and inflammation of the bowel, usually after… A calorie is a unit of energy — a measure of how much fuel a food gives your body, and how much energy your body uses to move, think and stay alive. Campylobacter is a common bacterium that causes food poisoning, most often after eating undercooked poultry or drinking unpasteurised milk. Cancer is a group of diseases in which the body’s own cells begin to grow and divide out of control, forming growths that can invade nearby tissue and… A canker sore is a small, painful ulcer that forms on the soft lining inside the mouth — and, although it can be sore for a few days, it is harmless… Carbohydrates are the body’s main source of everyday energy — the sugars, starches and fibre found in foods such as bread, rice, fruit, vegetables and… Carpal tunnel syndrome is a common condition in which a nerve at the wrist becomes squeezed, causing tingling, numbness and pain in the hand and… Cataplexy is a sudden, brief loss of muscle control triggered by strong emotion — often laughter — while the person stays fully awake and aware. A cataract is a clouding of the normally clear lens inside the eye, which scatters light and gradually blurs and dims vision. Catecholamines are a family of “fight-or-flight” chemicals — chiefly adrenaline, noradrenaline and dopamine — that the body releases to gear you up… Catheterization Catheterization is a common medical procedure in which a thin, flexible tube called a catheter is guided into the body — most often into the bladder… Celiac disease is a lifelong autoimmune condition in which eating gluten — a protein found in wheat, barley and rye — makes the immune system attack… Cellulitis is a common bacterial infection of the deeper layers of the skin and the soft tissue beneath it, causing an area of skin to become red… Cerebral palsy is a lifelong condition that affects movement, posture and co-ordination, caused by a problem with the developing brain before, during… Cervical Cancer Cervical cancer is a cancer that begins in the cells of the cervix — the lower part of the womb that opens into the vagina — and is nearly always… Chagas disease is a parasitic infection caused by Trypanosoma cruzi , spread mainly by blood-sucking triatomine insects, which can quietly damage the… A chalazion is a small, usually painless lump in the eyelid that forms when one of the tiny oil glands along the lid becomes blocked. Chapped lips are lips that have become dry, cracked and sore, usually because the delicate skin has lost more moisture than it can hold on to. Chemical Pregnancy A chemical pregnancy is a very early miscarriage that happens shortly after implantation — usually within the first few weeks — often before a scan… Chemotherapy is a cancer treatment that uses powerful medicines to destroy fast-growing cancer cells or slow their spread throughout the body. Chickenpox is a common, usually mild childhood infection caused by the varicella-zoster virus, which brings on an itchy, spotty rash alongside a fever… Chikungunya is a viral infection spread by mosquito bites that causes sudden fever and severe joint pain, which can occasionally linger for months… Chlamydia is one of the most common sexually transmitted infections, caused by bacteria that are passed on during unprotected sex — often with no… Cholera is an acute diarrhoeal infection caused by the bacterium Vibrio cholerae , usually caught from water or food contaminated with faeces, which… Chondromalacia is a condition in which the smooth cartilage on the underside of the kneecap softens and wears down, causing pain around the front of… Chronic Fatigue Syndrome Chronic fatigue syndrome (ME/CFS) is a serious, long-term illness that affects the whole body, causing profound fatigue and a range of symptoms that… Chronic pain is pain that lasts for more than three months — continuing beyond the time an injury or illness would normally take to heal, and… Circumcision is a surgical procedure to remove the foreskin — the fold of skin that covers the head of the penis. Colds and flu are common infections of the nose, throat and airways caused by viruses — the cold is usually mild, while flu tends to come on faster… Cold sores are small, fluid-filled blisters that appear on or around the lips, caused by the herpes simplex virus and usually clearing on their own… A colectomy is an operation to remove all or part of the colon — the large intestine — usually to treat disease, blockage or cancer of the bowel. College health is about looking after your body and mind during the busy, often unpredictable years of student life — from eating and sleeping well to… Colon cancer is a cancer that begins in the large bowel (colon), most often growing slowly from a small non-cancerous growth called a polyp over many… A colonoscopy is a test that lets a doctor look directly at the lining of your large bowel using a thin, flexible camera, to check for and treat… Color Blindness Colour blindness is a common, usually inherited condition in which the eye struggles to tell certain colours apart — most often reds and greens. A colposcopy is a close-up examination of the cervix, vagina and vulva using a lighted magnifying instrument, usually carried out after an abnormal… The common cold is a mild viral infection of the nose and throat. It is one of the most frequent illnesses there is, and while it can leave you… A concussion is a mild traumatic brain injury caused by a bump, blow or jolt to the head that briefly disturbs the way the brain works. Constipation means passing stools less often than usual, or finding them hard, dry and difficult to move — a very common problem that is rarely… Chronic Obstructive Pulmonary Disease Chronic obstructive pulmonary disease (COPD) is a common long-term lung condition in which the airways become narrowed and the air sacs damaged, so it… An umbilical cord knot is a loop in the baby’s cord that tightens into a knot as the baby moves in the womb — most are loose, cause no harm, and are… Coronary Heart Disease Coronary heart disease is a common long-term condition in which the arteries that supply the heart muscle become narrowed by a build-up of fatty… Coronaviruses are a large family of common viruses that infect the nose, throat and lungs — most cause mild colds, but a few, including the virus… Cortisol is the body’s main stress hormone — a steroid released by the adrenal glands that helps you wake up, respond to pressure, and keep energy… A cough is a sudden, forceful release of air from the lungs — the body’s natural way of clearing the throat and airways of mucus, dust or anything… Carbapenem-resistant Enterobacterales Carbapenem-resistant Enterobacterales (CRE) are a group of gut bacteria that have become resistant to carbapenems — powerful antibiotics usually kept… Crohn's Disease Crohn’s disease is a long-term condition in which parts of the digestive tract become inflamed, causing tummy pain, diarrhoea and other symptoms that… Computerized Tomography Scan A computerized tomography (CT) scan is a painless imaging test that uses X-rays and a computer to build detailed cross-sectional pictures of the… Cyanobacteria, often called blue-green algae, are tiny water-living microbes that can multiply into dense “blooms” and sometimes release toxins that… Cystic Fibrosis Cystic fibrosis is an inherited condition in which a faulty gene makes the mucus in the lungs and digestive system thick and sticky, so it clogs the… Cystitis is inflammation of the bladder, most often caused by a urinary tract infection, that makes passing urine frequent, urgent and uncomfortable. A cystoscopy is a procedure that lets a doctor look inside your bladder and urethra using a thin tube with a camera on the end, called a cystoscope. Dandruff is a very common, harmless scalp condition in which flakes of dead skin shed faster than usual, often with mild itching but no lasting damage… Ductal carcinoma in situ Ductal carcinoma in situ (DCIS) is the earliest, non-invasive form of breast cancer, in which abnormal cells are contained inside the milk ducts and… Dehydration happens when your body loses more fluid than it takes in, leaving it without enough water to work normally. Dementia is not a single illness but a group of symptoms — caused by different diseases that damage the brain — leading to a gradual decline in… Dengue fever is a viral infection spread by mosquito bites that causes a high temperature, severe aches and, in a small number of people, a dangerous… Dental health is the day-to-day care of your teeth, gums and mouth — keeping them clean, strong and free of disease so you can eat, speak and smile… Depression is a common mental-health condition in which low mood and a loss of interest or pleasure persist for weeks or longer, affecting how you… Dermatology 101 Dermatology is the branch of medicine devoted to the skin, hair and nails — and this plain-language primer covers how your skin works, the problems… Deviated Septum A deviated septum is when the thin wall of bone and cartilage that divides the inside of your nose sits off-centre, making one nasal passage narrower… Diabetes is a common long-term condition in which the level of sugar (glucose) in the blood becomes too high because the body cannot make enough… Diabetic Macular Edema Diabetic macular edema is a build-up of fluid in the macula — the central part of the retina — caused by diabetes damaging the tiny blood vessels at… Diabetic Retinopathy Diabetic retinopathy is a complication of diabetes in which persistently high blood sugar damages the tiny blood vessels of the retina — the… Diarrhea means passing loose or watery stools more often than usual — a common, usually short-lived sign that something is irritating or upsetting the… Diet and Nutrition Diet and nutrition is about the food and drink you take in and how your body uses it — the day-to-day fuel that shapes your energy, growth, mood and… Digestive Health Digestive health is how well your gut breaks down food, absorbs the nutrients you need, and moves the rest along comfortably — from the first bite to… Dilation & Curettage Dilation and curettage, usually shortened to D&C, is a short gynaecological procedure in which the neck of the womb is gently opened and the lining of… Diverticulitis is a common digestive condition in which one or more of the small pouches that can form in the wall of the large intestine become… Dopamine is a chemical messenger made in the brain and body that shapes how you feel motivation, pleasure and reward, and helps control movement… Down syndrome is a lifelong genetic condition in which a person is born with an extra copy of chromosome 21, which gently changes the way the body and… Dravet Syndrome Dravet syndrome is a rare, lifelong form of epilepsy that begins in the first year of life, in which a change in a single gene leaves the developing… Drug addiction is a treatable health condition in which a person keeps using a substance even when it is causing harm, because changes in the brain… Drugs and Supplements “Drugs and supplements” covers everything from prescription medicines and pharmacy remedies to vitamins, minerals and herbal products — substances… Dry eye is a common condition in which the eyes do not make enough tears, or the tears evaporate too quickly, leaving the surface of the eye poorly… Dupuytren's Contracture Dupuytren’s contracture is a slow, painless thickening of the tissue just beneath the skin of the palm that gradually pulls one or more fingers… Dyshidrosis is a type of eczema in which small, intensely itchy blisters break out on the palms of the hands, the sides of the fingers and sometimes… Dyslexia is a common, lifelong difference in the way the brain processes written language, mainly affecting the accuracy and speed of reading… Escherichia coli Escherichia coli, usually shortened to E. coli, is a common bacterium that lives harmlessly in the gut of people and animals — but a few strains can… An ear infection is an infection of the ear — most often the middle ear, just behind the eardrum — where fluid and inflammation build up and cause… Ear pain, or earache, is discomfort felt in or around the ear that can range from a dull ache to a sharp, stabbing or burning sensation. Ear, Nose & Throat The ear, nose and throat are three closely linked parts of the head and neck that let you hear, breathe, smell, taste and speak — and the medical… Eating Disorders Eating disorders are mental-health conditions in which a person’s relationship with food, eating and body image becomes a way of coping with difficult… Ebola virus disease is a rare but serious illness caused by infection with an ebolavirus, spread through contact with the blood or body fluids of an… An echocardiogram is a painless ultrasound scan of the heart that uses sound waves to build a moving picture of its chambers, valves and pumping… Ectopic Pregnancy An ectopic pregnancy is one that develops outside the womb — most often in a fallopian tube — where a pregnancy cannot grow safely and which can put a… Eczema is a common long-term condition in which the skin becomes dry, itchy and inflamed, flaring up from time to time and settling in between. The… Emotional Health Emotional health is your ability to understand your feelings, cope with life’s ups and downs, and stay connected to yourself and the people around… Endocarditis is a serious infection of the endocardium — the smooth inner lining of the heart — that most often settles on one of the heart valves and… Endometriosis is a common long-term condition in which tissue similar to the lining of the womb grows in other parts of the body, where it bleeds and… Endorphins are the body’s own natural painkillers — chemical messengers released by the nervous system that ease discomfort and lift your mood… An endoscopy is a procedure that lets a doctor look inside your body using a thin, flexible tube with a tiny camera and light on the end, called an… Enteroviruses are a large family of very common viruses that usually cause mild, cold-like illness but can occasionally lead to more serious… Epididymitis is inflammation of the epididymis — the coiled tube behind each testicle that stores and carries sperm — usually caused by a bacterial… Epilepsy is a common long-term brain condition in which bursts of abnormal electrical activity cause repeated seizures — sudden, temporary changes in… Epinephrine — better known as adrenaline — is the body’s emergency hormone, released in an instant to power the “fight-or-flight” response and, as a… An episiotomy is a small, planned surgical cut made in the area between the vagina and the anus during childbirth, used to enlarge the opening and… Erectile Dysfunction Erectile dysfunction is the ongoing difficulty getting or keeping an erection firm enough for satisfying sex. Esophageal Cancer Oesophageal cancer is a cancer that begins in the oesophagus — the muscular tube that carries food and drink from the throat down to the stomach. Esophagitis is inflammation of the lining of the oesophagus — the muscular tube that carries food and drink from the throat down to the stomach. Estrogen is the main group of female sex hormones, guiding the reproductive system while also shaping bone strength, mood, skin and heart health… Excessive gas is passing wind or belching much more often than usual, or feeling uncomfortably bloated by trapped air in the stomach and bowel. Exocrine Pancreatic Insufficiency Exocrine pancreatic insufficiency (EPI) is a condition in which the pancreas does not make enough digestive enzymes, so the body cannot break down and… Fecal Impaction Fecal impaction is a large, hardened mass of stool that becomes stuck in the rectum or lower bowel and can no longer be passed normally. “Feed your skin” is the simple idea that what you eat helps shape how your skin looks and feels — a balanced, colourful diet gives skin the building… Fertility is the natural ability to conceive a child — a result of many parts of the body, hormones and timing working together in both partners. Fibromyalgia is a long-term condition that causes widespread pain and tenderness across the body, together with fatigue, poor sleep and problems with… Fifth disease is a common, usually mild viral infection of childhood that produces a bright red “slapped-cheek” rash on the face followed by a lacy… Flu, or influenza, is a common viral infection of the nose, throat and lungs that tends to come on suddenly and can leave you feeling far more unwell… Functional magnetic resonance imaging Functional magnetic resonance imaging (fMRI) is a scan that maps brain activity by tracking tiny changes in blood flow, showing which parts of the… Follicle-Stimulating Hormone Follicle-stimulating hormone (FSH) is a reproductive hormone that helps control fertility — guiding the growth of egg-containing follicles in the… Foot health is about keeping the bones, joints, skin and nerves of your feet working well, so you can stand, walk and stay active comfortably… Frozen Shoulder Frozen shoulder is a common condition in which the shoulder becomes painful and progressively stiff, so that moving the arm freely becomes difficult… Gamma-Aminobutyric Acid Gamma-aminobutyric acid, better known as GABA, is the brain’s main “calming” chemical messenger — the signal that dials nerve activity down and keeps… The gallbladder is a small, pear-shaped organ tucked under the liver that stores and concentrates bile, the fluid your body uses to break down fatty… Gastritis is inflammation of the lining of the stomach, which can come on suddenly or build up slowly and often causes pain or discomfort in the upper… Gastroenteritis Gastroenteritis is a short-lived infection that inflames the stomach and intestines, causing diarrhoea and vomiting as the gut works to clear it. Generalized Anxiety Disorder Generalized anxiety disorder (GAD) is a common mental-health condition in which worry becomes excessive, hard to control and present on most days… Genetic Diseases Genetic diseases are health conditions caused by changes in a person’s DNA — the set of instructions that tells the body how to grow, develop and… Genital warts are small growths or bumps on the genital or anal area caused by the human papillomavirus (HPV), and they are one of the most common… Gastroesophageal reflux disease Gastro-oesophageal reflux disease (GORD, spelt GERD in the United States) is a common long-term condition in which acid from the stomach repeatedly… Gestational Diabetes Gestational diabetes is a type of raised blood sugar that develops during pregnancy and, in most women, clears up soon after the baby is born. Gingivitis is a common, early form of gum disease in which the gums become inflamed, red and swollen, and bleed easily — most often because of a… Glaucoma is a group of eye conditions in which the optic nerve becomes damaged, usually because pressure inside the eye is too high, and which can… Glucocorticoids Glucocorticoids are a group of powerful anti-inflammatory medicines — often simply called “steroids” — used to calm inflammation and quieten an… Glutamate is the brain’s most abundant “go” signal — the main excitatory neurotransmitter that switches nerve cells on and underpins learning, memory… Gluten is a family of proteins found in wheat, barley and rye that gives bread its stretch and chew — harmless for most people, but a genuine problem… Gonorrhea is a common sexually transmitted infection caused by bacteria, spread through unprotected sex, that can affect the genitals, rectum, throat… Gout is a common form of arthritis in which needle-sharp crystals of uric acid build up inside a joint, causing sudden attacks of intense pain… Gratitude is the simple practice of noticing and appreciating the good things in your life — and, done regularly, it can measurably lift your mood… Graves' Disease Graves’ disease is an autoimmune condition in which the immune system stimulates the thyroid gland to make too much thyroid hormone, speeding up the… Green health is the idea that regular contact with nature — parks, gardens, woodland, water and even indoor plants — measurably supports our physical… Grief is the natural response to loss — most often the death of someone we love — and it can affect how we feel, think, behave and even how our body… Guillain-Barre Syndrome Guillain-Barré syndrome is a rare but serious condition in which the body’s own immune system attacks the peripheral nerves, causing muscle weakness… A gynecologist is a doctor who specialises in the health of the female reproductive system — caring for the vagina, uterus, ovaries and breasts… Helicobacter pylori Helicobacter pylori (often shortened to H. pylori ) is a common spiral-shaped bacterium that lives in the lining of the stomach and can cause… Hair loss is a reduction in the amount of hair on the scalp or body — ranging from gradual thinning to sudden patchy shedding — and it is one of the… Hammer toe is a deformity in which one of the smaller toes bends downwards at its middle joint, so the toe curls into a claw-like or hammer shape… Hashimoto's Thyroiditis Hashimoto’s thyroiditis is a long-term autoimmune condition in which the immune system gradually attacks the thyroid gland, so it slowly makes less… A headache is pain or discomfort felt in the head or upper neck — one of the most common health complaints and, in the great majority of cases… Headache and Migraine Headaches are one of the most common health complaints, ranging from a mild, passing ache to the intense, disabling attacks of migraine. Most are not… Healthcare Reform Healthcare reform is the effort to change how a country pays for, organises and delivers medical care — with the aim of making it more affordable… A healthy home is a living space set up to protect the people in it — with clean air, safe water, good light, comfortable temperatures and few hidden… Healthy Recipes Healthy recipes turn everyday nutrition advice into real meals — balanced, satisfying dishes that protect long-term health without asking you to give… Healthy skin is your body’s largest organ working quietly in the background — a living barrier that protects you, senses the world, and reflects your… Healthy travel is about planning ahead so that a trip abroad — or a long journey closer to home — leaves you with good memories rather than an… A heart attack is a medical emergency in which the blood supply to part of the heart muscle is suddenly blocked, starving it of oxygen and causing… Heart disease is a group of conditions that affect the heart and blood vessels, most often when the arteries supplying the heart become narrowed or… Heart failure is a long-term condition in which the heart cannot pump blood around the body as well as it should, so oxygen and nutrients are not… Heavy Metal Poisoning Heavy metal poisoning is the harm caused when toxic metals such as lead, mercury, arsenic or cadmium build up in the body, disrupting the way cells… Hemochromatosis Hemochromatosis is a condition in which the body absorbs and stores too much iron, which slowly builds up in organs such as the liver, heart and… Hemodialysis is a treatment that filters waste, extra salts and excess fluid from the blood when the kidneys can no longer do the job well enough on… Haemophilia is a rare inherited condition in which the blood does not clot properly, so bleeding after an injury lasts longer than usual and can… Hemorrhoidectomy A hemorrhoidectomy is a surgical operation to remove large or troublesome hemorrhoids — swollen blood vessels around the anus and lower rectum — when… Haemorrhoids — often called piles — are swollen blood vessels in and around the back passage (anus and lower rectum) that can bleed, itch or become… Hepatitis means inflammation of the liver — most often caused by a viral infection, but sometimes by alcohol, certain medicines or the body attacking… Hepatitis A is a short-term liver infection caused by a virus that is spread mainly through food or water contaminated with tiny traces of infected… Hepatitis B is a liver infection caused by the hepatitis B virus, which can range from a short-lived illness to a long-term (chronic) condition that… Hepatitis C is a viral infection of the liver, spread through blood-to-blood contact, that can quietly cause long-term liver damage — but is now… Hepatitis D is a viral infection of the liver caused by the hepatitis delta virus, which can only take hold in people who also have hepatitis B. Hepatitis E is a liver infection caused by the hepatitis E virus, usually spread through contaminated water or undercooked meat and, in most people… Hereditary Angioedema Hereditary angioedema is a rare inherited condition that causes recurring episodes of severe swelling deep in the skin and the lining of the airways… A hernia happens when an internal part of the body, most often a loop of bowel or fatty tissue, pushes through a weak spot in the surrounding muscle… Herpes is a very common, lifelong viral infection caused by the herpes simplex virus (HSV), which produces occasional outbreaks of small blisters or… A hiatal hernia happens when part of the stomach pushes up through the diaphragm into the chest, often allowing stomach acid to rise back into the… Hidradenitis Suppurativa Hidradenitis suppurativa is a long-term skin condition that causes painful lumps, abscesses and scarring, usually in areas where skin rubs together. High Cholesterol High cholesterol means there is too much of a fatty substance called cholesterol in the blood, which over time can build up in the artery walls and… High-Fructose Corn Syrup High-fructose corn syrup (HFCS) is a liquid sweetener made from corn starch that is widely used to sweeten fizzy drinks, packaged foods and many… Hip pain is discomfort felt in or around the hip joint, groin, buttock or outer thigh — a very common problem that can come from the joint itself or… Hip replacement A hip replacement is an operation to remove a worn or damaged hip joint and replace it with an artificial one, easing pain and helping you move more… Histamine is a natural chemical made by the body that helps fight off invaders, signals between nerve cells and controls the release of stomach acid —… HIV is a virus that gradually weakens the immune system, but with today’s treatment it is a manageable long-term condition — and people who are on… Hives, also called urticaria, is a common skin reaction in which raised, itchy welts appear suddenly when the body releases a natural chemical called… Hodgkin Lymphoma Hodgkin lymphoma is a cancer of the lymphatic system in which white blood cells called lymphocytes grow out of control, most often causing painless… Homozygous Familial Hypercholesterolemia Homozygous familial hypercholesterolemia (HoFH) is a rare inherited condition in which the body cannot clear “bad” LDL cholesterol from the blood… Hormones are the body’s chemical messengers — substances made by glands and carried in the blood to control everything from growth and mood to hunger… Human papillomavirus Human papillomavirus (HPV) is an extremely common group of viruses that infect the skin and moist linings of the body — most people catch it at some… Hyperemesis Gravidarum Hyperemesis gravidarum is a serious pregnancy condition that causes relentless, severe nausea and vomiting — far beyond ordinary morning sickness —… Hyperhidrosis is a common condition in which the body sweats far more than it needs to cool itself, often soaking the hands, feet, underarms or face… Hyperkalemia is a condition in which the level of potassium in the blood rises above the normal range, which can interfere with the way nerves and… Hyperopia, or farsightedness, is a common focusing problem in which distant objects are seen more easily than close ones, because light entering the… High blood pressure, or hypertension, is a very common long-term condition in which the force of blood pushing against the walls of your arteries… Hyperthyroidism Hyperthyroidism is a condition in which the thyroid gland becomes overactive and makes too much thyroid hormone, speeding up many of the body’s… Hypoglycaemia is an unusually low level of glucose (sugar) in the blood — the body’s main fuel — which can leave you feeling shaky, sweaty and… Hypophosphatasia Hypophosphatasia is a rare inherited condition in which a faulty gene lowers an enzyme the body needs to harden bones and teeth, leaving them soft… Hypothyroidism, or an underactive thyroid, is a common long-term condition in which the thyroid gland makes too little thyroid hormone, gradually… A hysterectomy is an operation to remove the womb (uterus), most often carried out to relieve conditions that cause heavy bleeding, pain or the growth… A hysteroscopy is a procedure that lets a doctor look inside the womb (uterus) using a slim, lighted telescope passed gently through the vagina and… Inflammatory bowel disease Inflammatory bowel disease (IBD) is a group of long-term conditions in which the lining of the digestive tract becomes inflamed, causing tummy pain… Irritable bowel syndrome Irritable bowel syndrome (IBS) is a common, long-term condition that affects how the gut works, causing tummy pain, bloating and changes in bowel… An ileostomy is an operation that brings the end of the small intestine out through an opening in the abdomen, so that waste can leave the body and be… Immune Thrombocytopenia Immune thrombocytopenia (ITP) is a condition in which the immune system mistakenly attacks the body’s own platelets, leaving too few of the tiny cells… Imperforate Hymen Imperforate hymen is a common congenital difference in which the thin membrane at the vaginal opening has no hole, so menstrual blood and normal… Impetigo is a common and highly contagious bacterial skin infection that causes red sores and golden, honey-coloured crusts, most often around the… Incontinence is the accidental or involuntary loss of urine or stool — a common and very treatable problem, not an inevitable part of getting older. Infectious Diseases Infectious diseases are illnesses caused by tiny living things — bacteria, viruses, fungi and parasites — that get into the body and multiply, often… Ingrown toenail

An ingrown toenail is a common problem in which the edge of a nail grows into the soft skin beside it, causing pain, redness and swelling — most often… Insomnia is a common sleep problem in which you regularly find it hard to fall asleep, stay asleep, or get back to sleep — leaving you tired and below… Internet Addiction Internet addiction is a pattern of online use — gaming, social media, streaming or browsing — that a person finds hard to control and that begins to… Interstitial Cystitis Interstitial cystitis is a long-term condition in which the bladder becomes painful and over-sensitive, causing pelvic pain and a frequent, urgent… Iron Deficiency Anemia Iron deficiency anaemia is a common condition in which the body does not have enough iron to make healthy red blood cells, so less oxygen is carried… Irritated skin is skin that has become red, itchy, sore or inflamed — a common reaction to something it has touched, an underlying skin condition, or… Jaundice is a yellowing of the skin and the whites of the eyes that appears when a yellow pigment called bilirubin builds up in the blood. Jock itch is a common fungal infection of the skin in the groin and inner thighs, causing an itchy, red or discoloured rash that often spreads… Kawasaki Disease Kawasaki disease is a rare illness of early childhood in which the immune system briefly inflames blood vessels throughout the body, most importantly… A keloid is a firm, raised scar that keeps growing beyond the edges of the original wound, spreading into nearby healthy skin as the body makes too… The ketogenic diet is a very low-carbohydrate, high-fat way of eating that shifts the body into burning fat for fuel instead of sugar. Kidney cancer is a condition in which cells in one of the kidneys begin to grow and divide abnormally, forming a tumour that can gradually spread if… Kidney Diseases Kidney disease is any condition in which the kidneys become damaged and can no longer filter the blood as well as they should, allowing waste and… Kidney Infection A kidney infection is a painful illness that happens when bacteria travel up the urinary tract and take hold in one or both kidneys, causing fever… Kidney stones are hard, pebble-like pieces that form when minerals and salts in the urine become concentrated and crystallise inside the kidneys or… Kids’ health is the everyday care that helps children grow, learn and feel their best — from healthy eating and sleep to vaccinations, safety and… Klebsiella is a group of common bacteria that live harmlessly in the gut and environment but can cause serious infections — especially in hospitals… Klinefelter Syndrome Klinefelter syndrome is a common genetic condition in which a boy or man is born with an extra copy of the X chromosome, which mainly affects how the… Knee pain is discomfort in or around the knee joint — one of the most common everyday complaints, ranging from a passing ache after activity to a… Labyrinthitis is inflammation of the labyrinth, the delicate balance-and-hearing structure deep inside the ear, which can bring on sudden dizziness, a… Lactose Intolerance Lactose intolerance is a common digestive problem in which the body cannot fully break down lactose — the natural sugar in milk and dairy — leading to… A laminectomy is a spinal operation that removes a small section of bone from the back of a vertebra to relieve pressure on the spinal cord or nerves. Laparoscopy is a type of keyhole surgery that lets a surgeon look inside your abdomen or pelvis, and often treat a problem, through one or more small… Leg pain is any aching, cramping, throbbing or sharp discomfort felt anywhere from the hip to the foot, and it is one of the most common reasons… Lemierre's Syndrome Lemierre’s syndrome is a rare but serious complication of a bacterial throat infection, in which the infection spreads into the neck and causes an… Leprosy, also called Hansen’s disease, is a slow-growing bacterial infection that mainly affects the skin and the nerves — and it is fully curable… Leptospirosis is a bacterial infection caught from water or soil contaminated with the urine of infected animals, ranging from a mild flu-like illness… Leukaemia is a cancer of the blood-forming tissue in the bone marrow, in which the body makes large numbers of abnormal white blood cells that crowd… LGBTQ+ health is the whole-person care of lesbian, gay, bisexual, transgender, queer and other sexual and gender minority people — covering the same… Lice are tiny wingless insects that live on the body and feed on small amounts of blood, most often causing an itchy infestation of the scalp and hair… A lipoma is a soft, harmless lump of fatty tissue that grows slowly just under the skin, and is one of the most common non-cancerous growths in… Listeria is a hardy bacterium found in soil, water and some foods that can cause a serious infection called listeriosis, particularly in pregnancy… Liver cancer is a serious condition in which cells in the liver grow out of control, either starting in the liver itself (primary) or spreading to it… Liver disease is a broad term for any condition that damages the liver and stops it working as it should, from a build-up of fat to long-term… A lobectomy is an operation to remove one lobe — a distinct section — of an organ, most often a lobe of a lung, but sometimes of the liver, thyroid or… Loneliness is the painful feeling that the connection you have with others falls short of the connection you want — a normal human emotion that can… Longevity is the science and everyday practice of living a longer life while staying healthy, active and independent for as much of it as possible. Low Testosterone Low testosterone, also called male hypogonadism, is when the body does not make enough of the hormone testosterone, which can affect energy, mood, sex… Lung and Respiratory The lungs and respiratory system are the network of airways and air sacs that draw oxygen into the body and clear away carbon dioxide with every… Lung cancer is a growth of abnormal cells that begins in the tissue of the lungs, usually in the lining of the airways, and can spread to other parts… Lupus is a long-term autoimmune condition in which the immune system mistakenly attacks healthy tissue, causing inflammation that can affect the skin… Luteinizing Hormone Luteinizing hormone (LH) is a chemical messenger from the brain that steers the ovaries and testes — triggering the release of an egg in women and the… Lyme disease is a bacterial infection spread to people through the bite of an infected tick, and it can affect the skin, joints, nervous system and… Lymph nodes are small, bean-shaped glands scattered throughout the body that act as filters and checkpoints for the immune system, helping to trap… Lymphoma is a cancer of the lymphatic system — the network of vessels and glands that helps fight infection — in which white blood cells called… Macular Degeneration Macular degeneration is a common eye condition in which the macula — the small central part of the retina — gradually stops working properly, blurring… Malaria is a serious infection spread by the bite of certain mosquitoes carrying tiny parasites that invade and destroy red blood cells, causing… Marijuana, also called cannabis, is a plant whose dried leaves and flowers are used for their mind-altering and, increasingly, their medicinal… Measles is a highly contagious infection caused by the measles virus, which spreads easily through coughs and sneezes and produces a fever followed by… Medical Marijuana Medical marijuana — also called medical cannabis — is the use of the cannabis plant, or chemicals derived from it, to relieve symptoms of certain… Medicare is the United States’ federal health-insurance programme, designed mainly for people aged 65 and over and for some younger people with… Meditation is a simple, learnable practice of training your attention — usually by focusing on the breath, the body or the present moment — to steady… Mediterranean Diet The Mediterranean diet is a way of eating inspired by the traditional foods of countries around the Mediterranean Sea, built on vegetables, fruit… Melanoma is a serious form of skin cancer that begins in the melanocytes — the cells that give skin its colour — and can spread to other parts of the… Men’s health covers the physical and mental wellbeing of men across a lifetime — from everyday habits like sleep and exercise to the checks and… Meningitis is inflammation of the meninges — the protective membranes that wrap around the brain and spinal cord — most often caused by an infection… Menopause is the natural life stage when a woman’s periods stop for good and the ovaries wind down, marking the end of the reproductive years rather… Menstrual Cramps Menstrual cramps are the throbbing or aching pains in the lower belly that many women feel just before and during a period, as the womb tightens to… Menstruation is the monthly shedding of the womb’s lining — the visible part of a natural cycle that prepares the body for a possible pregnancy each… Middle East Respiratory Syndrome Middle East respiratory syndrome (MERS) is a viral illness of the lungs and airways, caused by a coronavirus, that can range from a mild cold-like… Migraine is a common neurological condition that causes attacks of moderate-to-severe headache, often on one side of the head and usually alongside… Miscarriage is the loss of a pregnancy during the first 23 weeks — a common experience that, in the great majority of cases, happens through no fault… Molluscum Contagiosum Molluscum contagiosum is a common, harmless viral skin infection that produces small, firm, pearly bumps and usually clears on its own without… Mpox (formerly called monkeypox) is a viral infection that spreads mainly through close contact and usually causes a fever followed by a distinctive… Mononucleosis, better known as glandular fever, is a common viral infection that causes a sore throat, swollen glands and weeks of unusual tiredness… Mouth lesions are sores, patches, lumps or ulcers that appear on the lips, gums, tongue or inside of the mouth — most are harmless and short-lived… Mucopolysaccharidosis IV A Mucopolysaccharidosis IV A, also called Morquio A syndrome, is a rare inherited condition in which the body cannot fully break down certain sugar… Magnetic resonance imaging Magnetic resonance imaging (MRI) is a scan that uses a strong magnetic field and radio waves to create detailed pictures of the inside of the body —… Mucus is the slippery, protective fluid your body makes to line and moisten the airways, gut and other passages — trapping germs and dust so they can… Multiple Myeloma Multiple myeloma is a cancer of the plasma cells — a type of white blood cell in the bone marrow — which multiply out of control and crowd out the… Multiple Sclerosis Multiple sclerosis (MS) is a long-term condition in which the immune system mistakenly attacks the protective covering around nerves in the brain and… Myasthenia Gravis Myasthenia gravis is a long-term autoimmune condition in which the immune system disrupts the signals between nerve and muscle, causing muscles to… Mycoplasma Genitalium Mycoplasma genitalium is a tiny sexually transmitted bacterium that can infect the genital and urinary tract, often causing no symptoms at all but… Myocarditis is inflammation of the heart muscle — the myocardium — which can weaken the heart, disturb its rhythm and, in more serious cases, affect… Myopia, or short-sightedness, is a very common vision condition in which distant objects look blurred while things close up stay clear. Narcissistic personality disorder is a mental-health condition in which a long-standing pattern of grandiosity, a strong need for admiration and… Narcolepsy is a long-term neurological condition in which the brain cannot reliably control the boundary between sleep and wakefulness, causing… Nausea is the uneasy, queasy feeling that you might be about to vomit — a warning sign rather than an illness in its own right. Neck pain is a very common ache or stiffness in the muscles, joints and other tissues of the neck — usually short-lived and rarely a sign of anything… Necrotizing Fasciitis Necrotizing fasciitis is a rare but life-threatening bacterial infection that spreads rapidly through the soft tissue beneath the skin, destroying it… Neurology is the branch of medicine that deals with the brain, spinal cord and nerves — the vast communication network that controls movement… Peripheral neuropathy is damage to the nerves that run outside the brain and spinal cord, disrupting the signals that pass between the body and the… Neurotransmitters Neurotransmitters are the body’s chemical messengers — tiny molecules that carry signals between nerve cells and shape how you move, think, feel and… National Early Warning Score The National Early Warning Score (NEWS) is a simple bedside scoring system that turns a patient’s vital signs into a single number, helping staff spot… Night sweats are repeated episodes of heavy sweating during sleep — enough to soak your bedclothes or sheets — that are not simply caused by a hot… Non-Hodgkin Lymphoma Non-Hodgkin lymphoma is a cancer that starts in the lymphatic system — the network of vessels, glands and organs that helps the body fight infection —… Norepinephrine is a natural chemical that acts as both a hormone and a nerve messenger, helping your body stay alert and ready to respond — a key… Norovirus is a highly contagious virus that inflames the stomach and intestines, causing sudden bouts of vomiting and diarrhoea — the illness many… Nutrients are the substances in food that your body uses to grow, repair itself, and power everything it does — from a beating heart to a passing… Obesity is a common, long-term health condition in which excess body fat builds up over time to a level that can affect a person’s health — not a… Obsessive-compulsive disorde Obsessive-compulsive disorder (OCD) is a common mental health condition in which recurring unwanted thoughts (obsessions) drive a person to carry out… Omega-3 Fatty Acids Omega-3 fatty acids are a family of healthy fats that the body cannot make in large amounts, so we need to get them from food — especially oily fish… An oncologist is a doctor who specialises in diagnosing, treating and supporting people through cancer — guiding care from the first tests to recovery… Ophthalmologist An ophthalmologist is a medical doctor who specialises in the eyes — diagnosing and treating everything from routine vision problems to complex eye… Opioid Addiction Opioid addiction, also called opioid use disorder, is a treatable medical condition in which the brain becomes dependent on opioids — making it hard… Optic neuritis is inflammation of the optic nerve — the cable that carries visual signals from the eye to the brain — which typically causes sudden… An optometrist is a trained eye-care professional who examines your eyes, tests your vision, prescribes glasses or contact lenses, and checks for… Oral health is the day-to-day care of your teeth, gums and mouth — keeping them clean, comfortable and free of disease so you can eat, speak and smile… Oral and Head and Neck Cancer Oral, head and neck cancer is a group of cancers that start in the mouth, throat, voice box and nearby areas, most often in the flat cells that line… Osteoarthritis is the most common form of arthritis, in which the smooth cartilage that cushions a joint gradually wears down, leaving the bones to… Osteoporosis is a common condition in which the bones gradually lose their strength and density, making them fragile and far more likely to break. Ovarian cancer is a growth of abnormal cells that begins in an ovary or a fallopian tube, most often in women past the menopause and frequently… An ovarian cyst is a fluid-filled sac that forms on or inside an ovary — extremely common, usually harmless, and in most cases clearing away on its… Oxytocin is a natural hormone made in the brain that supports bonding, childbirth and breastfeeding — and helps calm the body during warm, trusting… Pseudomonas aeruginosa Pseudomonas aeruginosa is a common environmental bacterium that rarely troubles healthy people but can cause stubborn infections in those who are… Paget's Disease of the Breast Paget’s disease of the breast is a rare form of breast cancer that appears on the skin of the nipple and the darker area around it, and is very often… Pulmonary Arterial Hypertension Pulmonary arterial hypertension is a serious, progressive condition in which the small arteries carrying blood through the lungs become narrowed and… Pain Management Pain management is the range of treatments and everyday strategies used to ease pain, restore function and improve quality of life — whether the pain… The paleo diet is an eating pattern built around whole foods thought to resemble those our hunter-gatherer ancestors ate — meat, fish, eggs… Pancreatic Cancer Pancreatic cancer is a growth of abnormal cells that begins in the pancreas — the organ behind the stomach that helps digest food and control blood… Pancreatitis is inflammation of the pancreas, the gland behind the stomach that makes digestive juices and the hormones that control blood sugar. Panic disorder is an anxiety condition in which a person has repeated, unexpected panic attacks — sudden surges of intense fear with strong physical… A Pap smear is a quick, routine test that gently collects a few cells from the cervix to check for early changes that could, over time, lead to… Parkinson's Disease Parkinson’s disease is a progressive condition of the nervous system in which cells deep in the brain are gradually lost, affecting the way the body… Paroxysmal Nocturnal Hemoglobinuria Paroxysmal nocturnal haemoglobinuria (PNH) is a rare, acquired blood disorder in which a fault in the bone marrow leaves red blood cells unprotected… Polycystic ovary syndrome Polycystic ovary syndrome (PCOS) is a common long-term hormonal condition in which the ovaries and the body’s hormone balance work differently… Pediatric Oncologist A pediatric oncologist is a doctor who specialises in diagnosing and treating cancer in babies, children and teenagers. A pediatrician is a doctor who specialises in the health of babies, children and teenagers — from routine check-ups and vaccinations to diagnosing and… A peptic ulcer is an open sore that forms in the lining of the stomach or the first part of the small intestine, where digestive acid has worn through… Pericarditis is inflammation of the pericardium — the thin, fluid-filled sac that surrounds the heart — and it typically causes sharp chest pain that… Periodontal Disease Periodontal disease is a serious, long-term gum infection that damages the soft tissue and bone supporting the teeth, and is the leading cause of… Peritonitis is inflammation of the peritoneum — the thin membrane lining the inside of the abdomen — and is almost always a medical emergency that… Personality Disorder A personality disorder is a long-term pattern of thinking, feeling and relating to others that differs markedly from what is usually expected, and… Pet health looks at how living with animals shapes our own wellbeing — the real benefits pets bring, the small risks worth knowing, and the everyday… Pharyngitis is inflammation of the pharynx — the back of the throat — which makes it feel sore, scratchy or painful, especially when you swallow. Pelvic inflammatory disease Pelvic inflammatory disease (PID) is an infection of the upper female reproductive organs — the womb, fallopian tubes and ovaries — that most often… A pilonidal cyst is a small pocket that forms under the skin at the top of the buttock crease, just above the tailbone, and often fills with hair and… Pink Eye - Conjunctivitis Pink eye, or conjunctivitis, is inflammation of the thin, clear membrane that covers the white of the eye and lines the inside of the eyelids, making… Pinworms are tiny, thread-like worms that live in the gut and cause an itchy bottom — a very common and harmless infection, especially in young… Plantar fasciitis Plantar fasciitis is a common cause of heel pain, in which the thick band of tissue that supports the arch of the foot becomes irritated and painful… Pneumonia is an infection that inflames the tiny air sacs deep in one or both lungs, causing them to fill with fluid or pus and making it harder to… Poison ivy rash is an itchy, blistering skin reaction caused by touching urushiol, the oily sap found in poison ivy and its close relatives. Postpartum Depression Postpartum depression is a common and treatable form of depression that can develop after having a baby, bringing persistent low mood and other… Postpartum Psychosis Postpartum psychosis is a rare but serious mental illness that can develop in the days or weeks after giving birth, causing a sudden loss of touch… Postural Orthostatic Tachycardia Postural orthostatic tachycardia syndrome (POTS) is a disorder of the automatic nervous system in which the heart rate rises sharply on standing up… Prader Willi Syndrome Prader-Willi syndrome is a rare genetic condition, present from birth, that disrupts a small control centre in the brain and affects appetite, growth… Preconception care is the health preparation you do in the months before trying for a baby, giving your body the best possible starting point for… Prediabetes is a warning stage in which blood sugar is higher than normal but not yet high enough to be called type 2 diabetes — and it can often be… Preeclampsia is a pregnancy complication in which raised blood pressure and signs of organ strain — usually in the kidneys or liver — develop after… Pregnancy is the roughly nine-month journey during which a fertilised egg grows into a baby inside the womb, bringing wide-ranging changes to a… Premenstrual Syndrome Premenstrual syndrome (PMS) is the pattern of physical and emotional symptoms that many women and people who menstruate notice in the days before a… Presbyopia is the gradual, age-related loss of the eye’s ability to focus on close objects, making small print and near tasks harder to see clearly. Primary Biliary Cirrhosis Primary biliary cholangitis is a long-term autoimmune condition in which the immune system slowly damages the small bile ducts inside the liver… Probiotics are live “friendly” bacteria and yeasts that, taken in useful amounts, can help support the natural community of microbes living in your… Progesterone is a key female sex hormone that prepares the womb for pregnancy each month and helps support a pregnancy once it begins. Prolactin is a hormone made in the brain whose best-known job is to stimulate the breasts to produce milk after childbirth — though it plays quieter… Prostaglandins are hormone-like chemicals your body makes at the site of an injury or need, driving processes such as inflammation, pain, fever, blood… The prostate is a small gland that sits at the base of the bladder in men and people assigned male at birth, and its main job is to help make the… Prostate Cancer Prostate cancer is a cancer that develops in the prostate, a small gland in men that sits below the bladder and helps make the fluid part of semen. Prostate Health The prostate is a small gland that sits just below a man’s bladder and helps make the fluid that carries and nourishes sperm. A prostatectomy is an operation to remove part or all of the prostate gland, most often to treat prostate cancer or a much-enlarged prostate that is… Protein is one of the three main nutrients in food — the body’s essential building material for muscle, skin, hormones and much of the machinery that… Psoriasis is a common long-term autoimmune condition in which skin cells are made far too quickly, building up into raised, scaly patches called… Psoriatic Arthritis Psoriatic arthritis is a long-term inflammatory joint condition, linked to the skin disease psoriasis, in which an overactive immune system attacks… A psychiatrist is a medical doctor who specialises in diagnosing and treating mental health conditions, and who can prescribe medication as part of… A psychologist is a trained mental-health professional who helps people understand their thoughts, feelings and behaviour, and uses talking therapies… Psychosis is a state of mind in which a person loses some contact with reality — hearing, seeing or believing things that others do not — making it… Post-traumatic stress disorder Post-traumatic stress disorder (PTSD) is a mental health condition that can develop after a frightening, distressing or life-threatening experience… Pubic lice are tiny insects that live in coarse body hair — most often the pubic hair — and feed on small amounts of blood, causing itching in the… Public health is the science and practice of protecting and improving the health of whole communities — not one patient at a time, but by preventing… Pulmonary Embolism A pulmonary embolism is a sudden blockage in one of the arteries of the lungs, usually caused by a blood clot that has travelled up from a deep vein… Pyelonephritis is a kidney infection — a type of urinary tract infection in which bacteria travel up from the bladder into one or both kidneys… Quarantine is a public-health measure that separates and restricts the movement of people who may have been exposed to a contagious disease, to see… Quitting Smoking Quitting smoking is one of the single most powerful things you can do for your health — and although it is hard, millions of people succeed every… Rabies is a viral infection that attacks the brain and nerves after the bite of an infected animal — almost always fatal once symptoms begin, yet… A rare disease is a condition that affects only a small number of people — yet because there are thousands of them, rare diseases together touch… Razor burn is a short-lived skin irritation — redness, stinging and a mild rash — that appears soon after shaving and usually settles within a day or… Rectal Bleeding Rectal bleeding means passing blood from the back passage — often noticed as bright red streaks on toilet paper, spots in the bowl, or blood mixed… Rectal Prolapse Rectal prolapse is a condition in which part or all of the rectum — the last section of the large bowel — slips down and turns inside out, so that it… Resilience is the ability to adapt to stress, hardship and change — to bend under pressure and recover rather than break. Respiratory Syncytial Virus Respiratory syncytial virus (RSV) is a very common, highly contagious virus that infects the airways and lungs — usually mild in healthy adults, but a… Restless Legs Syndrome Restless legs syndrome is a common nervous-system condition that causes an overwhelming urge to move the legs, usually alongside uncomfortable… Rheumatic Diseases Rheumatic diseases are a large family of long-term conditions that cause pain, swelling and stiffness in the joints, muscles and connective tissues —… Rheumatoid Arthritis Rheumatoid arthritis is a long-term autoimmune condition in which the body’s immune system attacks the lining of the joints, causing pain, swelling… Ringworm is a common, contagious fungal infection of the skin that produces a red, scaly, ring-shaped patch — despite its name, no worm is involved. Rosacea is a common long-term skin condition that mainly affects the face, causing persistent redness, flushing and, in some people, small bumps and… Salicylates are a family of medicines — aspirin is the best known — that ease pain, calm inflammation, lower fever and, in low doses, help keep blood… Salmonella is a group of bacteria that live in the gut of many animals and are a leading cause of food poisoning, typically producing several days of… Sarcoidosis is an inflammatory condition in which tiny clumps of immune cells, called granulomas, build up in one or more organs — most often the… Severe Acute Respiratory Syndrome Severe acute respiratory syndrome (SARS) is a serious viral lung infection, caused by a coronavirus, that spreads between people and can cause severe… Saturated fat is a type of dietary fat found mainly in animal products and a few tropical oils, and eating a lot of it can raise the level of… Scabies is a common, treatable skin condition caused by a tiny mite that burrows into the top layer of skin, producing an intensely itchy rash. Scarlet fever is a bacterial infection that mainly affects young children, causing a distinctive pink-red rash alongside a sore throat and a high… Schizophrenia is a long-term mental health condition that changes how a person thinks, feels and understands the world, sometimes making it hard to… Sciatica is pain that travels along the path of the sciatic nerve — from the lower back, through the buttock and down the back of the leg — usually… Seasonal Allergies Seasonal allergies, often called hay fever, are an over-reaction of the immune system to airborne pollen and mould spores that appear at certain times… Seasonal Skin Guide Your skin is a living barrier that meets the weather head-on, so the way you care for it should shift with the seasons — what soothes in dry winter… A sebaceous cyst is a small, harmless lump under the skin that forms when a skin gland or duct becomes blocked and slowly fills with a soft… Self-care is the everyday practice of looking after your own physical, mental and emotional health — the small, deliberate habits that keep you well… Senior health is about helping older adults stay active, independent and well — managing the natural changes of ageing while preventing and treating… Sepsis is a life-threatening emergency in which the body’s response to an infection turns against its own tissues and organs, and it needs urgent… Septoplasty is a common operation to straighten the thin wall of bone and cartilage between your nostrils, opening up a blocked nose so you can… Serotonin is a natural chemical messenger that helps carry signals between nerve cells, shaping mood, sleep, appetite and digestion throughout the… Sexual health is about more than avoiding infection or pregnancy — it means having a safe, respectful and enjoyable relationship with your own body… Shingles is a painful rash caused by the reactivation of the chickenpox virus, which stays dormant in the body for years after a childhood infection. Sickle Cell Anemia Sickle cell anaemia is an inherited blood disorder in which red blood cells become stiff and crescent-shaped, so they carry less oxygen and can block… Sinus Infection A sinus infection, or sinusitis, is inflammation of the sinuses — the air-filled spaces behind the cheeks, forehead and eyes — which usually follows a… Sjogren's Syndrome Sjögren’s syndrome is a long-term autoimmune condition in which the immune system mistakenly attacks the glands that make tears and saliva, leading to… Skin and Beauty Skin and beauty is about keeping the body’s largest organ — your skin — healthy, comfortable and resilient, while understanding the routines and… Skin cancer is the abnormal growth of skin cells, most often caused by ultraviolet light from the sun or sunbeds, and it is one of the most common… A skin lump is any bump, swelling or raised area under or on the skin — most are harmless, but a few need a doctor’s eye to be sure. Skin self-care is the everyday routine of cleansing, protecting and watching your skin so it stays comfortable, resilient and healthy over a lifetime. Sleep apnoea is a common condition in which breathing repeatedly stops and starts during sleep, briefly starving the body of oxygen and disturbing… Sleep Disorders Sleep disorders are conditions that disturb the length, timing or quality of your sleep often enough to affect how you feel and function during the… Sleep Paralysis Sleep paralysis is a temporary and harmless inability to move or speak that happens as you are falling asleep or waking up, often lasting only a few… Sleepwalking is a common sleep behaviour in which a person gets up and walks about, or carries out other actions, while still deeply asleep and… Smart Skin is a practical, evidence-based approach to looking after your skin — protecting it, keeping it comfortable, and knowing which changes are… Social Anxiety Disorder Social anxiety disorder is a common mental-health condition in which everyday social situations bring on an intense, lasting fear of being watched… A sore throat is pain, scratchiness or irritation of the throat that often feels worse when you swallow — one of the most common reasons people feel… Methicillin-resistant Staphylococcus aureus Methicillin-resistant Staphylococcus aureus (MRSA) is a common bacterium that has become resistant to several of the antibiotics normally used to… Sexually Transmitted Infections Sexually transmitted infections (STIs) are common infections passed from one person to another mainly through sexual contact, and most are easy to… A stent is a small, expandable tube that a doctor places inside a narrowed or weakened passage in the body — most often an artery — to hold it open… Stomach cancer is a growth of abnormal cells that begins in the lining of the stomach and can spread deeper into its wall and beyond if it is not… Stopping smoking is the single most powerful step most people can take for their health — and the body begins to repair itself within hours of the… Strabismus, often called a squint, is a condition in which the eyes do not point in the same direction — one eye may turn in, out, up or down while… Streptococcus is a large family of common bacteria — some harmless, others responsible for everyday infections like strep throat as well as more… Stress is the body’s natural response to pressure — a burst of alertness that helps you meet a challenge, but which can wear you down when it never… A stroke is a medical emergency in which the blood supply to part of the brain is cut off, starving brain cells of oxygen so that they begin to die… Dietary supplements are products — pills, capsules, powders, gummies or liquids — taken to add nutrients or other substances to your diet, from… Syphilis is a sexually transmitted infection caused by bacteria that, left untreated, moves through distinct stages over months or years — yet is… Tardive Dyskinesia Tardive dyskinesia is a movement disorder that causes repetitive, involuntary movements — most often of the face, mouth and tongue — usually after… Testicular Cancer Testicular cancer is a growth of abnormal cells in a testicle — the paired organs held in the scrotum — and is one of the most treatable of all… Testosterone is the main sex hormone in men and a smaller but important one in women, shaping the body during puberty and helping keep muscle, bone… Tetanus is a serious but rare infection in which a toxin made by bacteria in a wound attacks the nerves, causing painful muscle stiffness and spasms —… Thrush is a common infection caused by an overgrowth of a yeast called Candida, most often affecting the mouth and throat or the genital area, where… Thyroid cancer is a growth of abnormal cells that begins in the thyroid — the small, butterfly-shaped gland in the front of the neck that helps… Thyroid Conditions Thyroid conditions are problems with the small gland in the neck that makes the hormones controlling how fast the body uses energy, so it runs either… Thyroid-Stimulating Hormone Thyroid-stimulating hormone (TSH) is the body’s master signal for the thyroid gland, telling it how much thyroid hormone to make and release into the… A thyroidectomy is an operation to remove all or part of the thyroid, the small butterfly-shaped gland in the neck that helps control the body’s… Transient Ischemic Attack A transient ischaemic attack (TIA), often called a mini-stroke, is a brief interruption of the blood supply to part of the brain that causes… Tinea Versicolor Tinea versicolor is a common, harmless skin condition in which a yeast that normally lives on the skin grows a little too freely, leaving patches that… Toenail fungus is a common infection in which fungi invade the nail, leaving it thickened, discoloured and crumbly — usually harmless but often slow… Tonsil stones are small, hard lumps of trapped debris that form in the little pockets on the surface of the tonsils — harmless, but often the cause of… A tonsillectomy is a surgical operation to remove the tonsils — the two soft pads of tissue at the back of the throat — usually to stop repeated… Tonsillitis is inflammation of the tonsils — the two soft glands at the back of the throat — usually caused by a viral or bacterial infection. Toxoplasmosis is a common infection caused by a tiny parasite called Toxoplasma gondii , which usually causes no symptoms but can be serious during… A tracheostomy is a surgical opening made in the front of the neck and into the windpipe, holding a small tube in place so that air can reach the… Trauma is physical injury to the body caused by a sudden external force — such as a fall, road accident, blow or burn — and, in a broader sense, the… Trichomoniasis is a common sexually transmitted infection caused by a tiny parasite, which often produces no symptoms yet is straightforward to cure… Triple X Syndrome Triple X syndrome is a genetic condition in which a girl or woman is born with an extra X chromosome in her cells, and it is often so mild that many… Tubal ligation is a surgical form of permanent contraception in which a woman’s fallopian tubes are blocked, sealed or cut so that eggs and sperm can… Tuberculosis (TB) is an infectious disease caused by a slow-growing bacterium that most often attacks the lungs, but which can affect almost any part… Turner Syndrome Turner syndrome is a genetic condition affecting girls and women, in which one of the two X chromosomes is missing or only partly present, chiefly… Type 1 Diabetes Type 1 diabetes is a lifelong autoimmune condition in which the body stops making insulin, so blood sugar rises unless insulin is replaced every day. Type 2 Diabetes Type 2 diabetes is a common long-term condition in which the body cannot use insulin properly, so the level of sugar (glucose) in the blood becomes… A peptic ulcer is an open sore that develops on the inside lining of the stomach or the upper part of the small intestine, where acid and digestive… Ulcerative Colitis Ulcerative colitis is a long-term condition in which the lining of the large bowel becomes inflamed and develops tiny ulcers, causing bouts of bloody… An ultrasound scan uses high-frequency sound waves to create live pictures of the inside of your body, without any radiation or needles. Urinary Conditions Urinary conditions are problems affecting the organs that make, store and pass urine — the kidneys, ureters, bladder and urethra — ranging from common… Urinary Tract Infection A urinary tract infection (UTI) is an infection of any part of the system that makes and carries urine — most often the bladder — usually caused by… Urine is the liquid waste your kidneys produce as they filter your blood, carrying away extra water, salts and by-products your body no longer needs. Uterine cancer is a cancer that begins in the womb (uterus), most often in its lining — the endometrium — and usually shows itself early through… Uterine Fibroids Uterine fibroids are common, non-cancerous growths that develop in or around the womb (uterus), most often during the childbearing years. Vaccines are medicines that teach your immune system to recognise and fight a specific germ, giving you protection against an illness before you ever… Vaginal Bleeding Vaginal bleeding is any bleeding that comes from the vagina, whether it is a normal monthly period or bleeding that happens at an unexpected time. Vaginal Discharge Vaginal discharge is the fluid that naturally flows from the vagina to keep it clean, moist and protected — and most of the time it is a sign that… Vaginal Dryness Vaginal dryness is a common and very treatable problem in which the tissues lining the vagina become thinner, less elastic and short of their natural… Vaginal Flatulence Vaginal flatulence — often called “queefing” — is the release of trapped air from the vagina, usually making a sound like passing wind but without… Vaginal health is the day-to-day wellbeing of the vagina and vulva — a naturally self-cleaning, finely balanced part of the body that stays… Vaginal Itching Vaginal itching is an uncomfortable urge to scratch the vulva or vagina — a common, usually harmless symptom that can be triggered by irritation… Vaginal odor is the natural smell of the vagina and vulva — a mild scent that shifts through the month and is usually a sign of a healthy… Vaginal Prolapse Vaginal prolapse is when one or more of the pelvic organs slip down from their normal position and bulge into the vagina, because the muscles and… Vaginitis is inflammation of the vagina that causes symptoms such as unusual discharge, itching and soreness, and is most often the result of a change… A varicocele is an enlargement of the veins inside the scrotum — rather like a varicose vein — caused by blood pooling instead of draining away as it… Vasopressin is a hormone that helps your body hold on to water, keeping your fluids and blood pressure in balance. Vertebral Stenosis Spinal stenosis is a narrowing of the spaces inside the spine that puts pressure on the spinal cord and the nerves running through it, most often in… Vestibular Neuritis Vestibular neuritis is a sudden inner-ear disorder in which the balance nerve becomes inflamed, usually after a viral infection, causing intense… Vision is the sense that lets you see — the way your eyes gather light and your brain turns it into the sharp, colourful, moving picture of the world… Vitamin B12 Deficiency Vitamin B12 deficiency is a shortage of the vitamin your body needs to make healthy red blood cells and keep the nervous system working, most often… Vitamin D is a nutrient your body needs to keep bones, muscles and the immune system working — and unusually, your skin can make most of it from… Vitamins are essential nutrients your body needs in small amounts to grow, repair itself and keep its many systems running smoothly. Vitiligo is a long-term condition in which patches of skin lose their colour, because the cells that make pigment stop working or are destroyed. Vomiting is the forceful emptying of the stomach through the mouth — the body’s way of expelling something it decides is harmful or of responding to a… Vancomycin-Resistant Enterococci Vancomycin-resistant enterococci (VRE) are common gut bacteria that have become resistant to vancomycin, an antibiotic often held in reserve for… Vulvodynia is persistent pain or discomfort of the vulva — the skin around the opening of the vagina — that lasts at least three months and has no… Wallenberg Syndrome Wallenberg syndrome is a type of stroke caused by a loss of blood supply to the lateral part of the brainstem, producing a distinctive mix of balance… Your weight is one part of the bigger picture of health — shaped by food, movement, sleep, genes and hormones, and best understood alongside how you… West Nile virus is a mosquito-borne infection that usually causes no symptoms or a mild, flu-like illness, but in a small number of people it can… Whiplash is a neck injury caused by a sudden, forceful back-and-forth movement of the head that overstretches the soft tissues of the neck. Whipple Disease Whipple disease is a rare bacterial infection that mainly attacks the small intestine, stopping the body from absorbing food properly and, over time… Whooping cough, or pertussis, is a bacterial infection of the airways that causes long bouts of coughing and can be serious, especially for young… Wisdom teeth are the third and final set of molars at the very back of the mouth, which usually appear in the late teens or early twenties — and often… Women’s health covers the conditions, checks and everyday choices that shape a woman’s wellbeing across every stage of life — from the first period to… An X-ray is a quick, painless imaging test that uses a small amount of radiation to create pictures of the inside of your body — most often to look at… Xerosis, better known as dry skin, is a very common and usually minor condition in which the skin loses moisture and its protective barrier, leaving… XYY syndrome is a genetic condition in which a boy or man is born with an extra Y chromosome in his cells, most often causing few or very mild… Yeast Infection A yeast infection is a very common, easily treated overgrowth of a yeast called Candida, most often affecting the vagina and vulva and causing… Yellow fever is a serious viral infection spread by the bite of infected mosquitoes in parts of Africa and South America, and prevented very… Yoga is a mind-and-body practice that combines physical postures, controlled breathing and focused attention to build strength, flexibility and a… Zika is a viral infection spread mainly by mosquito bites that usually causes only mild illness, but can seriously harm a baby if it is caught during…