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Health Conditions


See below a list of health conditions and the supplements that have effects on them, backed by scientific studies from the U.S. National Library of Medicine.

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A


Acne
Acne is a common skin disease that causes pimples. Pimples form when hair follicles under your skin clog up. Most pimples form on the face, neck, back, chest, and shoulders. Anyone can get acne, but it is common in teenagers and young adults. It is not serious, but it can cause scars.

Acute Bronchitis
Bronchitis is an inflammation of the bronchial tubes, the airways that carry air to your lungs. It causes a cough that often brings up mucus. It can also cause shortness of breath, wheezing, a low fever, and chest tightness. There are two main types of bronchitis: acute and chronic.

Acute Mountain Sickness
Nearly one in four people who ascend to 2,600 meters (8,500 feet) above sea level develop symptoms referred to as acute mountain sickness (AMS).

ADHD
Is it hard for your child to sit still? Does your child act without thinking first? Does your child start but not finish things? If so, your child may have attention deficit hyperactivity disorder (ADHD). Nearly everyone shows some of these behaviors at times, but ADHD lasts more than 6 months and causes problems in school, at home and in social situations.

Aggression
A type of behaviour intending to cause physical or mental harm.

Alcohol Use Disorder
For most adults, moderate alcohol use is probably not harmful. However, about 18 million adult Americans have an alcohol use disorder (AUD). This means that their drinking causes distress and harm. AUD can range from mild to severe, depending on the symptoms. Severe AUD is sometimes called alcoholism or alcohol dependence.

Allergy
An allergy is a reaction by your immune system to something that does not bother most other people. People who have allergies often are sensitive to more than one thing.

Alzheimer's Disease
Alzheimer's disease (AD) is the most common form of dementia among older people. Dementia is a brain disorder that seriously affects a person's ability to carry out daily activities.

Anemia
If you have anemia, your blood does not carry enough oxygen to the rest of your body. The most common cause of anemia is not having enough iron. Your body needs iron to make hemoglobin. Hemoglobin is an iron-rich protein that gives the red color to blood. It carries oxygen from the lungs to the rest of the body.

Anxiety
Anxiety is a feeling of fear, dread, and uneasiness. It might cause you to sweat, feel restless and tense, and have a rapid heartbeat. It can be a normal reaction to stress. For example, you might feel anxious when faced with a difficult problem at work, before taking a test, or before making an important decision. It can help you to cope. The anxiety may give you a boost of energy or help you focus. But for people with anxiety disorders, the fear is not temporary and can be overwhelming.

Arsenic Poisoning
Arsenic is a natural element found in soil and minerals. Arsenic compounds are used to preserve wood, as pesticides, and in some industries. Arsenic can get into air, water, and the ground from wind-blown dust. It may also get into water from runoff.

Asthma
Asthma is a chronic disease that affects your airways. Your airways are tubes that carry air in and out of your lungs. If you have asthma, the inside walls of your airways become sore and swollen. That makes them very sensitive, and they may react strongly to things that you are allergic to or find irritating. When your airways react, they get narrower and your lungs get less air.

Atherosclerosis
Atherosclerosis is a disease in which plaque builds up inside your arteries. Plaque is a sticky substance made up of fat, cholesterol, calcium, and other substances found in the blood. Over time, plaque hardens and narrows your arteries. That limits the flow of oxygen-rich blood to your body.

Autism Spectrum Disorder
Autism spectrum disorder (ASD) is a neurological and developmental disorder that begins early in childhood and lasts throughout a person's life. It affects how a person acts and interacts with others, communicates, and learns. It includes what used to be known as Asperger syndrome and pervasive developmental disorders.

B


Binge-eating
Out-of-control eating. People with binge-eating disorder keep eating even after they are full. They often eat until they feel very uncomfortable. Afterward, they usually have feelings of guilt, shame, and distress.

Bipolar Disorder
Bipolar disorder is a serious mental illness. People who have it go through unusual mood changes. They go from very happy, up,and active to very sad and hopeless, down, and inactive, and then back again. They often have normal moods in between. The up feeling is called mania. The down feeling is depression.

Brain Tumors
A brain tumor is a growth of abnormal cells in the tissues of the brain. Brain tumors can be benign, with no cancer cells, or malignant, with cancer cells that grow quickly. Some are primary brain tumors, which start in the brain. Others are metastatic, and they start somewhere else in the body and move to the brain.

Breast Cancer
Breast cancer affects one in eight women during their lives. No one knows why some women get breast cancer, but there are many risk factors.

Breast Tenderness
Premenstrual swelling and tenderness of both breasts occurs during the second half of the menstrual cycle.

Breath Holding Spells
Some children have breath holding spells. This is an involuntary stop in breathing that is not in the child's control.

Breathing Problems
When you're short of breath, it's hard or uncomfortable for you to take in the oxygen your body needs. You may feel as if you're not getting enough air. Sometimes you can have mild breathing problems because of a stuffy nose or intense exercise. But shortness of breath can also be a sign of a serious disease.

Burns
A burn is damage to your body's tissues caused by heat, chemicals, electricity, sunlight, or radiation. Scalds from hot liquids and steam, building fires and flammable liquids and gases are the most common causes of burns. Another kind is an inhalation injury, caused by breathing smoke.

C


Cancer
Cancer begins in your cells, which are the building blocks of your body. Normally, your body forms new cells as you need them, replacing old cells that die. Sometimes this process goes wrong. New cells grow even when you don't need them, and old cells don't die when they should. These extra cells can form a mass called a tumor. Tumors can be benign or malignant. Benign tumors aren't cancer while malignant ones are. Cells from malignant tumors can invade nearby tissues. They can also break away and spread to other parts of the body.

Canker Sores
Canker sores are small, round sores in your mouth. They can be on the inside of your cheek, under your tongue, or in the back of your throat. They usually have a red edge and a gray center. They can be quite painful. They are not the same as cold sores, which are caused by herpes simplex.

Carpal Tunnel Syndrome
You're working at your desk, trying to ignore the tingling or numbness you've had for some time in your hand and wrist. Suddenly, a sharp, piercing pain shoots through the wrist and up your arm. Just a passing cramp? It could be carpal tunnel syndrome.

Cholestasis
Cholestasis is reduction or stoppage of bile flow. Bile is the digestive fluid produced by the liver.

Chronic Fatigue Syndrome
Chronic fatigue syndrome (CFS) is a serious, long-term illness that affects many body systems. Another name for it is myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). CFS can often make you unable to do your usual activities. Sometimes you may not even be able to get out of bed.

Cirrhosis
Cirrhosis is scarring of the liver. Scar tissue forms because of injury or long-term disease. Scar tissue cannot do what healthy liver tissue does - make protein, help fight infections, clean the blood, help digest food and store energy.

Colic and crying
Colic is when a healthy baby cries or fusses frequently for a prolonged period of time. If your baby regularly cries for more than 3 hours a day, he or she may have colic.

Colonic Diseases
Your colon, also known as the large intestine, is part of your digestive system. It's a long, hollow tube at the end of your digestive tract where your body makes and stores stool. Many disorders affect the colon's ability to work properly.

Colorectal Cancer
The colon and rectum are part of the large intestine. Colorectal cancer occurs when tumors form in the lining of the large intestine. It is common in both men and women. The risk of developing colorectal cancer rises after age 50. You're also more likely to get it if you have colorectal polyps, a family history of colorectal cancer, ulcerative colitis or Crohn's disease, eat a diet high in fat, or smoke.

Common Cold
Sneezing, sore throat, a stuffy nose, coughing - everyone knows the symptoms of the common cold. It is probably the most common illness. In the course of a year, people in the United States suffer 1 billion colds.

Constipation
Constipation means that a person has three or fewer bowel movements in a week. The stool can be hard and dry. Sometimes it is painful to pass. At one time or another, almost everyone gets constipated. In most cases, it lasts a short time and is not serious.

COPD
COPD (chronic obstructive pulmonary disease) is a group of lung diseases that make it hard to breathe and get worse over time.

Coronary Artery Disease
Coronary artery disease (CAD) is the most common type of heart disease. It is the leading cause of death in the United States in both men and women.

Cough
Coughing is a reflex that keeps your throat and airways clear. Although it can be annoying, coughing helps your body heal or protect itself. Coughs can be either acute or chronic. Acute coughs begin suddenly and usually last no more than 2 to 3 weeks. Acute coughs are the kind you most often get with a cold, flu, or acute bronchitis. Chronic coughs last longer than 2 to 3 weeks.

Cracked Nipples
Painful cracks on the skin of the nipple and areola. Nipple fissures are common during pregnancy and breast-feeding, but may be caused by friction in some athletes.

Crohns Disease
Crohn's disease causes inflammation of the digestive system. It is one of a group of diseases called inflammatory bowel disease. Crohn's can affect any area from the mouth to the anus. It often affects the lower part of the small intestine called the ileum.

D


Depression
Depression is a serious medical illness. It's more than just a feeling of being sad or 'blue' for a few days. If you are one of the more than 19 million teens and adults in the United States who have depression, the feelings do not go away. They persist and interfere with your everyday life.

Dermatitis
A rash is an area of irritated or swollen skin. Many rashes are itchy, red, painful, and irritated. Some rashes can also lead to blisters or patches of raw skin. Rashes are a symptom of many different medical problems. Other causes include irritating substances and allergies. Certain genes can make people more likely to get rashes.

Diabetes and Pregnancy
Diabetes is a disease in which your blood glucose, or blood sugar, levels are too high. When you are pregnant, high blood sugar levels are not good for your baby.

Diabetes Type 1
With type 1 diabetes, your pancreas does not make insulin. Insulin is a hormone that helps glucose get into your cells to give them energy. Without insulin, too much glucose stays in your blood. Over time, high blood glucose can lead to serious problems with your heart, eyes, kidneys, nerves, and gums and teeth.

Diabetic Nerve Problems
If you have diabetes, your blood glucose, or blood sugar, levels are too high. Over time, this can damage the covering on your nerves or the blood vessels that bring oxygen to your nerves. Damaged nerves may stop sending messages, or may send messages slowly or at the wrong times.

Diarrhea
Diarrhea is loose, watery stools (bowel movements). You have diarrhea if you have loose stools three or more times in one day. Acute diarrhea is diarrhea that lasts a short time. It is a common problem. It usually lasts about one or two days, but it may last longer. Then it goes away on its own.

Diuresis
Osmotic diuresis is increased urination due to the presence of certain substances in the fluid filtered by the kidneys. This fluid eventually becomes urine. These substances cause additional water to come into the urine, increasing its amount.

Dizziness and Vertigo
When you're dizzy, you may feel lightheaded, woozy, or disoriented. If you feel like you or the room are spinning, you have vertigo. These feelings may make you lose your balance.

DNA Damage
DNA damage may be caused by normal cell actions, UV light, some anticancer drugs, and radiation used to treat cancer.

Drug Use and Addiction
Drugs are chemical substances that can change how your body and mind work. They include prescription medicines, over-the-counter medicines, alcohol, tobacco, and illegal drugs.

Dry Eyes
Dry eye happens when your eyes donメt make enough tears to stay wet, or when your tears donメt work correctly. This can make your eyes feel uncomfortable, and in some cases it can also cause vision problems.

Dry Mouth
Dry mouth is the feeling that there is not enough saliva in your mouth. Everyone has a dry mouth once in a while - if they are nervous, upset or under stress. But if you have a dry mouth all or most of the time, it can be uncomfortable and can lead to serious health problems.

Dry skin
Dry skin occurs when your skin loses too much water and oil. Dry skin is common and can affect anyone at any age.

Dysgeusia
People with taste disorders may taste things that aren't there or may not be able to tell the difference in tastes.

E


Edema
Edema means swelling caused by fluid in your body's tissues. It usually occurs in the feet, ankles and legs, but it can involve your entire body.

Enlarged Prostate (BPH)
The prostate is a gland in men. It helps make semen, the fluid that contains sperm. The prostate surrounds the tube that carries urine out of the body. As men age, their prostate grows bigger. If it gets too large, it can cause problems. An enlarged prostate is also called benign prostatic hyperplasia (BPH). Most men will get BPH as they get older. Symptoms often start after age 50.

Erythema
Redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation.

Esophageal spasms
Esophageal spasms are painful contractions within the muscular tube connecting your mouth and stomach (esophagus). Esophageal spasms can feel like sudden, severe chest pain that lasts from a few minutes to hours.

Exercise Capacity (with Heart Conditions)
Cardiovascular exercise is known to be impaired in persons with heart disorders.

Exercise-induced Fatigue
Muscle fatigue is a symptom that decreases your muscles' ability to perform over time. It can be associated with a state of exhaustion, often following strenuous activity or exercise. When you experience fatigue, the force behind your muscles' movements decrease, causing you to feel weaker.

Exercise-Induced Immune Suppression
There is evidence that too much intense exercise can reduce immunity. Research is showing that more than 90 minutes of high-intensity endurance exercise can make athletes susceptible to illness for up to 72 hours after the exercise session.

F


Falls
Falls can be dangerous at any age. Babies and young children can get hurt falling off furniture or down the stairs. Older children may fall off playground equipment. For older adults, falls can be especially serious. They are at higher risk of falling. They are also more likely to fracture (break) a bone when they fall, especially if they have osteoporosis. A broken bone, especially when it is in a hip, may even lead to disability and a loss of independence for older adults.

Fatigue
Everyone feels tired now and then. Sometimes you may just want to stay in bed. But, after a good night's sleep, most people feel refreshed and ready to face a new day. If you continue to feel tired for weeks, it's time to see your doctor. He or she may be able to help you find out what's causing your fatigue and recommend ways to relieve it.

Fatty Liver Disease
Your liver is the largest organ inside your body. It helps your body digest food, store energy, and remove poisons. Fatty liver disease is a condition in which fat builds up in your liver.

Fever
A fever is a body temperature that is higher than normal. A normal temperature can vary from person to person, but it is usually around 98.6 F. A fever is not a disease. It is usually a sign that your body is trying to fight an illness or infection.

Fibromyalgia
Fibromyalgia is chronic condition that causes pain all over the body, fatigue, and other symptoms. People with fibromyalgia may be more sensitive to pain than people who don't have it. This is called abnormal pain perception processing.

Flu
The flu, also called influenza, is a respiratory infection caused by viruses. Each year, millions of Americans get sick with the flu. Sometimes it causes mild illness. But it can also be serious or even deadly, especially for people over 65, newborn babies, and people with certain chronic illnesses.

Fractures
A fracture is a break, usually in a bone. If the broken bone punctures the skin, it is called an open or compound fracture. Fractures commonly happen because of car accidents, falls, or sports injuries. Other causes are low bone density and osteoporosis, which cause weakening of the bones. Overuse can cause stress fractures, which are very small cracks in the bone.

G


Gas
Everyone has gas. Most people pass gas 13 to 21 times a day. Passing gas through the mouth is called belching or burping. Passing gas through the anus is called flatulence. Most of the time gas does not have an odor. The odor comes from bacteria in the large intestine that release small amounts of gases that contain sulfur.

GERD
Your esophagus is the tube that carries food from your mouth to your stomach. Gastroesophageal reflux disease (GERD) happens when a muscle at the end of your esophagus does not close properly. This allows stomach contents to leak back, or reflux, into the esophagus and irritate it.

H


Hair Loss
You lose up to 100 hairs from your scalp every day. That's normal, and in most people, those hairs grow back. But many men -- and some women -- lose hair as they grow older. You can also lose your hair if you have certain diseases, such as thyroid problems, diabetes, or lupus. If you take certain medicines or have chemotherapy for cancer, you may also lose your hair. Other causes are stress, a low protein diet, a family history, or poor nutrition.

Headache
Almost everyone has had a headache. Headache is the most common form of pain. It's a major reason people miss days at work or school or visit the doctor.

Heart Attack
Each year almost 800,000 Americans have a heart attack. A heart attack happens when blood flow to the heart suddenly becomes blocked. Without the blood coming in, the heart can't get oxygen. If not treated quickly, the heart muscle begins to die. But if you do get quick treatment, you may be able to prevent or limit damage to the heart muscle. That's why it's important to know the symptoms of a heart attack and call 911 if you or someone else is having them. You should call, even if you are not sure that it is a heart attack.

Heart Failure
Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped or is about to stop working. It means that your heart is not able to pump blood the way it should. It can affect one or both sides of the heart.

Heartburn
Heartburn is a painful burning feeling in your chest or throat. It happens when stomach acid backs up into your esophagus, the tube that carries food from your mouth to your stomach.

Hemorrhoids
Hemorrhoids are swollen, inflamed veins around the anus or lower rectum. They are either inside the anus or under the skin around the anus. They often result from straining to have a bowel movement. Other factors include pregnancy, aging and chronic constipation or diarrhea.

Hepatic Encephalopathy
When your liver is damaged it can no longer remove toxic substances from your blood. These toxins build up and can travel through your body until they reach your brain, causing mental and physical symptoms of HE.

Hepatopulmonary Syndrome
When the liver is not functioning properly, blood vessels in the lungs may dilate. If this is severe enough, the lungs can lose their ability to effectively transfer oxygen to the body.

Hirsutism
The main symptom of hirsutism is unwanted hair growth on a womanメs face, chest, and back. This thick, dark hair is different from the normal, fine モbabyヤ hair on other parts of the body.

HIV/AIDS
HIV stands for human immunodeficiency virus. It harms your immune system by destroying the white blood cells that fight infection. This puts you at risk for serious infections and certain cancers. AIDS stands for acquired immunodeficiency syndrome. It is the final stage of infection with HIV. Not everyone with HIV develops AIDS.

Hyperthyroidism
Hyperthyroidism, or overactive thyroid, happens when your thyroid gland makes more thyroid hormones than your body needs.

I


Immune System and Disorders
Your immune system is a complex network of cells, tissues, and organs that work together to defend against germs. It helps your body to recognize these foreign invaders. Then its job is to keep them out, or if it can't, to find and destroy them.

Inflammation
Inflammation is the response of immune cells to tissue damage, pathogens, and other intrusions, with the purpose of healing and restoring cells. It's a vital process, but when itメs excessive or prolonged, it causes pain, damage tissues, and disrupt physiological functions, thereby leading to many health issues.

Injury
An injury is damage to your body. It is a general term that refers to harm caused by accidents, falls, hits, weapons, and more. In the U.S., millions of people injure themselves every year. These injuries range from minor to life-threatening. Injuries can happen at work or play, indoors or outdoors, driving a car, or walking across the street.

Insomnia
Insomnia is a common sleep disorder. If you have it, you may have trouble falling asleep, staying asleep, or both. As a result, you may get too little sleep or have poor-quality sleep. You may not feel refreshed when you wake up.

Intermittent Claudication
Claudication is pain caused by too little blood flow to muscles during exercise. Most often this pain occurs in the legs after walking at a certain pace and for a certain amount of time ラ depending on the severity of the condition.

Intraocular Pressure
It is the pressure within an eye that is elevated in instances of retinal disorders such as glaucoma, and contributes to the pathology.

Irritability
Feelings of frustration or anger, often over seemingly small matters.

Irritable Bowel Syndrome
Irritable bowel syndrome (IBS) is a problem that affects the large intestine. It can cause abdominal cramping, bloating, and a change in bowel habits. Some people with the disorder have constipation. Some have diarrhea. Others go back and forth between the two. Although IBS can cause a great deal of discomfort, it does not harm the intestines.

Itching
Itching is an irritating sensation that makes you want to scratch your skin. Sometimes it can feel like pain, but it is different. Often, you feel itchy in one area in your body, but sometimes you may feel itching all over. Along with the itching, you may also have a rash or hives.

J


Jet Lag
Your body has its own internal clock, or circadian rhythms, that signals your body when to stay awake and when to sleep. Jet lag occurs because your body's clock is still synced to your original time zone, instead of to the time zone where you've traveled. The more time zones crossed, the more likely you are to experience jet lag.

Joint pain
Joint pain can be caused by many types of injuries or conditions. It may be linked to arthritis, bursitis, and muscle pain. No matter what causes it, joint pain can be very bothersome.

K


Kashin-Beck Disease
Selenium deficiency can cause Kashin-Beck disease, a type of arthritis that produces pain, swelling, and loss of motion in your joints.

Kidney Stones
A kidney stone is a solid piece of material that forms in the kidney from substances in the urine. It may be as small as a grain of sand or as large as a pearl. Most kidney stones pass out of the body without help from a doctor. But sometimes a stone will not go away. It may get stuck in the urinary tract, block the flow of urine and cause great pain.

L


Lead Poisoning
Lead is a metal that occurs naturally in the earth's crust. Lead can be found in all parts of our environment. Much of it comes from human activities such as mining and manufacturing. Lead used to be in paint; older houses may still have lead paint.

Liver Cancer
Your liver is the largest organ inside your body. It helps your body digest food, store energy, and remove poisons. Primary liver cancer starts in the liver. Metastatic liver cancer starts somewhere else and spreads to your liver.

Liver Damage
Symptoms of liver disease can vary, but they often include swelling of the abdomen and legs, bruising easily, changes in the color of your stool and urine, and jaundice, or yellowing of the skin and eyes.

Lung Cancer
Lung cancer is one of the most common cancers in the world. It is a leading cause of cancer death in men and women in the United States. Cigarette smoking causes most lung cancers. The more cigarettes you smoke per day and the earlier you started smoking, the greater your risk of lung cancer. High levels of pollution, radiation and asbestos exposure may also increase risk.

Lupus
Lupus is an autoimmune disease. This means that your immune system attacks healthy cells and tissues by mistake. This can damage many parts of the body, including the joints, skin, kidneys, heart, lungs, blood vessels, and brain.

M


Melasma
Melasma is a common skin problem. It causes brown to gray-brown patches, usually on the face. Most people get it on their cheeks, bridge of their nose, forehead, chin, and above their upper lip. It also can appear on other parts of the body that get lots of sun, such as the forearms and neck.

Memory
Every day, you have different experiences and you learn new things. Your brain cannot store all of that information, so it has to decide what is worth remembering. Memory is the process of storing and then remembering this information. There are different types of memory. Short-term memory stores information for a few seconds or minutes. Long-term memory stores it for a longer period of time.

Menopause
Menopause is the time in a woman's life when her period stops. It usually occurs naturally, most often after age 45. Menopause happens because the woman's ovaries stop producing the hormones estrogen and progesterone.

Migraine
Migraines are a recurring type of headache. They cause moderate to severe pain that is throbbing or pulsing. The pain is often on one side of your head. You may also have other symptoms, such as nausea and weakness. You may be sensitive to light and sound.

Mild Cognitive Impairment
Some forgetfulness can be a normal part of aging. However, some people have more memory problems than other people their age. This condition is called mild cognitive impairment, or MCI. People with MCI can take care of themselves and do their normal activities.

Mitral Regurgitation
Mitral regurgitation (MR), which is also known as mitral insufficiency, is a common heart valve disorder. When MR is present, blood leaks backwards through the mitral valve when the heart contracts. This reduces the amount of blood that is pumped out to the body.

Mucositis
Oral mucositis is tissue swelling in the mouth. Radiation therapy or chemotherapy may cause mucositis.

Multiple Sclerosis
Multiple sclerosis (MS) is a nervous system disease that affects your brain and spinal cord. It damages the myelin sheath, the material that surrounds and protects your nerve cells. This damage slows down or blocks messages between your brain and your body, leading to the symptoms of MS.

Muscle Cramps
Muscle cramps are sudden, involuntary contractions or spasms in one or more of your muscles. They are very common and often occur after exercise. Some people get muscle cramps, especially leg cramps, at night. They can be painful, and they may last a few seconds to several minutes.

Muscle Soreness
Muscle aches and pains are common and can involve more than one muscle. Muscle pain also can involve ligaments, tendons, and fascia. Fascias are the soft tissues that connect muscles, bones, and organs.

Muscular Dystrophy
Muscular dystrophy (MD) is a group of more than 30 inherited diseases. They all cause muscle weakness and muscle loss. Some forms of MD appear in infancy or childhood. Others may not appear until middle age or later. The different types can vary in whom they affect, which muscles they affect, and what the symptoms are. All forms of MD grow worse as the person's muscles get weaker. Most people with MD eventually lose the ability to walk.

Myotonic Dystrophy
Myotonic dystrophy is an inherited type of muscular dystrophy that affects the muscles and other body systems. People who have myotonic dystrophy have muscle wasting and weakness in their lower legs, hands, neck and face that get worse over time.

O


Obsessive-Compulsive Disorder
Obsessive-compulsive disorder (OCD) is a mental disorder in which you have thoughts (obsessions) and rituals (compulsions) over and over. They interfere with your life, but you cannot control or stop them.

Oral Cancer
Oral cancer can form in any part of the mouth. Most oral cancers begin in the flat cells that cover the surfaces of your mouth, tongue, and lips. Anyone can get oral cancer, but the risk is higher if you are male, use tobacco, drink lots of alcohol, have HPV, or have a history of head or neck cancer. Frequent sun exposure is also a risk factor for lip cancer.

Orthostatic Hypotension
Orthostatic hypotension is a sudden fall in blood pressure that occurs when a person assumes a standing position. It is due to a lesion of the baroreflex loop, which senses a change in blood pressure and adjusts heart rate and activates sympathetic nerve system fibers to cause the blood vessels to narrow and correct blood pressure.

Osteoarthritis
Osteoarthritis is the most common form of arthritis. It causes pain, swelling, and reduced motion in your joints. It can occur in any joint, but usually it affects your hands, knees, hips or spine.

Ovarian Cancer
The ovaries are part of the female reproductive system. They produce a woman's eggs and female hormones. Each ovary is about the size and shape of an almond.

Oxidative Damage
Oxidative damage is the harm sustained by cells and tissues that are unable to keep up with free radical production.

P


Pain
Pain is a signal in your nervous system that something may be wrong. It is an unpleasant feeling, such as a prick, tingle, sting, burn, or ache. Pain may be sharp or dull. It may come and go, or it may be constant. You may feel pain in one area of your body, such as your back, abdomen, chest, pelvis, or you may feel pain all over.

Pancreatic Cancer
The pancreas is a gland behind your stomach and in front of your spine. It produces the juices that help break down food and the hormones that help control blood sugar levels. Pancreatic cancer usually begins in the cells that produce the juices.

Panic Disorder
Panic disorder is a type of anxiety disorder. It causes panic attacks, which are sudden feelings of terror when there is no real danger. You may feel as if you are losing control.

Parasitic Diseases
Parasites are living things that use other living things - like your body - for food and a place to live. You can get them from contaminated food or water, a bug bite, or sexual contact. Some parasitic diseases are easily treated and some are not.

Parkinson's Disease
Parkinson's disease (PD) is a type of movement disorder. It happens when nerve cells in the brain don't produce enough of a brain chemical called dopamine. Sometimes it is genetic, but most cases do not seem to run in families. Exposure to chemicals in the environment might play a role.

Peptic Ulcer
A peptic ulcer is a sore in the lining of your stomach or your duodenum, the first part of your small intestine. A burning stomach pain is the most common symptom.

Period Pain
Menstruation, or period, is normal vaginal bleeding that happens as part of a woman's monthly cycle. Many women have painful periods, also called dysmenorrhea. The pain is most often menstrual cramps, which are a throbbing, cramping pain in your lower abdomen. You may also have other symptoms, such as lower back pain, nausea, diarrhea, and headaches. Period pain is not the same as premenstrual syndrome (PMS). PMS causes many different symptoms, including weight gain, bloating, irritability, and fatigue. PMS often starts one to two weeks before your period starts.

Peripheral Arterial Disease
Peripheral arterial disease (PAD) happens when there is a narrowing of the blood vessels outside of your heart. The cause of PAD is atherosclerosis. This happens when plaque builds up on the walls of the arteries that supply blood to the arms and legs. Plaque is a substance made up of fat and cholesterol. It causes the arteries to narrow or become blocked. This can reduce or stop blood flow, usually to the legs. If severe enough, blocked blood flow can cause tissue death and can sometimes lead to amputation of the foot or leg.

Peyronie's Disease
Bending of the penis during an erection due to a hard lump called a plaque.

Phobias
A phobia is a type of anxiety disorder. It is a strong, irrational fear of something that poses little or no real danger.

Pinkeye
Conjunctivitis is the medical name for pink eye. It involves inflammation of the outer layer of the eye and inside of the eyelid. It can cause swelling, itching, burning, discharge, and redness.

Polycystic Ovary Syndrome
Polycystic ovary syndrome (PCOS) happens when a woman's ovaries or adrenal glands produce more male hormones than normal. PCOS causes cysts (fluid-filled sacs) to grow on the ovaries.

Post-Traumatic Stress Disorder
Post-traumatic stress disorder (PTSD) is a mental health disorder that some people develop after they experience or see a traumatic event. The traumatic event may be life-threatening, such as combat, a natural disaster, a car accident, or sexual assault. But sometimes the event is not necessarily a dangerous one. For example, the sudden, unexpected death of a loved one can also cause PTSD.

Prader-Willi Syndrome
Prader-Willi Syndrome (PWS) is a rare genetic disorder. It causes poor muscle tone, low levels of sex hormones and a constant feeling of hunger. The part of the brain that controls feelings of fullness or hunger does not work properly in people with PWS. They overeat, leading to obesity.

Pre-Eclampsia
Is a sudden increase in blood pressure after the 20th week of pregnancy. It usually happens in the last trimester. In rare cases, symptoms may not start until after delivery. This is called postpartum preeclampsia. Preeclampsia also includes signs of damage to some of your organs, such as your liver or kidney. The signs may include protein in the urine and very high blood pressure. Preeclampsia can be serious or even life-threatening for both you and your baby.

Premenstrual Syndrome
Premenstrual syndrome, or PMS, is a group of symptoms that start one to two weeks before your period. Most women have at least some symptoms of PMS, and the symptoms go away after their periods start. For some women, the symptoms are severe enough to interfere with their lives. They have a type of PMS called premenstrual dysphoric disorder, or PMDD.

Prostate Cancer
The prostate is the gland below a man's bladder that produces fluid for semen. Prostate cancer is common among older men. It is rare in men younger than 40. Risk factors for developing prostate cancer include being over 65 years of age, family history, and being African American.

Proteinuria
If there is a problem with your kidneys, protein can leak into your urine. While a small amount is normal, a large amount of protein in urine may indicate kidney disease.

Psoriasis
Psoriasis is a skin disease that causes itchy or sore patches of thick, red skin with silvery scales. You usually get the patches on your elbows, knees, scalp, back, face, palms and feet, but they can show up on other parts of your body. Some people who have psoriasis also get a form of arthritis called psoriatic arthritis.

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Rashes
A rash is an area of irritated or swollen skin. Many rashes are itchy, red, painful, and irritated. Some rashes can also lead to blisters or patches of raw skin. Rashes are a symptom of many different medical problems. Other causes include irritating substances and allergies. Certain genes can make people more likely to get rashes.

Restless Legs
Restless legs syndrome (RLS) causes a powerful urge to move your legs. Your legs become uncomfortable when you are lying down or sitting. Some people describe it as a creeping, crawling, tingling, or burning sensation. Moving makes your legs feel better, but not for long. RLS can make it hard to fall asleep and stay asleep.

Rheumatoid Arthritis
Rheumatoid arthritis (RA) is a form of arthritis that causes pain, swelling, stiffness and loss of function in your joints. It can affect any joint but is common in the wrist and fingers.

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Scabies
Scabies is an itchy skin condition caused by the microscopic mite Sarcoptes scabei. It is common all over the world, and can affect anyone. Scabies spreads quickly in crowded conditions where there is frequent skin-to-skin contact between people. Hospitals, child-care centers, and nursing homes are examples. Scabies can easily infect sex partners and other household members. Sharing clothes, towels, and bedding can sometimes spread scabies. This can happen much more easily when the infested person has crusted scabies. You cannot get scabies from a pet. Pets get a different mite infection called mange.

Schizophrenia
Schizophrenia is a serious brain illness. People who have it may hear voices that aren't there. They may think other people are trying to hurt them. Sometimes they don't make sense when they talk. The disorder makes it hard for them to keep a job or take care of themselves.

Seizures
Seizures are symptoms of a brain problem. They happen because of sudden, abnormal electrical activity in the brain. When people think of seizures, they often think of convulsions in which a person's body shakes rapidly and uncontrollably. Not all seizures cause convulsions. There are many types of seizures and some have mild symptoms. Seizures fall into two main groups. Focal seizures, also called partial seizures, happen in just one part of the brain. Generalized seizures are a result of abnormal activity on both sides of the brain.

Sinusitis
Sinusitis means your sinuses are inflamed. The cause can be an infection or another problem. Your sinuses are hollow air spaces within the bones surrounding the nose. They produce mucus, which drains into the nose. If your nose is swollen, this can block the sinuses and cause pain.

Skin Aging
Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it less plump and smooth. It might take longer to heal, too.

Sleep Deprivation
Is a condition that occurs if you don't get enough sleep. Sleep deficiency is a broader concept.

Sleep Terrors
Sleep terrors are episodes of screaming, intense fear and flailing while still asleep. Also known as night terrors, sleep terrors often are paired with sleepwalking. Like sleepwalking, sleep terrors are considered a parasomnia, an undesired occurrence during sleep. A sleep terror episode usually lasts from seconds to a few minutes, but episodes may last longer.

Smoking
There's no way around it; smoking is bad for your health. It harms nearly every organ of the body, some that you would not expect. Cigarette smoking causes nearly one in five deaths in the United States. It can also cause many other cancers and health problems.

Stress
Everyone feels stressed from time to time. Not all stress is bad. All animals have a stress response, and it can be life-saving. But chronic stress can cause both physical and mental harm.

Stroke
A stroke happens when there is a loss of blood flow to part of the brain. Your brain cells cannot get the oxygen and nutrients they need from blood, and they start to die within a few minutes. This can cause lasting brain damage, long-term disability, or even death.

Sudden Infant Death Syndrome
Sudden infant death syndrome (SIDS) is the sudden, unexplained death of an infant younger than one year old. Some people call SIDS 'crib death' because many babies who die of SIDS are found in their cribs.

Sun Exposure
Ultraviolet (UV) rays are an invisible form of radiation. They can pass through your skin and damage your skin cells. Sunburns are a sign of skin damage. Suntans aren't healthy, either. They appear after the sun's rays have already killed some cells and damaged others. UV rays can cause skin damage during any season or at any temperature. They can also cause eye problems, wrinkles, skin spots, and skin cancer.

Superficial Thrombophlebitis
Thrombophlebitis is a swollen or inflamed vein due to a blood clot. Superficial refers to veins just below the skin's surface.

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Tardive Dyskinesia
Tardive dyskinesia is a neurological syndrome caused by the long-term use of neuroleptic drugs. Neuroleptic drugs are generally prescribed for psychiatric disorders, as well as for some gastrointestinal and neurological disorders. Tardive dyskinesia is characterized by repetitive, involuntary, purposeless movements. Features of the disorder may include grimacing, tongue protrusion, lip smacking, puckering and pursing, and rapid eye blinking. Rapid movements of the arms, legs, and trunk may also occur. Involuntary movements of the fingers may be present.

Thromboembolism
Deep vein thrombosis, or DVT, is a blood clot that forms in a vein deep in the body. Most deep vein clots occur in the lower leg or thigh. If the vein swells, the condition is called thrombophlebitis. A deep vein thrombosis can break loose and cause a serious problem in the lung, called a pulmonary embolism.

Tinnitus
Tinnitus is often described as a ringing in the ears. It also can sound like roaring, clicking, hissing, or buzzing. It may be soft or loud, high pitched or low pitched. You might hear it in either one or both ears.

Tonsillitis
Tonsils are lumps of tissue at the back of the throat. There are two of them, one on each side. Along with the adenoids, tonsils are part of the lymphatic system. The lymphatic system clears away infection and keeps body fluids in balance. Tonsils and adenoids work by trapping the germs coming in through the mouth and nose.

Traumatic Brain Injury
Traumatic brain injury (TBI) is a sudden injury that causes damage to the brain. It may happen when there is a blow, bump, or jolt to the head. This is a closed head injury. A TBI can also happen when an object penetrates the skull. This is a penetrating injury.

Trichotillomania
People with trichotillomania pull hair on various parts of their bodies, including the scalp, face, arms, legs and pubic areas. They may not notice the hair pulling until they need to cover up bald patches with hair clips, a hat, wig or scarf. People with trichotillomania are not able stop pulling their hair.

Tuberculosis
Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis. The bacteria usually attack the lungs, but they can also damage other parts of the body.

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Ulcerative Colitis
Ulcerative colitis (UC) is a disease that causes inflammation and sores, called ulcers, in the lining of the rectum and colon. It is one of a group of diseases called inflammatory bowel disease.

Urinary Incontinence
Urinary incontinence (UI) is loss of bladder control. Symptoms can range from mild leaking to uncontrollable wetting. It can happen to anyone, but it becomes more common with age. Women experience UI twice as often as men.

Urinary Tract Infections
The urinary system is the body's drainage system for removing wastes and extra water. It includes two kidneys, two ureters, a bladder, and a urethra. Urinary tract infections (UTIs) are the second most common type of infection in the body.

Urine and Urination
Your kidneys make urine by filtering wastes and extra water from your blood. The waste is called urea. Your blood carries it to the kidneys. From the kidneys, urine travels down two thin tubes called ureters to the bladder. The bladder stores urine until you are ready to urinate. It swells into a round shape when it is full and gets smaller when empty. If your urinary system is healthy, your bladder can hold up to 16 ounces (2 cups) of urine comfortably for 2 to 5 hours.

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Vaginal Dryness
Vaginal dryness is present when the tissues of the vagina are not well-lubricated and healthy.

Vaginitis
Vaginitis, also called vulvovaginitis, is an inflammation or infection of the vagina. It can also affect the vulva, which is the external part of a woman's genitals. Vaginitis can cause itching, pain, discharge, and odor.

Varicose Veins
Varicose veins are swollen, twisted veins that you can see just under the skin. They usually occur in the legs, but also can form in other parts of the body. Hemorrhoids are a type of varicose vein.

Vascular Diseases
Your vascular system is your body's network of blood vessels.

Viral Infections
Viruses are very tiny germs. They are made of genetic material inside of a protein coating. Viruses cause familiar infectious diseases such as the common cold, flu and warts. They also cause severe illnesses such as HIV/AIDS, smallpox, and Ebola.

Vitiligo
Vitiligo causes white patches on your skin. It can also affect your eyes, mouth, and nose. It occurs when the cells that give your skin its color are destroyed. No one knows what destroys them. It is more common in people with autoimmune diseases, and it might run in families. It usually starts before age 40.