Health, as defined by the World Health Organization (WHO), is "a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity." This definition has been subject to controversy, as it may have limited value for implementation. Health may be defined as the ability to adapt and manage physical, mental and social challenges throughout life.
Selected general articles
(also foodborne disease
and colloquially referred to as food poisoning
) is any illness
resulting from the food spoilage of contaminated food
, pathogenic bacteria
, or parasites
that contaminate food, as well as toxins
such as poisonous mushrooms
and various species of beans that have not been boiled
for at least 10 minutes.
Symptoms vary depending on the cause, and are described below in this article. A few broad generalizations can be made, e.g.: the incubation period
ranges from hours to days, depending on the cause and on how much was consumed. The incubation period tends to cause sufferers to not associate the symptoms with the item consumed, and so to cause sufferers to attribute the symptoms to gastroenteritis
Symptoms often include vomiting, fever, and aches, and may include diarrhea. Bouts of vomiting can be repeated with an extended delay in between, because even if infected food was eliminated from the stomach in the first bout, microbes
, like bacteria
, (if applicable) can pass through the stomach
into the intestine
and begin to multiply. Some types of microbes stay in the intestine, some produce a toxin
that is absorbed into the bloodstream
, and some can directly invade deeper body tissues. Read more...
, also known as Dental and Oral Medicine
, is a branch of medicine
that consists of the study, diagnosis
, prevention, and treatment of diseases
, disorders, and conditions of the oral cavity
, commonly in the dentition
but also the oral mucosa
, and of adjacent and related structures and tissues, particularly in the maxillofacial (jaw and facial) area. Although primarily associated with teeth
among the general public, the field of dentistry or dental medicine is not limited to teeth but includes other aspects of the craniofacial
complex including the temporomandibular joint
and other supporting, muscular, lymphatic, nervous, vascular, and anatomical structures.
Dentistry is often also understood to subsume the now largely defunct medical specialty
(the study of the mouth and its disorders and diseases) for which reason the two terms are used interchangeably in certain regions.
Dental treatments are carried out by a dental team, which often consists of a dentist
and dental auxiliaries
, dental hygienists
, dental technicians
, as well as dental therapists
). Most dentists either work in private practices (primary care
), dental hospitals or (secondary care
) institutions (prisons, armed forces bases, etc.). Read more...
is a condition that results from eating a diet
in which one or more nutrients
are either not enough or are too much such that the diet causes health problems. It may involve calories
. Not enough nutrients is called undernutrition
while too much is called overnutrition
. Malnutrition is often used to specifically refer to undernutrition where an individual is not getting enough calories, protein, or micronutrients
. If undernutrition occurs during pregnancy
, or before two years of age, it may result in permanent problems with physical and mental development. Extreme undernourishment, known as starvation
, may have symptoms that include: a short height, thin body, very poor energy levels, and swollen legs and abdomen
. People also often get infections and are frequently cold
. The symptoms of micronutrient deficiencies
depend on the micronutrient that is lacking.
Undernourishment is most often due to not enough high-quality food being available to eat. This is often related to high food prices and poverty
. A lack of breastfeeding
may contribute, as may a number of infectious diseases
such as: gastroenteritis
, and measles
, which increase nutrient requirements. There are two main types of undernutrition: protein-energy malnutrition
and dietary deficiencies. Protein-energy malnutrition has two severe forms: marasmus
(a lack of protein and calories) and kwashiorkor
(a lack of just protein). Common micronutrient deficiencies include: a lack of iron
, and vitamin A
. During pregnancy
, due to the body's increased need, deficiencies may become more common. In some developing countries
, overnutrition in the form of obesity
is beginning to present within the same communities as undernutrition. Other causes of malnutrition include anorexia nervosa
and bariatric surgery
Efforts to improve nutrition
are some of the most effective forms of development aid
. Breastfeeding can reduce rates of malnutrition and death in children, and efforts to promote the practice increase the rates of breastfeeding. In young children, providing food (in addition to breastmilk) between six months and two years of age improves outcomes. There is also good evidence supporting the supplementation
of a number of micronutrients to women during pregnancy and among young children in the developing world. To get food to people who need it most, both delivering food and providing money so people can buy food within local markets are effective. Simply feeding students at school is insufficient. Management of severe malnutrition within the person's home with ready-to-use therapeutic foods
is possible much of the time. In those who have severe malnutrition complicated by other health problems, treatment in a hospital setting is recommended. This often involves managing low blood sugar
and body temperature
, addressing dehydration
, and gradual feeding. Routine antibiotics
are usually recommended due to the high risk of infection. Longer-term measures include: improving agricultural practices, reducing poverty, improving sanitation
, and the empowerment of women
. Read more...
, or geriatric medicine
, is a specialty that focuses on health care of elderly people
. It aims to promote health
and treating diseases
in older adults
. There is no set age at which patients may be under the care of a geriatrician
, or geriatric physician
, a physician who specializes in the care of elderly people. Rather, this decision is determined by the individual patient's needs, and the availability of a specialist. It is important to note the difference between geriatrics, the care of aged people, and gerontology
, which is the study of the aging
process itself. The term geriatrics
comes from the Greek
meaning "old man", and ιατρός iatros
meaning "healer". However, geriatrics is sometimes called medical gerontology
. Read more...
or general medicine
nations) is the medical specialty
dealing with the prevention, diagnosis, and treatment of adult diseases. Physicians specializing in internal medicine are called internists
, or physicians
(without a modifier) in Commonwealth nations. Internists are skilled in the management of patients who have undifferentiated or multi-system disease
processes. Internists care for hospitalized and ambulatory patients and may play a major role in teaching and research.
Because internal medicine patients are often seriously ill or require complex investigations, internists do much of their work in hospitals
. Internists often have subspecialty interests in diseases affecting particular organs or organ systems.
Internal medicine is also a specialty within clinical pharmacy
and veterinary medicine
. Read more...
, or caloric restriction
, or energy restriction
, is a dietary regimen
that reduces calorie
intake without incurring malnutrition
or a reduction in essential nutrients
. "Reduce" can be defined relative to the subject's previous intake before intentionally restricting calories, or relative to an average person of similar body type. Commonly consumed food components containing calories are carbohydrates
In preliminary research, some non-human species on calorie restriction diets without malnutrition may exhibit slowing of the biological aging process
, resulting in an increase in both median
and maximum lifespan
, but this effect is not universal. In humans, the long-term health effects of moderate caloric restriction with sufficient nutrients are unknown. Read more...
Tobacco smoking Marlboro
's package of the ice blast cigarette
is the practice of smoking tobacco
and inhaling tobacco smoke
(consisting of particle and gaseous phases). (A more broad definition may include simply taking tobacco smoke into the mouth, and then releasing it, as is done by some with tobacco pipes
.) The practice is believed to have begun as early as 5000–3000 BC in Mesoamerica
and South America
. Tobacco was introduced to Eurasia
in the late 17th century by European colonists
, where it followed common trade routes. The practice encountered criticism from its first import into the Western world
onwards but embedded itself in certain strata of a number of societies before becoming widespread upon the introduction of automated cigarette
German scientists identified a link between smoking and lung cancer
in the late 1920s, leading to the first anti-smoking campaign
in modern history, albeit one truncated by the collapse
of Nazi Germany
at the end of World War II
. In 1950, British researchers demonstrated a clear relationship between smoking and cancer. Evidence continued to mount in the 1980s, which prompted political action against the practice. Rates of consumption since 1965 in the developed world
have either peaked or declined. However, they continue to climb in the developing world
Smoking is the most common method of consuming tobacco, and tobacco is the most common substance smoked. The agricultural product is often mixed with additives and then combusted
. The resulting smoke is then inhaled and the active substances absorbed through the alveoli in the lungs
or the oral mucosa
. Combustion was traditionally enhanced by addition of potassium
. Many substances in cigarette smoke trigger chemical reactions in nerve endings, which heighten heart rate, alertness and reaction time, among other things. Dopamine
are released, which are often associated with pleasure. As of 2008 to 2010, tobacco is used by about 49% of men and 11% of women aged 15 or older in fourteen low-income and middle-income countries (Bangladesh, Brazil, China, Egypt, India, Mexico, Philippines, Poland, Russia, Thailand, Turkey, Ukraine, Uruguay and Vietnam), with about 80% of this usage in the form of smoking. The gender gap tends to be less pronounced in lower age groups. Read more...
Mouse (right) with spinal muscular atrophy
is the partial or complete wasting
away of a part of the body. Causes of atrophy include mutations
(which can destroy the gene to build up the organ), poor nourishment, poor circulation
, loss of hormonal
support, loss of nerve
supply to the target organ
, excessive amount of apoptosis
of cells, and disuse or lack of exercise
or disease intrinsic to the tissue itself. In medical practice, hormonal and nerve inputs that maintain an organ or body part are said to have trophic
effects. A diminished muscular trophic condition is designated as atrophy
. Atrophy is reduction in size of cell, organ or tissue, after attaining its normal mature growth. In contrast, hypoplasia is the reduction in size of a cell, organ, or tissue that has not attained normal maturity.
Atrophy is the general physiological
process of reabsorption and breakdown of tissues
, involving apoptosis. When it occurs as a result of disease or loss of trophic support due to other diseases, it is termed pathological atrophy
, although it can be a part of normal body development and homeostasis
as well. Read more...
A 2007 assessment of harm from recreational drug use (mean physical harm and mean dependence liability)
, also known as drug abuse
, is a patterned use of a drug in which the user consumes the substance in amounts or with methods which are harmful to themselves or others, and is a form of substance-related disorder
. Widely differing definitions of drug abuse are used in public health, medical and criminal justice contexts. In some cases criminal or anti-social behaviour
occurs when the person is under the influence of a drug, and long term personality changes in individuals may occur as well. In addition to possible physical, social, and psychological harm, use of some drugs may also lead to criminal penalties, although these vary widely depending on the local jurisdiction.
Drugs most often associated with this term include: alcohol
and some substituted amphetamines
. The exact cause of substance abuse is not clear, with the two predominant theories being: either a genetic disposition which is learned from others, or a habit which if addiction develops, manifests itself as a chronic debilitating disease.
In 2010 about 5% of people (230 million) used an illicit substance. Of these 27 million have high-risk drug use otherwise known as recurrent drug use causing harm to their health, psychological problems, or social problems that put them at risk of those dangers. In 2015 substance use disorders resulted in 307,400 deaths, up from 165,000 deaths in 1990. Of these, the highest numbers are from alcohol use disorders
at 137,500, opioid use disorders
at 122,100 deaths, amphetamine use disorders
at 12,200 deaths, and cocaine use disorders
at 11,100. Read more...
is a field of expertise practiced by a clinician
known as a speech-language pathologist
). or a speech therapist
. SLP is considered a "related health profession" or "allied health profession" along with audiology
, occupational therapy
, clinical psychology
, physical therapy
, and others. The field of SLP is distinguished from other "related health professions" as SLPs are legally permitted to engage in certain disorders which fall within their scope of practice.
SLPs specialize in the evaluation, diagnosis, and treatment of communication disorders
and language disorders
), cognitive-communication disorders, voice disorders
, and swallowing disorders
. SLPs also play an important role in the diagnosis and treatment of autism spectrum disorder
(often in a team with pediatricians and psychologists).
A common misconception is that speech-language pathology is restricted to adjusting a speaker's speech sound articulation to meet the expected normal pronunciation, such as helping English speaking individuals enunciate the traditionally difficult "r". SLPs can also often help people who stutter to speak more fluently. Articulation and fluency however are only two facets of the work of an SLP. In fact, speech-language pathology is concerned with a broad scope of speech, language, swallowing, and voice issues involved in communication, some of which include: Read more...
is the science
and practice of establishing the diagnosis
, and prevention
. Medicine encompasses a variety of health care
practices evolved to maintain and restore health
by the prevention
. Contemporary medicine applies biomedical sciences
, biomedical research
, and medical technology
, treat, and prevent injury and disease, typically through pharmaceuticals
, but also through therapies as diverse as psychotherapy
, external splints and traction
, medical devices
, and ionizing radiation
, amongst others.
Medicine has been around for thousands of years, during most of which it was an art (an area of skill and knowledge) frequently having connections to the religious
beliefs of local culture. For example, a medicine man
would apply herbs and say prayers
for healing, or an ancient philosopher and physician
would apply bloodletting
according to the theories of humorism
. In recent centuries, since the advent of modern science
, most medicine has become a combination of art and science (both basic
, under the umbrella
of medical science
). While stitching technique for sutures
is an art learned through practice, the knowledge of what happens at the cellular
level in the tissues being stitched arises through science.
Prescientific forms of medicine are now known as traditional medicine
and folk medicine
. They remain commonly used with or instead of scientific medicine and are thus called alternative medicine
. For example, evidence on the effectiveness of acupuncture
is "variable and inconsistent" for any condition, but is generally safe when done by an appropriately trained practitioner. In contrast, treatments outside the bounds of safety and efficacy are termed quackery
. Read more...
is the science
that interprets the interaction of nutrients
and other substances in food
in relation to maintenance, growth, reproduction, health
and disease of an organism. It includes food intake, absorption
, and excretion
of an organism is what it eats, which is largely determined by the availability and palatability
of foods. For humans, a healthy diet
includes preparation of food
and storage methods that preserve nutrients from oxidation, heat or leaching, and that reduce risk of foodborne illnesses
In humans, an unhealthy diet can cause deficiency-related diseases such as blindness
, preterm birth
, or nutrient excess health-threatening conditions such as obesity
and metabolic syndrome
; and such common chronic systemic diseases as cardiovascular disease
, and osteoporosis
. Undernutrition can lead to wasting
in acute cases, and the stunting
in chronic cases of malnutrition
. Read more...
Did you know...
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For editor resources and to collaborate with other editors on improving Wikipedia's Health-related articles, see WikiProject Health.
Calcium combined with vitamin D (as calciferol) supplement tablets with fillers.
Percentage of obese population in 2010, Data source: OECD's iLibrary.
A bottle of B-complex vitamin pills
A woman jogging at a beach in the U.S. to maintain/improve her physical fitness
Postage stamp, New Zealand, 1933. Public health has been promoted – and depicted – in a wide variety of ways.
Running has become a popular form of exercise.
A lady washing her hands c. 1655
Hippocrates lived about 400 BC, and Galen and the understanding of nutrition followed him for centuries.
An astronaut, Daniel Tani, working out with a short bar to increase his upper body strength while in a microgravity environment
Percentage of overweight or obese population in 2010, Data source: OECD's iLibrary.
Colorful fruits and vegetables may be components of a healthy diet.
Jack Drummond’s single-paragraph article in 1920 which provided structure and nomenclature used today for vitamins
James Lind conducted in 1747 the first controlled clinical trial in modern times, and in 1753 published Treatise on Scurvy.
Followed for a millennium and a half, Galen (1st century) created the first coherent (although mistaken) theory of nutrition.
Swimmers perform squats prior to entering the pool in a U.S. military base, 2011.
Summary of long-term adaptations to regular aerobic and anaerobic exercise. Aerobic exercise can cause several central cardiovascular adaptations, including an increase in stroke volume (SV) and maximal aerobic capacity (VO2 max), as well as a decrease in resting heart rate (RHR). Long-term adaptations to resistance training, the most common form of anaerobic exercise, include muscular hypertrophy, an increase in the physiological cross-sectional area (PCSA) of muscle(s), and an increase in neural drive, both of which lead to increased muscular strength. Neural adaptations begin more quickly and plateau prior to the hypertrophic response.
Proteins are chains of amino acids found in most nutritional foods.
Roper's gymnasium, Philadelphia, circa 1831.
In the news
- See also: Biology (below)
Health – Health is a state of complete physical, mental and social well-being. this is a level of functional and (or) metabolic efficiency of a person in mind, body and spirit; being free from illness, injury or pain (as in “good health” or “healthy”). The World Health Organization (WHO) defined health in its broader sense in 1946 as "a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity."
- Death – cessation of life.
- Exercise – any bodily activity that enhances or maintains physical fitness and overall health and wellness. It is performed for various reasons including strengthening muscles and the cardiovascular system, honing athletic skills, weight loss or maintenance, and mental health including the prevention of depression. Frequent and regular physical exercise boosts the immune system, and helps prevent the "diseases of affluence" such as heart disease, cardiovascular disease, Type 2 diabetes mellitus and obesity.
- Nutrition – provision, to cells and organisms, of the materials necessary (in the form of food) to support life.
- Life extension – The study of slowing down or reversing the processes of aging to extend both the maximum and average lifespan.
- Health sciences – applied sciences that address the use of science, technology, engineering or mathematics in the delivery of healthcare to human beings.
- Medicine – science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness.
- Anesthesia – a way to control pain during a surgery or procedure by using medicine called anesthetics.
- Cardiology – branch of medicine dealing with disorders of the human heart. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology.
- Clinical research – aspect of biomedical research that addresses the assessment of new pharmaceutical and biological drugs, medical devices and vaccines in humans.
- Diabetes – a group of metabolic diseases in which the person has high blood glucose (blood sugar) above 200mg/dl, either because insulin production is inadequate, or because the body's cells do not respond properly to insulin, or both.
- Dentistry – branch of medicine that is involved in the study, diagnosis, prevention, and treatment of diseases, disorders and conditions of the mouth, maxillofacial area and the adjacent and associated structures (teeth) and their impact on the human body.
- Emergency medicine – medical specialty involving care for undifferentiated, unscheduled patients with acute illnesses or injuries that require immediate medical attention. Emergency physicians undertake acute investigations and interventions to resuscitate and stabilize patients.
- Obstetrics – medical specialty dealing with the care of all women's reproductive tracts and their children during pregnancy (prenatal period), childbirth and the postnatal period.
- Trauma and Orthopedics – medical specialty dealing with bones, joints and operative management of trauma.
- Psychiatry – medical specialty devoted to the study and treatment of mental disorders. These mental disorders include various affective, behavioural, cognitive and perceptual abnormalities.
- Autism a mental condition, present from early childhood, characterized by great difficulty in communicating and forming relationships with other people and in using language and abstract concepts.
- Bipolar disorder – mental disorder that causes periods of depression and periods of abnormally elevated mood.
- Psychiatric survivors movement – is a diverse association of individuals who either currently access mental health services (known as consumers or service users), or who are survivors of interventions by psychiatry, or who are ex-patients of mental health.