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
is the study and analysis of the distribution (who, when, and where) and determinants
of health and disease conditions in defined populations
It is the cornerstone of public health
, and shapes policy decisions and evidence-based practice
by identifying risk factors
for disease and targets for preventive healthcare
. Epidemiologists help with study design, collection, and statistical analysis
of data, amend interpretation and dissemination of results (including peer review
and occasional systematic review
). Epidemiology has helped develop methodology
used in clinical research
, public health
studies, and, to a lesser extent, basic research
in the biological sciences.
Major areas of epidemiological study include disease causation, transmission
investigation, disease surveillance
, environmental epidemiology
, forensic epidemiology
, occupational epidemiology
, and comparisons of treatment effects such as in clinical trials
. Epidemiologists rely on other scientific disciplines like biology
to better understand disease processes, statistics
to make efficient use of the data and draw appropriate conclusions, social sciences
to better understand proximate and distal causes, and engineering
for exposure assessment
. Read more...
is both the abstract
state of being clean and free from germs and dirt, and the habit of achieving and maintaining that state. Cleanliness is often achieved through cleaning
Cleanliness is a good quality, as indicated by the aphorism
: "cleanliness is next to godliness
", and may be regarded as contributing to other ideals such as 'health
' and 'beauty
In emphasizing an ongoing procedure or set of habits for the purpose of maintenance and prevention, the concept of cleanliness differs from purity
, which is a physical, moral, or ritual state of freedom from pollutants. Whereas purity is usually a quality of an individual or substance, cleanliness has a social dimension, or implies a system of interactions. "Cleanliness," observed Jacob Burckhardt
, "is indispensable to our modern notion of social perfection." A household or workplace may be said to exhibit cleanliness, but not ordinarily purity; cleanliness also would be a characteristic of the people who maintain cleanness or prevent dirtying.
On a practical level, cleanliness is thus related to hygiene
is one way of achieving physical cleanliness, usually with water
and often some kind of soap
procedures are of the utmost importance in many forms of manufacturing. Read more...
(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...
) is a branch of biology
dealing with the endocrine system
, its diseases, and its specific secretions known as hormones
. It is also concerned with the integration of developmental events proliferation, growth, and differentiation, and the psychological or behavioral activities of metabolism
, growth and development
, and sensory perception
caused by hormones
. Specializations include behavioral endocrinology and comparative endocrinology
The endocrine system consists of several glands
, all in different parts of the body, that secrete hormones directly into the blood rather than into a duct system. Hormones have many different functions and modes of action; one hormone may have several effects on different target organs, and, conversely, one target organ may be affected by more than one hormone. Read more...
is a health care profession that involves examining the eyes
and applicable visual systems
for defects or abnormalities as well as the medical diagnosis and management of eye disease. Traditionally, the field of optometry began with the primary focus of correcting refractive error through the use of spectacles. Modern day optometry, however, has evolved through time so that the educational curriculum additionally includes intensive medical training in the diagnosis and management of ocular disease in countries where the profession is established and regulated.Optometrists
(also known as doctors of optometry
in the United States and Canada for those holding the O.D. degree, or ophthalmic opticians
in the United Kingdom) are health care professionals who provide primary eyecare through comprehensive eye examinations
to detect and treat various visual abnormalities and eye diseases. Being a regulated profession, an optometrist's scope of practice may differ depending on the location. Thus, disorders or diseases detected outside the treatment scope of optometry are referred out to relevant medical professionals for proper care, more commonly to ophthalmologists
who are physicians that specialize in tertiary medical and surgical care of the eye. Optometrists typically work closely together with other eye care professionals
such as ophthalmologists and opticians
to deliver quality and efficient eyecare to the general public.
The term "optometry" comes from the Greek words ὄψις
; "view") and μέτρον
; "something used to measure", "measure", "rule"). The word entered the language when the instrument for measuring vision was called an optometer
, (before the terms phoropter
or refractor were used). The root word opto
is a shortened form derived from the Greek word ophthalmos
meaning, "eye." Like most healthcare professions, the education and certification of optometrists is regulated in most countries. Optometric professionals and optometry-related organizations interact with governmental agencies, other healthcare professionals, and the community to deliver eye- and vision-care. Read more...
Major depressive disorder
), also known simply as depression
, is a mental disorder
characterized by at least two weeks of low mood
that is present across most situations. It is often accompanied by low self-esteem
, loss of interest
in normally enjoyable activities, low energy, and pain
without a clear cause. People may also occasionally have false beliefs
or see or hear things that others cannot
. Some people have periods of depression
separated by years in which they are normal, while others nearly always have symptoms present. Major depressive disorder can negatively affect a person's personal life, work life, or education, as well as sleeping, eating habits, and general health. Between 2–8% of adults with major depression die by suicide
, and about 50% of people who die by suicide had depression or another mood disorder
The cause is believed to be a combination of genetic
, environmental, and psychological factors. Risk factors include a family history
of the condition, major life changes, certain medications, chronic health problems
, and substance abuse
. About 40% of the risk appears to be related to genetics. The diagnosis of major depressive disorder is based on the person's reported experiences and a mental status examination
. There is no laboratory test for major depression. Testing, however, may be done to rule out physical conditions that can cause similar symptoms. Major depression is more severe and lasts longer than sadness
, which is a normal part of life. The United States Preventive Services Task Force
(USPSTF) recommends screening for depression among those over the age 12, while a prior Cochrane review
found that the routine use of screening questionnaires has little effect on detection or treatment.
Typically, people are treated with counseling
and antidepressant medication
. Medication appears to be effective, but the effect may only be significant in the most severely depressed. It is unclear whether medications affect the risk of suicide. Types of counseling used include cognitive behavioral therapy
(CBT) and interpersonal therapy
. If other measures are not effective, electroconvulsive therapy
(ECT) may be considered. Hospitalization may be necessary in cases with a risk of harm to self and may occasionally occur against a person's wishes
. Read more...
A selection of plant-sourced food
consumed by humans. The human diet can vary widely.
is the sum of food consumed by a person or other organism
The word diet often implies the use of specific intake of nutrition
reasons (with the two often being related). Although humans are omnivores
, each culture and each person holds some food preferences or some food taboos. This may be due to personal tastes or ethical reasons. Individual dietary choices may be more or less healthy.
Complete nutrition requires ingestion and absorption of vitamins
, essential amino acids from protein and essential fatty acids from fat-containing food, also food energy
in the form of carbohydrate, protein, and fat. Dietary habits and choices play a significant role in the quality of life
. Read more...
Newspaper headlines from around the world about polio vaccine
tests (13 April 1955)
has been defined as "the science and art of preventing disease, prolonging life and promoting human health
through organized efforts and informed choices of society, organizations, public and private, communities and individuals". Analyzing the health of a population
and the threats it faces is the basis for public health. The public
can be as small as a handful of people or as large as a village or an entire city; in the case of a pandemic
it may encompass several continents. The concept of health
takes into account physical, psychological and social well-being. As such, according to the World Health Organization
, it is not merely the absence of disease or infirmity.
Public health is an interdisciplinary
field. For example, epidemiology
of health services
are all relevant. Other important subfields include environmental health
, community health
, behavioral health
, health economics
, public policy
, mental health
, occupational safety
, gender issues in health, and sexual and reproductive health
Public health aims to improve the quality of life through prevention and treatment of disease
, including mental health. This is done through the surveillance
of cases and health indicators
, and through the promotion of healthy behaviors. Common public health initiatives include promotion of handwashing
, delivery of vaccinations
, suicide prevention
, and distribution of condoms
to control the spread of sexually transmitted diseases
. 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
, behavior analysis
, occupational therapy
, clinical psychology
, physical therapy
, special education
, 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...
The structure of an alpha amino acid in its un-ionized form
are organic compounds
) and carboxyl
(-COOH) functional groups
, along with a side chain
(R group) specific to each amino acid. The key elements
of an amino acid are carbon
(O), and nitrogen
(N), although other elements are found in the side chains of certain amino acids. About 500 naturally occurring amino acids are known (though only 20 appear in the genetic code
) and can be classified in many ways. They can be classified according to the core structural functional groups' locations as alpha- (α-), beta- (β-), gamma- (γ-) or delta- (δ-)
amino acids; other categories relate to polarity
level, and side chain group type (aliphatic
, containing hydroxyl
, etc.). In the form of proteins
, amino acid residues
form the second-largest component (water
is the largest) of human muscles
and other tissues
. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter
transport and biosynthesis
, amino acids having both the amine and the carboxylic acid groups attached to the first (alpha-) carbon
atom have particular importance. They are known as 2-, alpha-,
or α-amino acids
NCHRCOOH in most cases, where R is an organic substituent
known as a "side chain
"); often the term "amino acid" is used to refer specifically to these. They include the 22 proteinogenic
("protein-building") amino acids, which combine into peptide
chains ("polypeptides") to form the building-blocks of a vast array of proteins
. These are all L
), although a few D
-amino acids ("right-handed") occur in bacterial envelopes
, as a neuromodulator
), and in some antibiotics
Twenty of the proteinogenic amino acids are encoded directly by triplet codons
in the genetic code
and are known as "standard" amino acids. The other two ("non-standard" or "non-canonical") are selenocysteine
(present in many prokaryotes
as well as most eukaryotes
, but not coded directly by DNA
), and pyrrolysine
(found only in some archea
and one bacterium
). Pyrrolysine and selenocysteine are encoded via variant codons; for example, selenocysteine is encoded by stop codon
and SECIS element
(which is often the initial amino acid of proteins in bacteria, mitochondria
, and chloroplasts
) is generally considered as a form of methionine
rather than as a separate proteinogenic amino acid. Codon–tRNA
combinations not found in nature can also be used to "expand" the genetic code
and form novel proteins known as alloproteins
incorporating non-proteinogenic amino acids
. 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...
Comparison of male and female life expectancy at birth for countries and territories as defined in the 2011 CIA Factbook
, with selected bubbles labelled. The green dotted line corresponds to equal female and male life expectancy. The apparent 3D volumes of the bubbles are linearly proportional to their population. (In the SVG file
, hover over a bubble to highlight it and show its data.)
The word "longevity
" is sometimes used as a synonym for "life expectancy
" in demography
. However, the term longevity
is sometimes meant to refer only to especially long-lived members of a population, whereas life expectancy
is always defined statistically as the average number of years remaining at a given age. For example, a population's life expectancy at birth is the same as the average age at death for all people born in the same year (in the case of cohorts
). Longevity is best thought of as a term for general audiences meaning 'typical length of life' and specific statistical definitions should be clarified when necessary.
Reflections on longevity have usually gone beyond acknowledging the brevity of human life and have included thinking about methods to extend life. Longevity has been a topic not only for the scientific community but also for writers of travel
, science fiction
, and utopian
There are many difficulties in authenticating the longest human life span
ever by modern verification standards, owing to inaccurate or incomplete birth statistics. Fiction, legend, and folklore have proposed or claimed life spans in the past or future vastly longer than those verified by modern standards, and longevity narratives
and unverified longevity claims
frequently speak of their existence in the present. Read more...
A woman doing static stretching
is a form of physical exercise
in which a specific muscle
(or muscle group) is deliberately flexed or stretched in order to improve the muscle's felt elasticity
and achieve comfortable muscle tone
. The result is a feeling of increased muscle control, flexibility, and range of motion. Stretching is also used therapeutically
to alleviate cramps
In its most basic form, stretching is a natural and instinctive
activity; it is performed by humans
and many other animals
. It can be accompanied by yawning
. Stretching often occurs instinctively after waking from sleep, after long periods of inactivity, or after exiting confined spaces and areas.
Increasing flexibility through stretching is one of the basic tenets of physical fitness. It is common for athletes to stretch before (for warming up
) and after exercise in an attempt to reduce risk of injury and increase performance. Read more...
Did you know...
- ... that in the American scholar Scott Rozelle's 30-year career as a development economist, he has been mostly concerned with children's health conditions in rural China?
- ... that despite being a prolific artist of 19th-century London, Robert Blemmell Schnebbelie died of starvation in Camden Town?
- ... that Irish hockey umpire Carol Metchette was forced to retire from umpiring for being too old, despite having the highest fitness test results of any international umpire?
- ... that following her diagnosis of terminal lung cancer, the British Vogue health editor Deborah Hutton campaigned to raise awareness of the dangers of smoking for teenage girls?
- ... that the 1257 eruption of Samalas was one of the largest eruptions of the Holocene, and may have triggered the Little Ice Age and famines in Europe?
- ... that sexual-health doctor Mags Portman and activist Greg Owen worked together to provide accessible HIV medication, preventing thousands of new HIV infections in the United Kingdom?
Do you have a question about Health that you can't find the answer to?
Consider asking it at the Wikipedia reference desk.
For editor resources and to collaborate with other editors on improving Wikipedia's Health-related articles, see WikiProject Health.
Percentage of obese population in 2010, Data source: OECD's iLibrary.
Running has become a popular form of exercise.
A lady washing her hands c. 1655
A woman jogging at a beach in the U.S. to maintain/improve her physical fitness
James Lind conducted in 1747 the first controlled clinical trial in modern times, and in 1753 published Treatise on Scurvy.
Postage stamp, New Zealand, 1933. Public health has been promoted – and depicted – in a wide variety of ways.
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.
Colorful fruits and vegetables may be components of a healthy diet.
Proteins are chains of amino acids found in most nutritional foods.
Percentage of overweight or obese population in 2010, Data source: OECD's iLibrary.
An astronaut, Daniel Tani, working out with a short bar to increase his upper body strength while in a microgravity environment
Hippocrates lived about 400 BC, and Galen and the understanding of nutrition followed him for centuries.
Followed for a millennium and a half, Galen (1st century) created the first coherent (although mistaken) theory of nutrition.
Jack Drummond’s single-paragraph article in 1920 which provided structure and nomenclature used today for vitamins
Swimmers perform squats prior to entering the pool in a U.S. military base, 2011.
Roper's gymnasium, Philadelphia, circa 1831.
Calcium combined with vitamin D (as calciferol) supplement tablets with fillers.
A bottle of B-complex vitamin pills
In the news
- 24 March 2019 – Stoneman Douglas High School massacre aftermath
- More than 60 school, county, city, child services and law enforcement officials, as well as mental health specialists, teachers and parents, hold an emergency meeting after the suicide of a second Stoneman Douglas survivor. Florida's emergency chief is requesting the state Legislature provide more mental health resources for the community. Coral Springs, Florida, police reported that, Saturday night, a current sophomore killed himself. Last week, Sydney Aiello, a 19-year-old graduate who had recently been diagnosed with post-traumatic stress disorder, took her own life. (The Guardian) (Miami Herald)
- 9 March 2019 –
- Tunisian health minister Abderraouf Cherif resigns following the deaths of 11 newborn babies since Thursday at a hospital in the capital Tunis. Evidence suggests all 11 died from septic shock. Tunisia's public healthcare had been considered one of the best in North Africa, but it has operated less smoothly since the 2011 revolution. (BBC)
- 8 March 2019 – Politics of Finland
- The entire coalition government of Finland resigns after a failure to deliver on healthcare reform, a month ahead of the country's general election. The coalition, made up of Prime Minister Juha Sipilä's Centre Party, the conservative National Coalition Party and the Eurosceptic Blue Reform Party, were unable to agree on a package that would have slowed healthcare spending over the next decade. The government will be interim until April elections. (Reuters)
- 17 February 2019 –
- Israeli Prime Minister Benjamin Netanyahu appoints intelligence minister Israel Katz to take over the foreign minister portfolio. Netanyahu retains his defence minister and health minister roles. Israel's parliamentary elections are scheduled for 9 April 2019. (Reuters) (The Jewish Chronicle)
- 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.