Middle age is the period of life beyond young adulthood but before the onset of old age. The general term Young adult refers to different age groups based on context: In popular usage, young adult is a euphemism for an adolescent. ... An old man. ...

Various attempts have been made to define this age, which is around the third quarter of the average life span of human beings. According to Collins Dictionary, this is "... usually considered to occur approximately between the ages of 40 and 60", The OED gives a similar definition but with a later start point "... the period between youth and old age, about 45 to 60." The US Census lists middle age as including both the age categories 35 to 44 and 45 to 54. Erik Erikson sees it ending a little later and defines middle adulthood as between 40 and 65. Life expectancy is the average number of years remaining for a living being (or the average for a class of living beings) of a given age to live. ... Human beings are defined variously in biological, spiritual, and cultural terms, or in combinations thereof. ... Collins was a Scottish printing company founded by a schoolmaster, William Collins, in Glasgow in 1819. ... OED stands for Oxford English Dictionary Office of Enrollment & Discipline This page concerning a three-letter acronym or abbreviation is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... This article needs additional references or sources for verification. ...

In many Western societies this is seen to be the period of life in which a person is expected to have settled down in terms of their sense of identity and place in the world, be raising a family, and have established career stabilty. It is also a period often associated with the potential onset of mid-life crisis. // Computer programming In object-oriented programming, object identity is a mechanism for distinguishing different objects from each other. ... A family in Ouagadougou, Burkina Faso in 1997 A family consists of a domestic group of people (or a number of domestic groups), typically affiliated by birth or marriage, or by analogous or comparable relationships — including domestic partnership, cohabitation, adoption, surname and (in some cases) ownership (as occurred in the... This article does not cite any references or sources. ... A mid-life crisis is an emotional state of doubt and anxiety in which a person becomes uncomfortable with the realization that life is halfway over. ...

Health

Middle-aged adults often show visible signs of ageing such as loss of skin elasticity and graying of the hair. Physical fitness usually wanes, with a 5-10 kg (10-20 lb) accumulation of body fat, reduction in aerobic performance and a decrease in maximal heart rate. Strength and flexibility also decrease throughout middle age. However, people age at different rates and there can be large differences between individuals of the same age. ^[1] The effects of ageing on a human face Elderly woman Ageing or aging is the process of systems deterioration with time. ... Beyond overall skin structure, refer below to: See-also. ... Hair color is the result of pigmentation due to the presence of the chemicals of melanin and phaeomelanin. ... This article does not cite any references or sources. ... Look up strength in Wiktionary, the free dictionary. ... ‹ The template below (Expand) is being considered for deletion. ...

Female fertility declines significantly after age 40, and an advanced maternal age increases the risk of a child being born with some disorders such as Down’s Syndrome. Some conditions are also correlated with advanced paternal age. Most women go through the menopause, which ends natural fertility, in their late 40s or 50s. ^[2] Fertility is a measure of reproduction: the number of children born per couple, person or population. ... Graph showing increased risk of Down syndrome over time The maternal age effect describes the exponentially increasing risks for numerical chromosomal abnormalities among her gametes as a prospective mother ages. ... Down syndrome or trisomy 21 (Downs Syndrome in British English[1]) is a genetic disorder caused by the presence of all or part of an extra 21st chromosome. ... Paternal age effect Scientists know that a woman’s age at the time she conceives can affect her offspring’s genetic make-up. ... Menopause is the physiological cessation of menstrual cycles associated with advancing age in women. ...

In developed countries, yearly mortality begins to increase from age 40 onwards, mainly due to age-related health problems such as heart disease and cancer. ^{[3] [4]} However, the majority of middle-aged people in industrialized nations can expect to live into old age. Life expectancy in developing countries is much lower and the risk of death at all ages is higher. ^[3] A developed country is a country that has achieved (currently or historically) a high degree of industrialization, and which enjoys the higher standards of living which wealth and technology make possible. ... Heart disease is an umbrella term for a number of different diseases which affect the heart and is the leading cause of death in the United States as of 2007. ... Cancer is a class of diseases or disorders characterized by uncontrolled division of cells and the ability of these to spread, either by direct growth into adjacent tissue through invasion, or by implantation into distant sites by metastasis (where cancer cells are transported through the bloodstream or lymphatic system). ... An old man. ... World map of human life expectancy, 2005 Life expectancy is a statistical measure of the average length of survival of a living thing. ... A developing country is a country with low average income compared to the world average. ...

Positive ageing

Some people ^[5] challenge the concept that middle age is something to dread. They assert that with the right attitude and careful planning, middle age can be truly a person's best years. Those age-positive groups range from advocacy groups such as the American Association of Retired Persons (AARP) to purely social clubs like the Red Hat Society. AARP (formerly, but no longer, known as the American Association of Retired Persons) is a United States-based non-government organization dedicated to the interests of persons aged 50 and over. ... The Red Hat Society is a social organization for women over 50. ...

Further listening

• Does Age Quash Our Spirit of Adventure?, a segment on NPR's "All Things Considered" on an aging study done by middle-age neuroscientist Robert Sapolsky
• Ali Khan, Living Fully at Forty and Beyond

NPR logo For other meanings of NPR see NPR (disambiguation) National Public Radio (NPR) is a private, not-for-profit corporation that sells programming to member radio stations; together they are a loosely organized public radio network in the United States. ... All Things Considered (ATC), is a news radio program in the United States, broadcast on the National Public Radio network. ... Robert Maurice Sapolsky (b. ...

See also

• Youth
• Young adult
• Old age
• Aging
• Mid-Life Crisis

For other uses, see Youth (disambiguation) Youth is defined by Websters New World Dictionary as, The time of life when one is young; especially: a: the period between childhood and maturity b: the early period of existence, growth, or development. ... The general term Young adult refers to different age groups based on context: In popular usage, young adult is a euphemism for an adolescent. ... An old man. ... Ageing or aging is the process of getting older. ... A mid-life crisis is an emotional state of doubt and anxiety in which a person becomes uncomfortable with the realization that life is halfway over. ...

References

• Collins Concise Dictionary 4th edition 1999 Collins (an imprint of Harper Collins Publishers) Glasgow ISBN 0004722574
• http://www.askoxford.com/concise_oed/middleage?view=uk
• LifeTwo

1. ^ Shephard, Roy J. (7 March 1998). "Aging and Exercise". Encyclopedia of Sports Medicine and Science. Retrieved on 2007-06-26. 
2. ^ BBC medical notes
3. ^ ^{a b} Life Expectancy Profiles. BBC (6th June 2005). Retrieved on 2007-06-26.
4. ^ UK cancer mortality statistics by age. Cancer Research UK (May 2007). Retrieved on 2007-06-26.
5. ^ Saga