What aarp has to say about the current state of the aging problem

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"Cocoon" and "Fountain of Youth"

This is to remind you that the search for endless youth has been on peoples minds for some time

Lucas Cranach (1472 - 1553)

Longlived Creatures

Old sequoia 3500 yrs. old and still reproducing. Old fish 50 years old. . Old radiated tortoise 188 yrs old

Age vs Risk of Dying

A disparity exists between the life expectancy of the most deprived and the least deprived US citizens.

















Here is way to look at risk of dying vs age

Aging handout week 1

Aging is any change in an organism over time. Aging refers to a multidimensional process of physical, psychological, and social change (Hultsch and Deutsch). Some dimensions of aging grow and expand over time, while others decline. Reaction time, for example, may slow with age, while knowledge of world events and wisdom may expand (Schaie). Research shows that even late in life potential exists for physical, mental, and social growth and development. Aging is an important part of all human societies reflecting the biological changes that occur, but also reflecting cultural and societal conventions. Age is usually measured in full years — and months for young children. A person's birthday is often an important event.

The term "aging" is somewhat ambiguous. Stuart-Hamilton (1994) notes how distinctions may be made between "universal aging" (age changes that all people share) and "probabilistic aging" (age changes that may happen to some, but not all people as they grow older, such as the onset of Type Two diabetes). Chronological aging, referring to how old a person is, is arguably the most straightforward definition of aging and may be distinguished from "social aging" (society's expectations of how people should act as they grow older) and "biological aging" (an organism's physical state as it ages). Stuart-Hamilton also notes distinction between "proximal aging" (age-based effects that come about because of factors in the recent past) and "distal aging" (age-based differences that can be traced back to a cause early in person's life, such as childhood poliomyelitis).

Population aging is the increase in the number and proportion of older people in society. Population aging has three possible causes: migration, longer life expectancy (decreased death rate), and decreased birth rate. The societal effects of age are great. Young people tend to commit most crimes, they are more likely to push for political and social change, to develop and adopt new technologies, and to need education. Older people have different requirements from society and government as opposed to young people, and frequently differing values as well. Older people are also far more likely to vote, and in many countries the young are forbidden from voting, and thus the aged have comparatively more political influence.

[edit] Senescence

Main article: Senescence

In biology, senescence is the state or process of aging. Cellular senescence is a phenomenon where isolated cells demonstrate a limited ability to divide in culture (the "Hayflick Limit," discovered by Leonard Hayflick in 1965), while Organismal senescence is the aging of organisms.
A map showing median age figures for 2001
A map showing median age figures for 2001

Aging is not an unavoidable property of life. Instead, it is the result of a genetic program coded in genes. Numerous species show no sign of aging, the best known being perennial plants (e.g. trees) which can live thousands of years and be multiplied by cuttings without limit. Many amphibians and large fish also seem to be free of aging. In these species, adults constantly reproduce only to destroy their youngs, usually by eating them. Therefore, "immortal" species evolve more slowly than species that age.

Aging is believed to be favoured by natural selection because it accelerates the evolution rate of a species by increasing the number of generations per unit of time. By dying away, the old individuals liberate the resources for their offsprings, thus increasing their chance at survival. Essentially, aging is therefore the result of investing resources in reproduction, rather than maintenance of the body (the "Disposable Soma" theory).

Organismal aging is generally characterized by the declining ability to respond to stress, increasing homeostatic imbalance and increased risk of disease. Because of this, death is the ultimate consequence of aging.

Some researchers are treating aging as a "disease" in gerontology (specifically biogerontologists). That is, as genes that have an effect on aging are discovered, aging is increasingly being regarded in a similar fashion to other genetic conditions; potentially "treatable." As an example of genes known to affect the aging process, the sirtuin family of genes have been shown to have a significant effect on the lifespan of yeast and nematodes. Numerous other examples exist of genes that affect lifespan including RAS1 and RAS2 (yeast genes, although a human homologue exists). Over-expression of RAS2 increases lifespan in yeast substantially.

In addition to genetic ties to lifespan, diet has been shown to substantially affect lifespan in many animals. Specifically, caloric restriction (that is, restricting calories to 30-50% less than an ad libitum animal would consume, while still maintaining proper nutrient intake), has been shown to increase lifespan in mice up to 50%. Caloric restriction works on many other species beyond mice (including species as diverse as yeast and Drosophila), and appears (though the data is not conclusive) to increase lifespan in primates according to a study done on Rhesus monkeys at the National Institute of Health (US).


Drug companies are currently searching for ways to mimic the lifespan-extending effects of caloric restriction without having to severely reduce food consumption, and with respect to cellular senescence, it has been shown that individual cells can be immortalized by the introduction of an additional gene for telomerase.

[edit] Dividing the lifespan

A human life is often divided into various ages. Because biological changes are slow moving and vary from person to person, arbitrary dates are usually set to mark periods of human life. In some cultures the divisions given below are quite varied.

In the USA, adulthood legally begins at the age of eighteen or nineteen, while old age is considered to begin at the age of legal retirement (approximately 65).

* Pre-conception: Ovum, Spermatozoon, Pre-existence
* Conception: Fertilization
* Pre-birth: Conception to birth
* Infancy: Birth to 2
* Childhood: 2 to 12
* Adolescence: 13 to 20
* Early Adulthood: 21 to 34
* Middle Adulthood: 35 to 54
* Late Adulthood: 55+
* Death
* Post-Death: Decomposition, Cryonics, (Afterlife, Ghost)

Ages can also be divided by decade:

* Denarian: someone between 10 and 19 years of age
* Vicenarian: someone between 20 and 29 years of age
* Tricenarian: someone between 30 and 39 years of age
* Quadragenarian: someone between 40 and 49 years of age
* Quinquagenarian: someone between 50 and 59 years of age
* Sexagenarian: someone between 60 and 69 years of age
* Septuagenarian: someone between 70 and 79 years of age
* Octogenarian: someone between 80 and 89 years of age
* Nonagenarian: someone between 90 and 99 years of age
* Centenarian: someone between 100 and 109 years of age
* Supercentenarian: someone over 110 years of age

[edit] Cognitive effects

Steady decline in many cognitive processes are seen across the lifespan, starting in one's thirties. Research has focused in particular on memory and aging, and has found decline in many types of memory with aging, but not in semantic memory or general knowledge such as vocabulary definitions, which typically increases or remains steady. Changes in cognition with age are discussed by Stuart-Hamilton (1994). As Stuart-Hamilton notes, early studies generally found declines in intelligence in the elderly, but may be criticised for being cross-sectional studies rather than longitudinal studies. Interestingly, evidence suggests that verbal intelligence may show a less sharp decline than other forms of intelligence. Creativity may also show a decline in age. While it is popularly believed that as people age, after around the age of thirty, intellectual skill will show a gradual decline, a rather different theory discussed by Stuart-Hamilton (1994) is the "terminal drop theory", which suggests that intellectual skills remain steady throughout life, and then plummet sharply as people near the end of their lives. Individual variations in rate of cognitive decline may, according to this theory, be explained in terms of people have different lengths of life.

[edit] Terminology

The concept of successful aging can be traced back to the 1950s, and popularised in the 1980s. Previous research into aging exaggerated the extent to which health disabilities, such as diabetes or osteoporosis, could be attributed exclusively to age, and research in gerontology exaggerated the homogeneity of samples of elderly people.[4][5]

Successful aging consists of three components:[6]

1. Low probability of disease or disability;
2. High cognitive and physical function capacity;
3. Active engagement with life.

A greater number of people self-report successful aging than those that strictly meet these criteria.[4]

Successful aging is viewed by Fentleman, Smith and Peterson(1990) as an interdisciplinary concept, spanning both psychology and sociology. They state that in the behavioural sciences, successful aging is to be understood as "a quality of the transaction between the changing person and the changing society over the entire life span, but especially during a person's later years" (Fentleman et alia, 1990; p50).

Healthy aging has been proposed as a more appropriate term.[4]

Optimal aging better takes into account how many elderly people suffer some health detriments, the cultural diversity in approaches to death and how, in Western Europe and Northern America, people may approach death may differ from approaches taken in other cultures.[7]

Vaillant (2002; cited in Aldwin & Gilmer, 2004) has listed six dimensions of optimal aging:

1. No physical disability over the age of 75 as rated by a physician; 2. Good subjective health assessment (i.e. good self-ratings of one's health); 3. Length of undisabled life; 4. Good mental health; 5. Objective social support; 6. Self-rated life satisfaction in eight domains, namely marriage, income-related work, children, friendship and social contacts, hobbies, community service activities, religion and recreation/ sports.

[edit] Theories

[[edit] Biological theories

Reproductive-Cell Cycle Theory
The idea that aging is regulated by reproductive hormones that act in an antagonistic pleiotrophic manner via cell cycle signaling, promoting growth and development early in life in order to achieve reproduction, but later in life, in a futile attempt to maintain reproduction, become dysregulated and drive senescence (dyosis).
Wear-and-Tear theory
The idea that changes associated with aging are the result of chance damage that accumulates over time.
Somatic Mutation Theory
This is the biological theory that aging results from damage to the genetic integrity of the body’s cells.
Error Accumulation Theory
This is the idea that aging results from chance events that gradually damage the genetic code.
Accumulative-Waste Theory
The biological theory of aging that points to a buildup of cells of waste products that presumably interferes with metabolism.
Autoimmune Theory
This is the idea that aging results from gradual decline in the body’s immune system.
Aging-Clock Theory
The idea that aging results from a preprogrammed sequence, as in a clock, built into the operation of the nervous or endocrine system of the body.
Cross-Linkage Theory
This is the idea that aging results from accumulation of cross-linked compounds that interfere with normal cell function.
Free-Radical Theory
The idea that free radicals (unstable and highly reactive organic molecules, also named reactive oxygen species or oxidative stress) create damage that gives rise to symptoms we recognize as aging.
Mitohormesis
Recent evidence from Michael Ristow's laboratory suggests that a process called mitohormesis may prevent aging processes primarily caused by free radicals by increasing endogenous organismal resistance against reactive oxygen species and oxidative stress. [8]
Cellular Theory
This is the view that aging can be explained largely by changes in structure and function taking place in the cells of an organism.

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