Life Expectancy, Aging and Centenarian research

1
Life Expectancy, Aging and Centenarian research

• Carolyn R. Fallahi, Ph. D.

2
Life Expectancy

• The definition of Life span the maximum of
  years an individual can live.
• What is the maximum? Probably 120 years.

3
Average Life Expectancy

• Males 74
• women 80
• overall 77
• social factors affect when we will die.
• Sex differences longevity.

4
Predictors of Psychological longevity?

• 1921 Louis Terman
• Termite study
• Reanalyzed by Friedman et al (1995)

5
Centenarians

• The number of centenarians has increased.
• In 1980 there were only 15,000 centenarians.
• 2000 there were 77,000
• Projected that by 2050, 834,000
• New England Centenarian study.

6
Segerberg, 1982

• 1,200 centenarians interviewed
• What makes a difference?

7
Duke Longitudinal Study

• Palmore (1982)
• 25 year period
• 270 volunteers
• Ages 60-94

8
The Nun Study

• David Snowdon
• 678 nuns in Minnesota
• Issues intellectual job folic acid

9
Theories of Aging

• The first 3 theories that Im going to talk about
  today explain aging at a cellular level.

10
Theories of Aging

• Cellular Clock Theory Leonard Hayflick (1977)
  theory.
• Cells can divide a maximum number of times,
  approximately 75-80 times.
• As we age, our cells become less capable of
  dividing.

11
Cellular Clock Theory

• The tips of chromosomes are called telomeres and
  they are DNA sequences that cap chromosomes.
• After about 70 or 80 replications, the telomeres
  are dramatically reduced and the cell can no
  longer reproduce.

12
Free Radical Theory

• A second microbiological theory of aging is
  called the free-radical theory.
• People age b/c their cells metabolize energy.
• When they do this, they generate waste that
  includes unstable oxygen molecules known as free
  radicals.
• These cells cause damage.

13
Mitochonrial Theory

• The role of mitochondria tiny cellular bodies
  that supply energy for function, growth, and
  repair might play in aging.
• It seems that the decay of mitochondria is
  primarily due to oxidative damage and loss of
  critical micronutrients supplied by the cell.

14
Hormonal Stress Theory

• This theory explains aging not at a cellular
  level, but at a hormonal level.
• The hormonal stress theory argues that aging in
  the bodys hormonal system can lower resistance
  to stress and increase the likelihood of disease.

15
Which one is correct?

• This is anyones best guest.
• Maybe all of them are involved.