Late Adulthood

• Lifespan or Maximum Lifespan


  The greatest age reached by any member of a given population (or species)
• Life expectancy


  The average number of years that members of a population (or species) live
• According to the World Health Organization (WHO) (2019) global life expectancy for those born in 2019 is 72.0 years, with females reaching 74.2 years and males reaching 69.8 years
• Women live longer than men around the world, and the gap between the sexes has remained the same since 1990
• Age Categories in Late Adulthood

  • Young–old (65-74)
  • old-old (75-84)
  • the oldest-old (85-99)
  • centenarians (100+)
• These age categories


  • Are based on the conceptions of aging including, biological, psychological, social, and chronological differences
  • Reflect the increase in longevity of those living to this latter stage
• Young-old


  Generally, this age span includes many positive aspects and is considered the "golden years" of adulthood
• When compared to those who are older, the young-old experience relatively good health and social engagement, knowledge and expertise, and adaptive flexibility in daily living
• The young-old also show strong performance in attention, memory, and crystallized intelligence
• The young-old are more similar to those in midlife
• The young-old are less likely to require long-term care, to be dependent or poor, and more likely to be married, working for pleasure rather than income, and living independently
• Those in the young-old age period feel a sense of happiness and emotional well-being that is better than at any other period of adulthood
• Old-old


  Adults in this age period are likely to be living independently, but often experience physical impairments as chronic diseases increase after age 75
• Congestive heart failure is 10 times more common in people 75 and older than in younger adults
• Half of all cases of heart failure occur in people after age 75
• Hypertension and cancer rates are also more common after 75, but because they are linked to lifestyle choices, they typically can be prevented, lessened, or managed
• Oldest-old


  This age group often includes people who have more serious chronic ailments among the older adult population
• In the U.S., the oldest-old represented 14% of the older adult population in 2015
• The oldest-old are projected to be nearly 18 million by 2050, or about 4.5% of the U. S. population, compared with less than 2% of the population today
• Females comprise more than 60% of those 85 and older, but they also suffer from more chronic illnesses and disabilities than older males
• Centenarians


  A segment of the oldest-old who are 100 and older, and some are also referred to as supercentenarians, those 110 and older
• In 2015 there were nearly half a million centenarians worldwide, and it is estimated that this age group will grow to almost 3.7 million by 2050
• Learning Objectives: Physical Development in Late Adulthood
• Programmed Theories


  Theories that follow a biological timetable, possibly a continuation of childhood development
• Damage or Error Theories

  Theories that emphasize environmental factors that cause cumulative damage in organisms
• Genetics play a role in longevity, but scientists are still attempting to identify which genes are responsible
• Evolutionary Theory


  Emphasizes the importance of natural selection; that is, those genes that allow one to survive and reproduce will be more likely to be transmitted to offspring
• Cellular Clock Theory


  Suggests that biological aging is due to the fact that normal cells cannot divide indefinitely
• DNA Damage


  Over time DNA, which contains the genetic code for all organisms, accumulates damage
• Mitochondrial Damage


  Damage to mitochondrial DNA can lead to a decaying of the mitochondria, which is a cell organelle that uses oxygen to produce energy from food
• Free Radicals


  When the mitochondria use oxygen to produce energy, they also produce potentially harmful byproducts called oxygen free radicals
• After age 30 people tend to lose lean tissue, and some of the cells of the muscles, liver, kidney, and other organs are lost
• Tissue loss reduces the amount of water in the body and bones may lose some of their minerals and become less dense
• With age, skin becomes thinner, less elastic, loses fat, and no longer looks plump and smooth
• People typically lose almost one-half inch every 10 years after age 40, and height loss is even more rapid after age 70
• Men often gain weight until about age 55, and then begin to lose weight later in life, possibly related to a drop in the male sex hormone testosterone
• Women usually gain weight until age 65 and then begin to lose weight
• In late adulthood, all the senses show signs of decline, especially among the oldest-old
• Three serious eye diseases are more common in older adults: Cataracts, macular degeneration, and glaucoma
• Our sense of taste, or gustation, appears to age well