2 - Long version:
The views expressed by the presenter are for the purposes of debate and do not
necessarily represent his own opinions, nor are they intended to represent in
any way the opinions or other views of the AGHE. Prepared
and presented by Augustine G. DiGiovanna.
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The question being debated is: Will advocacy for and application of effective and innovative practices and procedures that increase both mean life expectancy and maximum life span result in augmented quality of human life for most of the world's population, or in the universal erosion of the quality of all life on earth?
I speak in support of the latter outcome. I base my opposition on several lines of evidence which include the following; (1) current and projected demographics, especially those pertaining to elders; (2) the ambiguity and lack of consensus regarding what is meant by "quality of life"; (3) and the adverse effects of large and growing populations on multiple aspects of quality of life.
First, we must recognize facts about present populations and our best projections about future populations. These projections are based on certain assumptions, one of which is having a change in mean longevity but having no change in maximum longevity. When demographers consider the variables and possible scenarios that affect life expectancy, they conclude with ninety-five percent confidence that future life expectancies will fall within a certain range. The first graph shows this range from birth for US women and men. Note the most likely or "middle series" life expectancies, and the highest projected life expectancies. The most likely life expectancy for those born in the year 2050 is only 84.3 for women and only 79.7 for men. The second graph shows this range for those who will be age 65 in the year 2050. The most likely life expectancies for those elders is only 87.4 for women and only 85.3 for men. Anyone considering increasing life expectancies expects to increase them far above the middle series, and probably far above even the highest projections shown.
If we succeed in doing this, the demographers' projections about population size are dangerously low. Moreover, their projections about elders in the population are especially low. This is because in the US and other developed countries, survival rates during childhood and young adulthood are already so high that only increasing survival among older adults can have a significant effect on life expectancy. You can see this in the survival course in graph three.
But let's see demographers' population size and age distributions based on only their "middle series" life expectancies. Graph four shows that by the year 2050 the US population will increase from its present 280 million to 404 million and will still be rising. Graph five-a and graph five-b (Click here and go to page vi) show that by the year 2050 the world population will increase from 6.2 billion to 9.1 billion and will still be rising. Graph six shows that most of the global population increase will occur in the developing nations. Most of this increase will occur among adults, especially among elders. The result will be an extremely high human population made up of a new and disproportionately high percentage of elders, as shown in graph seven and United Nations maps. Any increase in life expectancies beyond these assumptions would only make a bad situation worse.
2. Quality of life
Now let's look at the meaning of quality of life. One main point here is that there is no agreement on what "quality of life" means. Of course, this makes it impossible for anyone to claim that there will be an improvement in quality of life. But let's at least examine some criteria for quality of life. The **US government says that quality of life includes a "general sense of happiness and satisfaction with our lives and environment that encompasses all aspects of life, including health, recreation, culture, rights, values, beliefs, aspirations, and conditions that support life containing these elements." Other descriptions of quality of life include one's food, physical independence, economic status, social status, social situation, self-efficacy, self-determination, space, political circumstances, employment, and exposure to wilderness. I hope you noticed that some of these criteria are overly vague. Still, the point I will make is that increases in population size with increases in the percentage of elders will cause a decline in many, if not all, of these criteria. I have time to address only a few of these.
First, consider health. Many diseases increase in frequency and severity with increasing age. Even with the current rate of increasing life expectancy and of medical advances, the number of afflicted elderly individuals is rising at an ever-increasing rate, as is the percentage of the population afflicted. Specific examples include eye disorders such as cataracts, age-related macular degeneration, glaucoma, diabetic retinopathy, and blindness; hearing impairment; dental disease, arthritis (the leading chronic and disabling condition among elders), cancer, depression; and dementias, of which Alzheimer's disease is by far the most common. The incidence of dementia among elders doubles every five years starting at age 60. Dementia occurs in eleven percent of those 80-84, twenty-one percent for those 85-89, and thirty-nine percent for those 90-94. At that rate, increasing life expectancy to age 100 means that more than three quarters of the population will become demented and remain so for at least several years. Meanwhile, our resources for preventing, for treating, and for making accommodations for these diseases are already being outstripped. We already lack the human, fiscal, and physical resources even to sustain the status quo. This is true on an individual basis and even more so for diseases that fall within the realm of public health, such as disease-carrying vectors and epidemics like AIDS. Sadly, for the past 50 years, AIDS is one of the two main factors holding the world's population explosion in check. (The other factor is declining fertility rates.) Increasing mean longevity would also mean general and widespread declines in health status for elders and, therefore, a widespread decline in quality of life for elders and for society as a whole. It would also likely mean new epidemics of transmissible diseases, such as ebola, and diseases that are now considered rare. Just this last scenario is what has already occurred with AIDS and Alzheimer's disease.
Next, consider food. Ample quality food is necessary not only for survival but also for a high quality of life. Our food supply comes from agriculture and harvests from the sea. In many areas, arable land is being lost due to human activities including urbanization and development, erosion, salinization, and pollution. Problems like this are now part of living on the Eastern Shore of Maryland, which is chicken and hog country. Currently, providing adequate food supply globally is already impossible due to inappropriate public policies such as tariffs and trade agreements, ineffective food distribution methods, and in an increasing number of cases, by recurring energy shortages. These factors plus overharvesting, such as oysters, crabs and fish species, are devastating our seafood supplies. The Chesapeake Bay is a good example.
In developing countries, problems providing ample quality food are getting worse faster than in developed countries due to more rapid urbanization and people choosing diets more like those in developed countries. As a specific example, increasing the amount of meat in the diet doubles the energy needed for each calorie of food and increases run-off and animal manure.
Of course, increasing populations make all these problems worse. Moreover, the faster a population increases, the more rapid, more numerous, and more severe are difficulties and undesirable outcomes from trying to provide adequate quality food. Simply stated, we are not feeding our global population now. Increasing life expectancy means even sooner widespread famine with not only biological but also political upheavals.
c. Dependency ratios
As people age, they become more dependent on others in a multitude of ways. Examples include assistance with daily living, health care, food supply, and economics. The number of young adults needed to care for a given number of elders is called the dependency ratio.
Both nationally and globally, dependency ratios are now increasing and already becoming problematic. Since the young adults of the next fifty years are already born, we know how many there will be to support the future elder generation. Both the national demographics and the global demographics show that with current life expectancies, dependency ratios will continue to increase dramatically. In just 25 years, the global dependency ratio will be 50 percent higher than it is now because of the increasing numbers and percentages of elders. One might suggest that a way to reduce this dependency ratio is to increase in birth rates. However, as nations develop, there is a spontaneous reduction in birth rates. Even if there were an increase in birth rates, that would only add to the world's overpopulation problems.
With time running out, I will only mention increases in economic difficulties that accompany increases in populations, especially those with increasing numbers and proportions of elders. Who has not already heard much about these? Prescription drug and all other health care; HMOs and the services they provide; Social Security; competition for jobs; and poverty among elders, especially those with fixed or declining incomes. Lurking in the background is also the fact that those who benefit from promoting technical ways of increasing longevity will promote spending to bring about such increases, exacerbating all the problems from an already growing population with rising numbers and percentages of elders.
From an ecological perspective, it is impossible to have a sustainable growing population. Resources such as the basics of food, water, and shelter are limited, and a growing population will eventually outstrip them. Then either the population stops growing and sustains its miserable lifestyle or it shrinks, often with a crash. And nature does not choose high quality of life methods for reducing populations. The human population is not immune to nature's laws. We are already experiencing these facts in growing pollution, urban blight, wilderness destruction, and most frightening of all, the beginning of the Earth's sixth major extinction. Each year approximately 27,000 species become extinct with few if any new ones appearing. And extinction is forever!
I will conclude with a paraphrase on the effects of increasing human longevity vis-a-vis quality of life, and especially for a population with many elders. "Any technical improvement can only relieve misery for a while. As long as misery is the only check on the size of a population, the technical improvement will enable the population to grow, and will soon enable more people than before to live in misery. The final result of technical improvements, therefore, is to increase the size of the population, which is to increase the total sum of human misery." (From: http://fizziker.com/AlBartlett/population.htm, Reflections On Sustainability, Population Growth And The Environment by Albert A. Bartlett.)
**(From : http://www.health.gov/healthypeople/Document/html/uih/uih_bw/uih_2.htm, Healthy People: 2010, page 10, Office of Disease Prevention and Health Promotion, U.S. Department of Health and Human Services)
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For more information - go to the following US Census Bureau site for more information about US population conditions and predictions.
US Census Bureau
Go to the following United Nations sites for more information about world population conditions and predictions.
The State of the World Population: 2001 - http://www.unfpa.org/swp/2001/english/index.html
World Population Prospects: The 2000 Revision - http://www.un.org/esa/population/publications/wpp2000/wpp2000h.pdf
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Prepared and presented by Augustine G. DiGiovanna
Copyright 2002: A.G. DiGiovanna, Professor of Biology, Salisbury University, agdigiovanna@Salisbury.edu