Life Expectancy Essay, Research Paper
7th Hour English
November 5, 2000
Research and biology will be the most important factors that determine how long people will be expected to live. With all the research and technology starting to prevail people in the future will live longer and healthier lives. There are many centenari-ans in the world now, that number will continue to rise rapidly in the next 20 years. The longest-lived human on record was 122 years 5 months and 14 days (Fischer 58). This number will easily be surpassed in the future. The average life expectancy in the United States has grown so much in the last 100 years it shows only a promising future. The overall goal is to live a long and healthy life, not just to extend the span. The average life expectancy in the United States has grown from 47 in 1900 to 76 in 1999. In the next century, biology should help more and more people reach the age of 100 (Weiner 74). Currently there are about 61,000 people over the age of 100, by the year 2020, it is predicted that there will be over 214,000 (56). The male sex does not seem to be living as long nor as healthy, 79 percent of the people over 100 are women (58). Although centenarians are rare, they are the fastest growing seg-ment of the United Population. The baby boomers will be one of the first generations to experience the great increase in the life expectancy rate. The Census Bureau projects that one in nine baby boomers will survive into their late 90?s, and one in 26 will reach 100. ?In 1900, the odds of living that long were one in 500,? stated Lynn Adler, founder of National Centenarian Awareness Projections (Cowley 59). Extending the average life expectancy age would be great, but living a healthy life while doing that would be even better. Americans are living longer and healthier. The disability rate among people older than 65 is steadily decreasing. Less and less of them are suffering from hypertension, arteriosclerosis, and dementia (59). In a study done in New England, 79 centenarians all lived independently through their early 90?s, and take an average of just one medica-tion (Cowley 59). One man, Miller Quarles, believes, ?Old age is a disease. It can be cured.? Dr. Walter M. Bortz of Stanford University thinks people should stay alive to 100 years of age. He believes the human body is built to last to the age of 120 years old (Hittner 126). A doctor with an opposing view believes that the length of our life is greatly determined by our hereditary genes, and that not everyone has what it takes to live to be 100 (Hittner 128). Miller Quarles is hoping that research labs and institutions will find a way to lengthen his life and keep him healthy. Some of the scientists might have found something to build on to. In the pasts century, medicines and better sanitation has helped the average life expectancy increase. People are starting to learn more about genes and chemical involvement in the aging process. The goal is not just to live longer, but to also live healthy. With the findings of a biological ?clock? ticking away in each of our cells, the knowing of how to reset those clocks would mean that people would never die from old age (Fischer 58). Seymour Benzer of the California Institute of Technology has made the first detailed map of a gene?s interior. He and his students discovered a ?clock gene?, which helps our bodies place itself in time (Weiner 75). Each time a cell divide, the strand gets a bit shorter. When it runs out, the cell can not divide anymore so it ages and dies. Scientists found that the enzyme telomerase can rebuild the strand over and over again. This substance has human cells living immortally in a petri dish at Geron Corp. for more than 200 regular lifetimes. None of the scientists have yet fig-ured out how to apply this to the entire body, but they are com-ing closer to being able to create new human parts that might not ever wear out (59). At Advance Cell Technology in Worcester, Mass., scientists have found that by merging a body cell, like a lung cell, with a cow egg cell stripped of its cow DNA, they are able to ?reprogram? the cell so it can rebuild its telomere strand and grow into a new organ. Scientists created a new blad-der and successfully transplanted it into a dog. Some scientists are predicting that today?s 40 year olds will be able to trade in their old organs for new and improved ones by the time they are 70 (Fischer 59). The research into telomere will be growing rap-idly and looks to be hopeful.
The way people live their life may be a contributing factor also. Many researchers believe that chronic illness is not be-cause of aging, but instead due to the lifestyles people choose (Cowley 58). Some believe environmental and behavioral factors affect as much as 70 percent of how long we live and how well we live it. Smoking increases the rate at which we age, exercising slows that rate down. Vitamins, eating nutritious diets, sun-screen, all factor in into living a healthier life. As part of the environment, it changes us. Our biology is effected by the food we eat to the stress we endure. Stress can age a person as much as any other single factor (Roizen, Stephenson 134+). We are somewhat in control of how long we live. There really are not too many surgeries that people can have to stay alive longer. Drugs and surgeries can only help the body out so much once it starts to deteriorate. The possibility of lengthening our lives while shortening our deaths is with in reach. ?Over the next 50 years, we?ll be completely reshaped by biology,? says Gregory Stock director of a program on medicine, technology, and society at the University of California-Los Ange-les Medical School. ?We?ll double human life span, but that will be a small part of all that will happen? (Fischer 58). Many studies are starting to show some hope that a cure is near. One man did a study on mice. In this study he deprived mice of food, they ate less, and lived longer. He found if mice eat only 60 percent of their preferred diet, they will live as long as 56 months-that is equal to 165 human years. The mice are smaller, but they retain their youthfulness and intellects as they age (Taubes 59). Another study, done on estrogen, found some hope that women will live longer than what they are. The drop of es-trogen in a woman can make their skin dry, her vaginal walls thin, and have an effect on their mood swings. Less estrogen in the body also makes bones lose density (hip fractures kill 65,000 American women each year), cholesterol levels worsen and blood vessels stiffen (Sharon-Begley 60). Research will continue to grow in all of these possibilities. The possibilities that many scientists are working on are: replacement organs- a few cells could give what the DNA is needs to build new organs that might never wear out; new neurons- the brain can not be replaced, but the ailing ones could be taken over by new ones that are injected into the brain; calorie reduc-tion- calorie intake is reduced to 60 or 70 percent the preferred diet; immune system rejuvenation- aged immune cells are removed, altered to a youthful state and reinstated to invigorate the sys-tem; super antioxidant genes- cells that could be ?coaxed? to produce another defense against dangerous molecules that ravage the body; resetting the cellular clock- when cells have access to a protein call telomerase, they lengthen the telomere tips of their DNA and live indefinitely; protective hormones- growth hor-mones, estrogen, and testosterone, while abundant when young, can help fight aging later in life; blocking blood sugar damage- glu-cose binds protein together into a ?gunk? that ruins organs, nerves, and tissue, new drugs could prevent the blobs from form-ing (Fischer 59). With all of these possibilities, one will change the lives of many people. All are giving people a hope and a dream that the living people will live longer than what their parents did. Living longer and healthier is definitely in reach for all in the future. With everything being learned from research, a longer life expectancy average will most definitely rise. Tech-nology will also be playing a big contributing factor. There is no doubt that biology will reshape and help to lengthen the lives of people in the future. Gregory Stock put it best by saying, ?We?ll double the human life span, but this will be a small part of all that will happen? (Fischer 58). Immortality is a goal for many people. With all the research being done, one is bound to let us live for as long as we choose or until our luck runs out.