How can we live longerIntroduction: I. Why do we age? Theories of agingII. What is longevityA. Lifespan and life expectancyIII. What determines longevityIII. Why Most Americans Don't Live Beyond Average Life ExpectancyIV. Main causes of death (table)V. What do we do to live longer? Conclusion: Introduction What is the fear of most humans? Fear is aging and death. In this article you will learn a lot about aging. You will learn what longevity is, what determines it, the average lifespan and how to exceed it. You'll find it amazing that doing simple things every day helps you feel better and live longer. Why do we age? As soon as we are born, we begin to die. That's life. No one knows how long they will live, but we can try to do everything we can to live longer. Aging is not controlled by anyone. Aging is a genetic process. We age until our bodies break down. What causes the breakdown, the decline of energy, the inability of the body to function. Nothing completely explains why we age, but there are a few theories that will help explain what's happening. Theories of Aging The genetic theory states that cells contain "aging" genes that indicate the exact number of times the cell can duplicate itself, for humans, approximately 110 to 120 years. Another theory suggests that the cells' DNA becomes defective after a certain point and synthesizes a defective protein. The fault disables normal cell function, causing the cell to deteriorate or collapse. Immune system dysfunction is a theory of aging involving the immune system..... .middle of paper ......book: Salem Press. A journal article McCartney, K. (1984). The effect of a quality daycare environment on children's language development. Developmental Psychology, 20, pp. 244-60. An article signed in a monthly magazine Beardsley, T. (1994). For whom the bell curve really rings true. Scientific American, January 1995, volume 272, number 1, pp. 14-17. An article signed in a daily newspaper Moore, M. (December 27, 1994). The speculation irritates Flores. American Journal, Section D, p. 1.An unsigned articleWhat Vietnam did to us. (1981, December 14). Newsweek, p. 46-97. A film or video tape Hand, D. (supervising director) and Disney, W. (producer). (1937). Snow White and the Seven Dwarfs. [Video tape]. Burbank, CA: The Walt Disney Company. Microsoft Works Computer Software for Windows 95 (1995). [Computer program]. Redmond, Washington: Microsoft.