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Why We Age - Theories and Effects of Aging

Humans have been aging for generations, but only recently have researchers begun to study aging seriously. There have been new developments in aging research and theories. Learn about why we age and what happens in our bodies during aging.
What is Aging?
Aging is a complex process that is only partially understood. Some people think that our bodies just wear out while others think that aging can be prevented or even reversed by replacing parts of our bodies or giving hormonal or other supplements. When we think about aging, we have to look at what happens to our body over time.
MIT's AgeLab
Aging research takes many forms from laboratory research on the aging of mice, worms and other animals to designing products to assist the aging. This second route is what MIT's AgeLab does. It has simulators for driving, walking and even a suit that help people understand what it feels like to be older.
Telomere Shortening - The Secret to Aging?
Telomere shortening is thought to be a major theory of aging. The cause of aging looks into what happens on the cellular level when cells divide. Telomere are shortened with every cell division, but some people's telomeres don't shorten over time, and no one knows why or what impact that has on longevity and aging.
The Sun's Effect on Life Expectancy
Your life expectancy may be shortened because of the sun. The ultraviolet radiation in peak solar years seems to be linked to shorter life expectancies (and not because of skin cancer). What does this mean for longevity and healthy aging? Find out more about life expectancy and ultraviolet radiation.
Is Aging in Your Genes?
Genes are an important part of how your body ages. If you have certain genes you will be more (or less) likely to develop health conditions like high cholesterol and diabetes. But how much do those genes matter? Find out more about genes and aging.
Senescence, Healthy Aging and Longevity
Senescence is the biological term for the decline associated with age. Senescence can take place on both the cellular and organism level. Slow the process of senescence to increase longevity and healthy aging.
Why We Age -- Theories and Effects of Aging
Aging is a complex process that researchers are only now beginning to understand. There are many theories of aging and many descriptions of what aging does to our bodies. The reality is that all of these processes interact in a complex way. By understanding aging theories and why we age, we can better take action to age in a healthy way and live longer.
How Sugar Makes Us Age - Protein Cross-Linking and Aging
As we age, the tissues in our bodies stiffen. This is caused by sugar molecules bonding with protein molecules. The result is that two protein molecules are stuck together, or cross-linked.
Telomeres and Aging - Understanding Cellular Aging
Telomeres are a DNA sequence that appears at the end of each chromosome. When cells divide, the telomeres get shorter. Eventually the telomeres are so short the cell can no longer divide. This triggers cell aging and death of the cell.
The Genetic Theory of Aging
The genetic theory of aging believes that the genes we inherit are the most important factor in determining how long we will live. While there is some evidence for this theory, it ignores our behaviors and exposures throughout life.
Free Radical Theory of Aging
The free radical theory of aging states that the damage caused by free radicals can, over time, create the changes we see in our bodies as we age. Consuming antioxidants by eating plants is the best way to combat free radicals.
The Somatic Mutation Theory of Aging
Somatic mutations are changes that happen to your genes during your lifetime. These changes are caused by errors and exposures but are not inherited. Over time, the somatic mutation theory of aging states that these changes accumulate, which causes the effects of aging.
The Immune System Theory of Aging
The immune system theory of aging believes that many age-related conditions are caused by a decrease in the function of the immune system over time.
Rate of Living Theory of Aging
The "rate of living theory" of aging says that your biological age is dependent on our rate of living. The faster your heart beats, your breathing occurs or your energy metabolizes, the more quickly you will age. This theory is one of the oldest theories of aging, but has little evidence to support it.
The Hormone Theory of Aging
The hormone or endocrine theory of aging puts forth the idea that hormones ultimately control the pace at which we age. Theoretically, by identifying the hormones that control aging, the process can be slowed. To date, no such hormones have been discovered.
Wear and Tear Theory of Aging
The wear and tear theory of aging believes that our bodies simply "wear out" due to all the damage and exertion caused by living. Over time, our body can no longer keep up with the damage being done due to exposures and physiological processes.
Programmed Theories of Aging
There are several programmed theories of aging, meaning that aging is programmed into our bodies. These theories assert that aging is an essential and innate part of the biology of people, and that aging is programmed into our body systems.
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