Why we age...

I think there are many facets that contribute to aging. I find all three causal theories of aging, "the good-of-the species theory, the rate-of-living theory, and the evolutionary aging theory," to be very intriguing. The book makes a great point about why each can be justified and disproved.  I have always felt that cell division plays a dominate role in aging. I feel this way because cancer is predominate in the world and it is a disease that results from mutations that cause uncontrolled division of cells. The risk of cancer increases as we get older in age. 


In Why We Age, on page 65, it talks about how some research suggests that "limited cell division may inhibit healing in arterial regions that have been damaged by being bombarded with blood. Also our immune system needs rapid, plentiful cell division to operate effectively." If cells don't divide properly, or target foreign cells (viruses) as quickly, it causes us to be ill longer and puts a lot of stress on the organs. I think that stress on the body can really age a person. This is seen often in people who hold stressful positions or undergo stress times in life, such as a parent dying. 


While this doesn't support my belief of aging, it is a very different explanation as to why we age. If you have never been on TED: Ideas Worth Spreading, you should check it out (www.ted.com). It's a website that has talks and performances from "remarkable" people all over the world. One lecture that is particularly interesting is a lecture that was given by Cambridge researcher, Aubrey de Grey. He argues that aging is a disease that can be cured. This is quite a statement and he has quite an extreme argument. Check it out at: http://www.ted.com/talks/lang/eng/aubrey_de_grey_says_we_can_avoid_aging.html.