Why do we age?

[butterbut]

Why after we turn 20 or so does our body basically flip a switch and start to slowly kill itself. Whats the advantage?

[triad]

Population control would be the advantage, but that is not why the body ages.

All living organisms on Earth dies eventually. Humans have relatively short lives, our lifestyle dictates our death rate. However, if we all lived forever - the planet would not be able to support all life. You get your 100 years (give or take) and then you make room for the next generation of our species. Make your mark in that 100 years, don't just be a carbon footprint that sucked life from the planet and did nothing good for it. GET OUT THERE.

[jose]

Who would have thought that the secrets to long life might exist in the naked, wrinkled body of one of the world's ugliest animals? Probably not many, but current research may be leading seekers of the Fountain of Youth to a strange little beast — the naked mole rat. The naked mole rat is certainly not one of nature's cuddliest species. These small rodents are hairless, wrinkled, blind and buck-toothed. Stan Braude, Ph.D., lecturer in biology in Arts & Sciences at Washington University in St. Louis, however, is attracted to these animals and has been studying them for over 25 years, with about 20 of those years being in the field in Kenya.

ScienceDaily: Ugly Duckling Mole Rats Might Hold Key To Longevity

[Thanatos]

Quote by: jose ScienceDaily: Ugly Duckling Mole Rats Might Hold Key To Longevity

Some of the "hottest" research on naked mole rats today concerns senescence, or aging. Naked mole rats in the lab have reached up to 28 years of age. And it's not just the controlled environments of their captivity that are doing this. Braude has observed mole rats in the wild that are 17 years and older. But these are the breeders. Lab researchers didn't realize that in the wild workers only live two or three years.

There's your secret. Breeders. In the past and even in some third world countries most people don't live past 35 and never get a chance to go gray or go through menopause. In humans this limiting factor tends to be starvation or war or plagues (or predators in antiquity) and nobody is immune. There's no incentive to keep things maintained because very few get a chance to die or otherwise stop reproducing from lack of maintenance.

In the mole rat, the breeders are effectively living in a well-guarded bomb shelter. If something manages to kill them it probably took out the whole colony. Pulsed metabolism is a beautifully simple reaction to this lack of major threats besides starvation and age.

[Kuldeep]

Aging is a natural process. Time passes thus, anything gets aged and increases further as time further passes...very simple and rational I think so.

Apart from time factor, nature has processes moving most of them in cycle:
In any material, living being in particular four, stages are obivious:

appearence, growth, derioration and extinction

Well, we know the basic element for survival or existence of life is oxygen. Growth is due to oxygen and so is the deterioration. So to reduce aging, one need to reduce oxygen in take.

Probably in past, Hidu saint controlled their breath in various pranayamas techniques to reduce oxygen intake and reduce aging and thus, lived longer !!!

Based on this theory, I think reducing agents should work as anti-aging agents, which could help in checking cell-deterioration and increase our life span. Research in this field must be interesting and beneficial. Or, at least is worth stydying !!!

[Capitalist Pig]

By the time you're 20 years of age, your face is a second generation copy of its original self.

That is, your cells in your body are constantly regenerating themselves. The problem is, each successive generation is poorer in quality than the previous. Every copy has a defect, that was not present in its predecessor, and little by little you're losing information at the end of the DNA. Eventually, the entire end segment of your DNA that deals with replication is lost, and your cells can no longer regenerate. Thus, death by old age.

With lifestyle, disease, congenital defect, and other factors, your mileage may vary.

[Kuldeep]

This sounds more scientific ! But do you mean that by the age of 20, the next generation cell is better than the previous one so that net result is the over all growth in the body. Then, a period arrives when next geration cells are as good as previous cells. On further aging, the inferior cells start getting replicated !!!

What is the approximate duration of one generation getting changed to next generation ????

I think it is a bit different !! The cell formation and dying is a continuous process. During growth period rate of cell formation is much more than than its destruction while; this rate reverses during old age.

But then, my idea of oxidation affecting this rate reversal of cell formation/decaying must have some role to play !!!!

[ZNFYRH]

We age because, at the cellular level, we become full of dead garbage.

Our hearts are no longer full of young and healthy cells, but have to labor around the dead cells that have accumulated, for example.

[Capitalist Pig]

Quote by: Kuldeep This sounds more scientific !

It is. It has a scientific name, too: Organismal senescence.

I should add that your environment plays a role in determining lifespan, as well. Stress is an important factor with aging, since it tends to increase the process exponentially. This is a problem for the average human, since in middle age, we tend to be under the most pressure of our adult lives (kids, mortgage, finances, career, medical problems, other responsibilities, etc). In nature, stress would correspond to the threats imposed by your natural predators and the scarcity of food sources.

So don't take my post above as anything but a gross simplification of the aging process.

Quote by: Kuldeep But do you mean that by the age of 20, the next generation cell is better than the previous one so that net result is the over all growth in the body. Then, a period arrives when next geration cells are as good as previous cells. On further aging, the inferior cells start getting replicated !!!

What I mean is that each time the DNA must repair itself from practically scratch, there is the increased opportunity of introducing a mutation during the repair process. Most DNA repair mechanisms do not have this risk, and are actually quite good at reversing the damage. This sort of damage repair mechanism, known as translesion synthesis, is only used as a last resort for the DNA repair machinery. Consequently, it is still possible to age without the rate of mutation increasing, so again we turn to a combination of factors.

Quote by: Kuldeep What is the approximate duration of one generation getting changed to next generation ????

Well, I go by decades of life (10, 20, 30, etc). The actual rate in any one individual human or populations of humans is bound to vary wildly.

Quote by: Kuldeep I think it is a bit different !! The cell formation and dying is a continuous process. During growth period rate of cell formation is much more than than its destruction while; this rate reverses during old age.

I wouldn't know, but considering the older you are the more information that has been lost, the more chance there has been for permanent damage to occur, it's possible.

Quote by: Kuldeep But then, my idea of oxidation affecting this rate reversal of cell formation/decaying must have some role to play !!!!

Well, sure, oxidative deanimation is one example of DNA damage.

[Praxius]

I was going to mention that the major reason for death of old age is our addiction to oxygen throughout our lives, as the oxidents gradually breakdown our DNA, which in turn makes us age.

A few reports I have read and watched talk about how high levels of Calcium can saturate your DNA and not only protect your DNA from Oxidents, but also can regenerate and rebuild your DNA.

I've been looking for the original article I read on this, and how a high concentration of calcium in your blood system is directly related to the speed in which you age, but it's been a few years now and I have not been able to find it easily.

[Jack]

Nature has a sponsored feature on this topic: Ageing: Collections : Supplements : Nature

[Capitalist Pig]

Quote by: Praxius I was going to mention that the major reason for death of old age is our addiction to oxygen throughout our lives, as the oxidents gradually breakdown our DNA, which in turn makes us age.

Yeah, it can be said that oxygen is a poison which is slowly killing us all.

[Kuldeep]

Quote by: Capitalist Pig Yeah, it can be said that oxygen is a poison which is slowly killing us all.

Oxygen is the cause of our life as well as death. What strange irony !!!

I once again recommend reduced oxygen through technique of Pranayama, old Hindu technique of breath control. Also use of some "NOVEL reducing agent" to reverse oxidative action of oxygen on life saving RNA. Researchers should find out whether it is possible !!!

Thus, chance of increasing average human life span by 50% if not 100% becomes a reality.

[thx1138]

How boring life would be to keep the same set of clothes through out your recycling periods. You don't want to muddy up your duds by eating to much junk, but rest assured you'll be getting a new suit every 85 years or so.

I'm hoping to be a Seamstess my next time around.

[CyrusTheGreat]

I Think , This dependence To Type and strike We , With Our Body , If You In Your life , do Sport forever , Your Body stand To Good type , even in 70 Age!

[Athena]

Quote by: Thanatos Some of the "hottest" research on naked mole rats today concerns senescence, or aging. Naked mole rats in the lab have reached up to 28 years of age. And it's not just the controlled environments of their captivity that are doing this. Braude has observed mole rats in the wild that are 17 years and older. But these are the breeders. Lab researchers didn't realize that in the wild workers only live two or three years. There's your secret. Breeders. In the past and even in some third world countries most people don't live past 35 and never get a chance to go gray or go through menopause. In humans this limiting factor tends to be starvation or war or plagues (or predators in antiquity) and nobody is immune. There's no incentive to keep things maintained because very few get a chance to die or otherwise stop reproducing from lack of maintenance. In the mole rat, the breeders are effectively living in a well-guarded bomb shelter. If something manages to kill them it probably took out the whole colony. Pulsed metabolism is a beautifully simple reaction to this lack of major threats besides starvation and age.

The doctor on Oprah said men need sex 4 times a week. :)

[Athena]

Quote by: thx1138 How boring life would be to keep the same set of clothes through out your recycling periods. You don't want to muddy up your duds by eating to much junk, but rest assured you'll be getting a new suit every 85 years or so. I'm hoping to be a Seamstess my next time around.

Well we may not get new bodies, but I am preparing for one. It sure makes my later years more fun to learn as much as I can, thinking in an unknown future this learning might pay off. Learning is more fun when we already know something, because the more we know, the more we can learn. Besides, I was born with a defect and age hasn't improved my condition. I am looking forward to a new body or a better medication that doesn't do terrible things to our body, like kill us prematurely. :)

One more thought. Who has such a perfect life, s/he would want to live it an eternity? That doesn't sound good to me.

[Praxius]

Quote by: Capitalist Pig Yeah, it can be said that oxygen is a poison which is slowly killing us all.

I like to think of oxygen as the ultimate drug that we are all addicted to. We need it to survive, yet in the end, it gradually rots us away and we die because of it (In most cases)

Which kind of begs the question that if oxygen has the same traits of addiction of drugs for a long period of time.... where do we as humans have the right to dictate to one another what actual drugs we can and can not use due to health concerns?

Seems a bit hypocritical to me when you really think about it since we're currently dieing from the same thing that provides us life.

[Sweet Katie]

Quote by: butterbut Why after we turn 20 or so does our body basically flip a switch and start to slowly kill itself. Whats the advantage?

We age because we haven't figured out how to travel faster than time. When Revlon figures it out, we'll be right as rain! :)

[Alive]

I think most of you are answering the question "how do we age" not "why do we age." The latter is a very different question. Life clearly has the capacity to sustain itself indefinitely--we happen to do so through reproduction, but there's no reason the same methods couldn't work to keep a single being alive for the same amount of time. The real question, then, is why haven't we evolved to not age?

Presumably there is some fitness advantage in creating more children in a shorter time rather than living longer--that is, it's cheaper to have an additional child now, who will have a child in a generation, rather than waiting a generation yourself and start having more children again yourself. I do not know why this is so, but it's the way we should frame the question.