How and Why Do We Age?

You've changed lately, you look different now! I don't recognize you lately! 

It's as if something has changed in you today, how can I put it, something has changed in you today! 

Did you cut your hair?

Or did you dye it? Or maybe you combed it in a different way!

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We are born, certain memories are imprinted in our memory, we continue to live, some memories are erased and new ones are added.

As soon as we are born, some of our cells start to die, although new ones are formed in their place, or many of them divide and multiply anyway.

In the end, we grow, we get bigger.

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So at which stage of our lives do you think we are the original us?

We are in a constant state of change. 

We are not the same in our memories, nor is our body made up of the same cells as the first day.

Yes, we all have our own unique character. 

These character traits are formed both by the genetic traits we inherit from our families and by what life brings to us. 

We all develop biologically in accordance with a code we call DNA, and with this code, we actually live in a genetic cycle so that yesterday's us is similar to tomorrow's us.

But our DNA also changes slightly over time. 

We are getting older every day!

Why is this so?

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Cells divide a certain number of times during their lifetime. 

During these divisions, the DNA of our new cells is disrupted by certain errors, by the radiation we receive from the environment and for many other reasons.

More importantly, the DNA chain changes depending on the number of reproductions that were set from the beginning, in a sense, depending on a feature that we can call our genetic clock.

Telomere loss is the DNA sequences at the ends of our chromosomes.

These are lost every time the cell divides. 

Therefore, after a certain number of divisions, the cell cannot divide any more and dies.

Alexei Matveyevich Olovnikov, a Russian biologist working on these issues, is the scientist who discovered the telomere problem in cells in 1971.

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There are other scientists working on these issues.

A lot of work has been done on cells.

For example, a connective tissue cell cannot divide more than about 50 times. 

An embryo cell can divide at most 60-80 times. 

Some cells taken from a middle-aged person divide at most 10 times.

This information was found through timely studies.

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Leonard Hayflick, a professor of anatomy and biology, is another scientist whose work 35 years ago revealed this fact.

Hayflick wrote about his work in 1994 in his book "How and Why We Age".

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Indeed, even though the cells in our body have different lifespans, each cell has a specific lifespan. 

During our lifetime, most of our cells die.

We don't realize it, but in the end we are a colony of cells living in a colony. All cells live and die in a certain order.

In fact, the average lifespan of the cells in our body is said to be between 7 and 10 years.

Of course, this is the average cell life span. This average value is determined as an average according to different cell lifespans. 

For example, neutrophil cells (a type of white blood cell) in our blood have a lifespan of two days, while the cells in the center of our eye lens are with us for life. 

The lifespan of some of our brain cells is said to be even longer than our lifespan. 

In experiments on mice, it was found that the brain cells of mice live more than two lifetimes.

Some cells in our brains are also thought to live more than 200 years, but most of the cells in our brains have lifespans on the order of 10 years.

Of course, in some of our cells this is well below the average, while in others it is well above.

For example, heart muscle cells live 40 years, intestinal cells 16 years, muscle cells 15 years, fat cells 8 years, stem cells that produce our blood 5 years, liver cells 10-16 months and pancreatic cells 1 year.

But we also have cells such as white blood cells, many of which have a lifespan of a few hours, skin cells for example, which live for a week at most, and with other short-lived cells the average naturally drops considerably.

There are about 37 trillion cells in our body. 

Very few of these cells stay the same throughout our lives. The vast majority are in a constant state of change.

The cells that die are somehow removed from the body, or they are used as building blocks for cells that have to be produced in large quantities, such as white blood cells.

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Yes, this is the case! 

In our memory, information is transferred from one cell to another, so we live as us as far as we can remember.

But none of us is who we were born to be.

I wonder if one day a cure will be found and our life span can be extended.

For example, could we live forever by replacing cells whose time has expired without disturbing the body order?

Maybe!

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But until that day comes, for now life goes on according to whatever the established order is.

Let me ask you one more time, at which stage of our lives do you think we are the original us?

Are you sure that yesterday's you and today's you are the same person?

I am not sure.

With love and respect from Moscow.