How old are the cells in my body?

[Janet Duerr]

I have read estimates of 1 _trillion_ neurons in the human brain.  So
the number must be many times more than that for the entire body.

MF wrote:
> 
> How many cells are in my body?  Is it a consistent number?  Or does it
> fluctuate?  When a cell dies where does it go?  Does it deteriorate or stay
> in my body?  Are the cells in my body the same age as me?  Are all my cells
> also 27 years old?  Or are none of the cells I was born with still part of
> my body?  Have all my original cells died and deteriorate and been replaced
> by others?  Every single part of my body is made up of cells right?  If all
> the cells that I was comprised of when I was born have died have they been
> replaced by others and in a sense I am not physically the same person I was
> when I was born?
> 
> <http://www.biowww.net/forum/read.php?f=2&i=1173&t=1173>