Sciency Words: Hayflick Limit

Today’s post is part of a special series here on Planet Pailly called Sciency Words.  Every Friday, we take a look at a new and interesting scientific word to help us all expand our scientific vocabularies.  Today’s word is:

Hayflick Limit

If you dream of immortality, the Hayflick limit is your enemy.  In the human body, cells periodically die and are replaced.  Scientists used to believe that, barring sickness or catastrophic injury, cells could continue to reproduce themselves indefinitely.  They did not suspect that cell division could have anything to do with the aging process or natural death.  That was until a man named Hayflick came along.

The Hayflick limit is determined by the length of the telomeres (excess genetic material) in a cell’s DNA.  Think of it this way: when you tie a knot, you usually leave a little extra string to make sure the knot doesn’t come undone.  Telomeres are like that extra string, but every time your cells divide, your telomeres become a tiny bit shorter.  When a cell has no telomeres left, it has reached its Hayflick limit and can no longer create copies of itself.

We all know our bodies break down as we age.  The Hayflick limit is, if not the sole cause of aging, at least a major part of it.  So if you want to live forever or merely prolong your life for a few centuries, you will have to figure out how to lengthen your telomeres and increase the Hayflick limit of your cells.