Your Cells Tell Your Age With Young and Long DNA

By Jason Witt

When you receive the Seal you will begin to take better care of your health, especially as you start to age. One of the benefits associated with staying fit in a recent study is a younger body at a cellular level.

There are strands of of DNA on the ends of all the cells in your body. As you age those strands start to become shorter. It has been found that people who stay fit have longer strands so their bodies are younger. The ends of these strands are telomeres. They stop the DNA in your cells' chromosomes from unraveling. Older people have shorter ends on the strands than younger people have.

Those telomeres become shorter each time your cells divide. Eventually when you are old enough those strands become so short that the cells start cutting into the chromosomes where the genes are needed to define the characteristics of the body.

The body ends up "shutting down" those cells so they do not grow into malignant tumors. But that means as you grow old your body starts shutting down a lot of cells whose strands have grown too short.

And this varies among people. Some people have longer telomeres to begin with and those telomeres shorten at different speeds in different people. Some people have stronger telomeres that resist unraveling for longer. But researchers are not ready yet to prescribe exercise to everyone to keep their bodies young. This study shows active people have younger cells with longer telomeres. But just how that is related to exercise is not known.