How long to "reinvent" yourself?

Back in the pop-psychology days of the mid 1970s, it was sometimes claimed that every cell in your body replaced itself in seven years. That "factoid" was used as the launching point for insisting that we have the ability to recreate ourselves every seven years from a clean sheet of paper.

I got to wondering about the veracity of the "...replaced itself every seven years..." factoid.

It varies by organ and by age  Source

Intestinal linings: Every 5-to-10 days

Taste buds: Every two weeks

Skin cells: Three weeks 

Lung tissue: Every two or three months

Joe notes: Cells that interface with the environment get replaced more often than cells that are complete surrounded by the immune system. 

Liver: Every 1.5 years with some types of cells turning over every five months

Kidney cells: Years 

Bones: Every 10 years

Skeletal Muscles: Life-time with the option to "recruit additional muscle cells" from a pool of satellite cells. 

Heart muscle cells: Decades

Central nervous system: Life-time with very limited regeneration. 

It is worth noting that if it takes your bones ten years to completely replace themselves then more than half of them will be "new" in seven years.

So...if you had to pick one number "seven years" is not a bad guess. And while you can quibble that our brains (CSN) define us and "it doesn't change",  I would counter with the fact that our brains constantly reprogram without liveware updates. They are designed to change without new hardware.

*A reference to a recent post by John Wilder on his blog.