Friday, 1 July 2011
If you were ever in a swimming pool or bath-tub for an extended time, you’ll know that your fingers wrinkle and end up looking like a raisin.
Do you know why?
We normally connect “shrivelling” to something that has shrunk or been dehydrated.
This is quite different.
The finger as actually expanded, due to being water-logged.
Our fingers have a substance called “sebum”. This oily substance can be seen on a mirror after we have put our finger-print on it.
One of the jobs sebum has is to keep water out of our skin.
However, when we spend a lot of time in the water, that sebum gets washed off and water then gets absorbed into the outer-layer of skin (called the epidermis). As the layer of skin absorbs the water it expands. However, since certain points of that epidermis layer are tied down to another layer called the “dermis”, it expands more where it isn’t tied down. This is where the ‘wrinkled look’ comes from.
So, the wrinkles are not caused by any shrinking or shrivelling-up, but from swelling.
Thankfully, soon after getting out of the water, the excess water evaporates and the body replaces the sebum to continue its work.