Feeds

Why do your hands turn white when you wash the dishes?

Shrivelling skin

Secure remote control for conventional and virtual desktops

Also in this week's column:

Why do your hands turn white when you wash the dishes?

Asked by Erin West of Oyster Bay, New South Wales, Australia</small

Human skin is made up of three layers. The outer layer is called the epidermis. "Epidermis" is from the Greek words "epi" meaning "on" and "derma" meaning "skin". It is a tough protective layer that contains melanin. Melanin both protects skin from the sun and gives skin its pigmentation.

Under the epidermis is the second layer called the dermis. It contains nerve endings, sweat glands, oil glands, and hair follicles.

Beneath the dermis is the third layer composed of subcutaneous fat. "Subcutaneous" means "under the skin".

Human skin is quite different in thickness in different areas of the body. The skin on the palms, fingers, soles, and toes is somewhat thicker than in other places. Skin colour becomes white from the opaqueness produced by the increased water content of the skin. Skin that has been submerged under water, such as your hands when washing dishes, appears wrinkled and shriveled up too.

Most people believe that this appearance is due to the skin shrinking. Quite the opposite is the case. The skin is actually expanding from the absorption of water.

Water is absorbed by skin immersed in water through the process of osmosis. This is because the internal body fluids of humans are more concentrated than in fresh water. Skin whitening, wrinkling and shriveling up appear because these areas of thicker skin expand as they become saturated.

Skin elsewhere on the body soaks up water after prolonged immersion. However, because this skin is thinner, there is more room for moisture, and the whitening, wrinkling, and shriveling up takes longer to appear.

Interestingly, the whitening, wrinkling, and shriveling do not occur from ocean salt water. This is because sea water is very similar to the fluids in the human body and osmosis does not take place.

Interesting facts

  • The skin of the average adult has a surface area of between 1.5 and 2.0 square meters. Most of this is between 2mm and 3mm thick.
  • The average square inch of skin holds 650 sweat glands, 20 blood vessels, 60,000 melanocytes, and more than 1000 nerve endings.

Stephen Juan, Ph.D. is an anthropologist at the University of Sydney. Email your Odd Body questions to s.juan@edfac.usyd.edu.au

Beginner's guide to SSL certificates

More from The Register

next story
Bond villains lament as Wicked Lasers withdraw death ray
Want to arm that shark? Better get in there quick
Renewable energy 'simply WON'T WORK': Top Google engineers
Windmills, solar, tidal - all a 'false hope', say Stanford PhDs
Antarctic ice THICKER than first feared – penguin-bot boffins
Robo-sub scans freezing waters, rocks warming models
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
Reuse the Force, Luke: SpaceX's Elon Musk reveals X-WING designs
And a floating carrier for recyclable rockets
The next big thing in medical science: POO TRANSPLANTS
Your brother's gonna die, kid, unless we can give him your, well ...
NASA launches new climate model at SC14
75 days of supercomputing later ...
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
Your PHONE is slowly KILLING YOU
Doctors find new Digitillnesses - 'text neck' and 'telepressure'
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Getting started with customer-focused identity management
Learn why identity is a fundamental requirement to digital growth, and how without it there is no way to identify and engage customers in a meaningful way.
Driving business with continuous operational intelligence
Introducing an innovative approach offered by ExtraHop for producing continuous operational intelligence.
5 critical considerations for enterprise cloud backup
Key considerations when evaluating cloud backup solutions to ensure adequate protection security and availability of enterprise data.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?