http://www.ck12.org Chapter 1. Human Biology
Of course, showering every day keeps you feeling and smelling fresh. But keeping clean is also good for your health!
For example, a shower or bath washes away bacteria and viruses that could harm you.
Keeping Skin Healthy
Your skin is your largest organ and constantly protects you from infections, so keeping your skin healthy is a good
idea.
Avoiding Sunburn
Some sunlight is good for your health.Vitamin Dis made in the skin when it is exposed to sunlight. But getting too
much sun can be unhealthy. Asunburnis a burn to the skin that is caused by overexposure to UV radiation from
the sun’s rays or tanning beds.
Light-skinned people, like the man pictured below (Figure1.8), get sunburned more quickly than people with darker
skin. This is because pigments in the skin act as a natural sunblock that help to protect the body from UV radiation.
Children and teens who have been sunburned are at a greater risk of developing skin cancer later in life. Long-term
exposure to UV radiation is the leading cause of skin cancer. About 90 percent of skin cancers are linked to sun
exposure. UV radiation damages the genetic material of skin cells. This damage can cause the skin cells to grow out
of control and form a tumor. Some of these tumors are very difficult to cure. For this reason you should always wear
sunscreen with a high sun protection factor (SPF), a hat, and clothing when out in the sun.
FIGURE 1.8
Sunburn is caused by overexposure to
UV rays. Getting sunburned as a child
or a teen, especially sunburn that causes
blistering, increases the risk of developing
skin cancer later in life.Keeping Clean
Keeping your skin clean is important because dirty skin is more prone to infection. Bathing every day helps to keep
your skin clean and healthy. Also, you know that taking a bath or shower helps prevent body odor. But where does
body odor come from? During the day, sweat, oil, dirt, dust, and dead skin cells can build up on the skin surface.
If not washed away, the mix of these materials can encourage the excess growth of bacteria. These bacteria feed on
these substances and cause a smell that is commonly called body odor.