Re: Why do bruises become black and blue?

Greetings, 


Most bruises occur as a result of your coming in contact with another 
object or person. As a result of the initial collision, you break blood 
vessels, which leak blood into areas under your skin causing swelling, 
discoloration and soreness. Bruises are most common in older people 
whose skin is thinning with aging. 
This is due to the fact that collagen, the connective tissue that cushions 
skin breaks down, leaving underlying blood vessels more vulnerable. People 
who take medications for diseases, including blood thinners like aspirin, 
also also have an increased risk of bruising.
A normal bruise should heal on its own within a few dayst to a couple of 
weeks.  As a general rule, bruises tend to heal more slowly as you go down 
the body.  In other words a bruise to the arm heals more quickly then one 
to the leg.
Bruises on the legs are often the worst, because there is more blood 
pressure in the leg vessels, so they bleed more than blood vessels in the 
arms.
 http://www.betterbodz
.com/library/bruises.html http://www.mayo
health.org/mayo/firstaid/htm/fa3d.htm http://www.umm.edu?uniq=5165

Thanks for taking the time to send in a question to the Mad Sci Network.

June Wingert
Mad Scientist