Jul 22, 2010 3:39 PM by Bea Karnes, News First 5
Researchers in Denmark are warning that hair dye products may be more dangerous than first thought.
Danish researchers said that after numerous tests of common supermarket permanent hair dye products they found that they can cause an allergic reaction and even harm the user's immune system.
The lead researcher says that hair dye can cause cell hormones to be released which, long term, can cause harm to the immune system.
An estimated five-percent of hair dye users in Denmark broke out in an allergic reaction shortly after using the product.