Changing Your Natural Look: Dyeing and Processing

More than half of people over age 50 have gray hair, but you’d
never know it. More people dye their hair to look younger than
do any other age-defying beauty enhancement. But if you want to
keep your hair as long as possible, it pays to be careful with dyes,
because improper use of dyes can do permanent damage to
your hair.
Graying generally starts at the temples and then spreads to other
parts of the scalp. Contrary to urban legend, your hair can’t turn
white overnight, although it may seem like it does when you let too
much time elapse between coloring!
Dyeing your hair can take years off you — but it can also be bad
for your hair. Plant-based dyes such as henna are less likely to
cause irritation, but the color doesn’t last as long as if you use
chemical dyes.
Most commercial hair dyes today contain the chemical para-
Phenylenediamine (PPD) as an active ingredient. It’s not uncom-
mon to develop skin sensitivity to permanent dyes containing PPD,
so be sure to test the product on a small area before covering your
whole head with hair color for the first time. Always check for the
presence of PPD in the dye that you are going to use. Even though
semi permanent dyes are not supposed to have PPD in them, never
assume this for your own safety.
There are two types of patch testing for PPD:
 Apply a 20-percent dilution of the dye being tested to a small
area on your neck below the collar; wait a full 72 hours to see
if there’s a reaction, which would mean a sensitivity to PPD. A
reaction produces a reddened, rashy, or inflamed area of skin
in the area covered by the test solution.
 Apply a patch containing a 2 percent concentration of PPD in
a petrolatum base to the skin and leave it there for up to three
days. If a rash or reddening occurs, remove the patch.
Sensitivities may arise even if you’ve been using a dye containing
PPD for years, so not being sensitive initially to the PPD doesn’t
mean that you won’t become sensitive to it over time.