Wednesday, May 19, 2010
Chemistry of your hair: Grey hair
Why does our hair go grey? The short answer - science really doesn't know. The long answer - it's a loss of melanin in the hair shaft. Why does this happen. Science really doesn't know.
I have to admit it amazes me that we don't know about 85% of the bacteria in our intestines, most of the components of garlic, and why we go grey, but we know how to send a lander to Mars and how to spot supernovae. Science is interesting, eh?
About 50% of Caucasians will have 50% grey hair by age 50. Greying can start as early as age 20 for Caucasian hair types and age 30 for African hair types. Although it is a normal part of aging, when it's found prematurely in younger people it is called canities, and can be caused by genetics, certain diseases and conditions (like vitiligo), or stress (although when it happens with stress the theory is that we lose more hair and any grey hairs become more obvious).
What we do know is grey hair tends to be coarser and more wiry than non-grey hair. And people with a lot of grey hair tend to need more moisturizing and conditioning because they tend to have reduced levels of sebum (although this has to do with age and not the grey-ness of their hair). Grey hair can be dyed, but it can't be reversed, unless it's something to do with a medical condition like hypothyroidism.
When you're formulating for someone with lots of grey hair - like my mom - you want to use gentle surfactant mixes and intense conditioners suitable for dry hair in an attempt to return some of the oils back to the hair and scalp. If you are formulating with someone with some grey hair, just go with their usual hair type because an oily haired, greying girl will not appreciate all those oils!
Should you dye your grey hair? That's really up to you. It may help reduce the wiriness of the grey hairs and will definitely make them less obvious.
I'm letting mine grey right now because I simply can't find time to do all that dying and re-touching of roots (plus three boxes of dye costs too much!) and I think it looks kinda cool, like blonde streaks in my lightish brown hair. (I also worked for a woman who had white white hair that went all the way down to her waist. It was beautiful, and she has become my role model for awesome hair!)
Dyes will show up better on grey hair, so you could have some fun with those colours that have blue or purple or pink highlights.
Remember the bluing little old ladies used to use? That's because the blue makes the white whiter. Unfortunately, a little too much blue makes you blue. I prefer to think of them as rebels who really wanted blue hair to show they were cool older ladies who could still rock out on the weekends.