AskMags.com

By Michael Quick

I had the great opportunity to sit down with Dr. Hunter for dinner the other evening, and afterwards and learned some VERY interesting things about hair.

Hydrogen bonds are the ionic bonds in the hair that give it strength and literally hold it together. They do not exist when the hair is wet. (Makes sense as this is why a style is washed out of the hair when it gets wet.) This is why hair is weak when it is wet. This is also why hair stretches much more when it is wet. Converselywhen the hair is dried the hydrogen bonds are rebuilt and the hair becomes stronger.

Building on this knowledge, hydrogen bonds also don't exist when dry hair is heated. The is why a curling iron works only when hot or a flat iron only works when hot. The heat breaks down the hydrogen bond and then as the hair cools the bond is reformed.

Now here is where it gets interesting...yeah I know FINALLY
It isn't heat that damages hair! You can place hair in a 450 degree oven and it will be fine. As hair dries the frictional damage actually increases as you are drying it. It is most severe when the hair is almost dry. This is the point the damage actually spikes. (think about it..this is when you get the most tangles in the hair as well) This frictional damage is so severe because at that point the heat has eleminated the hydrogen bonds and the hair is very susceptible to over stretching and frictional damage.

Moral of this is simple: Do not over stress the hair by pulling or stretching when using any heat appliance or round brush. To straighten hair you are muchbetter onthe hair to dry it wavy and gently flat iron it, than to pull and stretch it straight with a round brush..and as Mags has mentioned before be careful with bar bristle brushes as the boar's hair cuticle can tear at the human hair (Which remember is already fragile due to the bonds being broken)

This is why years ago (up to the late 60's), even with no protein treatments the DP blonde women had such pretty hair. They were set with rolers and placed under a dryer so no frictional damage occured as the hair was dried.

__________________
Michael Quick
Color Expert for AskMags.com

Mags's added info to this post:
I worked with Dr Hunter at the lab at Redken and he is a "Book of Knowledge" .
What Michael said is very true, that is why it's good also to dry perms under a dryer then use a curling iron on them.
I tell my clients that "have to" dry their hair with a brush to wait till it's dry, get their make-up on ,get dressed and by then the hair should be dry enough to take a brush to it, it has to be dry before you go to stretch it like Dr.Hunter/ Michael said.
In the Trichology section I have pictures of what a melted cortex looks like, so leaving heat too long IS damaging, but the real and most often damage is done when some of the hair is damp & some dry, they actually can pull against each other, the damp hair still stretching but the dry harden hair doesn't move, but the client with the brush or the stylist will not know that they are hurting the hair, but haven't all of you heard a hair snap?
Nozzles on blowdryers are very helpful too, learn to work with them as they help to keep the hair together so every hair drys at the same time.
Always use a heat protectant spray too as this helps the heat to seal down the cuticle making the hair shiner when curling or flatironing.