Here's something else I found:
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The Elements & Moisture
Have you ever noticed that your hair appears longer, frizzier and more elastic during spring/summer months? Well for those who live in humid climates, your chosen location is probably why. Our hair becomes longer in higher humidities and shorter in lower humidities.
So the next time you're complaining about how "thick" the air is with humidity, take stock of what's going on with your hair. Generally, curly hair frizzes up while straight hair losses style and goes limp. Believe it or not, by going from dry to humid climates, your hair can actually change in length by as much as 3 percent.
Now you know why your hair appears shorter even though you haven't changed routines or had a cut.
Why Does My Hair Act This Way When It's Humid?
Well it's time to get a little technical. You've all studied the Anatomy of Hair section right? Then you know that hair is made up of keratin. Keratin is a coil-like protein.
Now for a hot second, try to remember being in Jr. high school (middle school for us young folks) and picture yourself in science class. Go back...go back...wow, some of you are taking a mighty long time to get there
The coils/turns found in keratin are held together by polypetide and hydrogen bonds. The polypetides provide strength and are difficult to destroy. Hydrogen bonds on the other hand are relatively weak and break down in the presence of water (H2O).
When the air is "thick"-humid or you wet your hair, the H-bonds break and allow the coils to stretch and as a result your hair lengthens. As your hair dries, the bonds reform.
I can hear so many folks out there going "oooooooooooh."
See, now you know why we suggest styling your dreadlocks and hair while it is still damp. Doing so will minimize stress and breakage because while wet, your hair can withstand the manipulation of the stretching (see Is Your Hair Healthy to the right).
Hair & Moisture
Ok, on a humid day what's the first thing that people with straight/relaxed hair reach for? Hair spray, gel or some styling aid that will keep the hair from going limp or frizzing up.
The application of product to your hair coats the cuticle layer. By constantly coating our hair with product, we inhibit the natural infusion of moisture resulting from humid conditions. So, by applying too much product, the protection you meant to supply your hair actually results in damaging it.
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