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All hair is porous, but some hair is more porous than others -- and that's not a good thing. Thankfully, there are ways to combat porous locks that will help you keep your hair beautiful and healthy. Once you know the deal, there's no reason to let your hair's porosity rule your styling life.
To understand porosity, it helps to have a grasp of what your hair looks like under a microscope. Picture it: an individual strand of hair, also called the hair shaft, with tiny little scales all over it. These scales -- the cuticle layer -- are like gateways for your hair to let in chemicals and water as well as let them out. When the gates are slightly open, your hair absorbs easily. When the gates are closed, it doesn't. When the gates are wide open, your hair loses moisture rapidly and is easily damaged.
There are three rankings of hair porosity: high, medium and low. Highly porous hair means those gates are open and some of them are even broken. If this is your porosity level, your hair will feel straw-like when it's dry and sort of rubbery when it's wet. It's also likely to break easily and get damaged easily. Low porosity means the gates are shut up tight. This hair type usually has a lot of natural shine, which is good. It resists damage, but that doesn't mean it's invincible. If it gets damaged, it's hard to put moisture back into it. It also tends to resist hair dye and other chemicals. Medium porosity is the lowest maintenance type. The hair holds styles well, isn't overly dry and accepts treatments in a predictable way.
There are several factors that affect the porosity of your hair. It has a genetic component. It is also affected by whether your hair is straight or curly. The shape of a naturally curly shaft tends to create more open cuticles. Finally, excessive styling, dying, heat or chemical processing and product buildup can make your hair more porous.
If your hair has low porosity, it's probably healthy. If it starts to get dry and brittle, use a deep-conditioning treatment mixed with heat to open up the hair shaft. Tell your stylist that your hair doesn't take color well before you let him apply it. He'll know ways to help ensure that you get the effect you want. If you have medium porous hair, it's probably in pretty good condition. Just deep-condition it once in a while to maintain its health. If you have damaged, highly porous locks, focus on fixing the damage. Use hair masks, shampoos and leave-in conditioners that are moisturizing. Look for products that have the word "humectant" in the label. A humectant helps retain moisture.
The best thing you can do for your hair is to prevent damage in the first place. Avoid heat styling as much as possible and use a heat protector spray on wet hair before you style it. Comb tangles out with a wide-tooth comb, starting at the bottom and working your way up to the roots. Get your hair trimmed regularly. Treat your hair as gently as you would treat your most coveted, expensive and fragile wardrobe item.