AF Technical | Let's Talk Hair Porosity
It can be tricky to strike a balance between protecting your hair from damage and lightening it enough for coloring. Here at Arctic Fox, we're dedicated to helping you achieve your dream hair, so we wrote this article to explain an important hair care concept: porosity. Understanding and balancing your hair's porosity is important to get you beautiful, long-lasting color without frying your strands. So let's get to it!
Have you ever wondered what your hair looks like up close? It actually looks sort of like an elastic hair band! Like a hair band, your hair strands are made up of a strong and flexible core wrapped in a protective outer layer. The core of your hair is called the cortex, and it’s mostly solid keratin (the protein that your hair is made of). The outer layer is called the cuticle, and it is made of tiny scales of keratin, going all the way from your roots to your tips.
What is porosity?
Porosity refers to the hair’s ability to absorb moisture, and it depends on the structure of your hair. Hair that is not porous will not take on color well, but hair that is too porous will let it out quickly. A balance between the two is important for good hair color results!
Healthy, newly grown hair is not porous; it has neatly-layered cuticle scales that protect the inner cortex. This keeps in your hair’s natural oils and keeps out water, dye, and other substances. This protective layer is the reason why hair may not hold onto color well even if it's blonde; the pigment can't get inside! Hair needs to be treated to allow you to get the most out of a hair dye.
So what does porous hair look like? When your hair is exposed to heat and sun for too long, washed with soaps that are too strong, or gets treated with harsh chemicals, the outer cuticle loosens up. Those protective scales on the outside begin peeling up and sticking out. This lets water, dye, and other substances into your hair more easily. It also lets some of the natural oils out, which makes it more prone to becoming dry and scraggly.
Very porous hair
If your hair is too porous, the cortex inside can start to weaken. We all dread it; frizzy, weak hair strands that are always tangled up. When your hair gets too much damage, the keratin begins to break down opening gaps inside that let more water in and more natural oils out. If the strands are weak enough, you can even get split ends and breakage, which nobody likes.
It can be hard to judge how porous your hair is by just looking at it, but fortunately we have a few easy tests you can do at home to check on how your hair is doing!
TEXTURE TEST: The scales of your cuticles are too small to feel, but you can feel the resistance they give when you run your fingers along them. Hold a few strands of hair by the end and using the other hand, pinch the hair strands and run your fingers up and down their length.
If it slides just as easily up as it does going downward, the hair is not porous. The scales are laid flat so your fingers glide right along.
It may be very subtle, but the more resistance when stroking your hair backwards, the more porous your strands are.
STRETCH TEST: Remember when we compared hair to an elastic hair band? Well you can test the strength of your hair like one! Collect about 10 strands of wet hair shed after shampooing, hold them up against a ruler, and carefully stretch them.
- NON-POROUS: The hair stretches 30-50% and returns to its previous length.
- POROUS: The hair stretches but does not return.
- VERY POROUS: The hair breaks after stretching less than 30%.
FLOAT TEST: Since porosity is your hair’s ability to let in water, you can also use water to test it. Pull a strand of clean, dry hair off of your hair brush and drop it into a glass of water.
- NON-POROUS: The hair's natural oils are trapped inside, letting it float.
- POROUS: The hair lets water in slowly and eventually sinks.
- VERY POROUS: The hair lets water in immediately and quickly sinks.
Hair that is less porous will be more manageable and soft, but your hair may not hold onto color well (or at all!) if the cuticle scales are laid flat. The dye can’t get inside and will wash right off the surface.
Hair lightening products work by opening up the cuticle to bleach out your hair’s natural pigments. This will always damage your hair to some extent, but it will also allow you to get longer lasting, more colorful hair. With the cuticle scales open, dye can soak in and bind to your hair better. Since hair is weaker in this state, it’s good to use products that will nourish and hydrate your hair. Arctic Fox Hair Color is great for this, as it is formulated with a conditioning base that returns moisture to your hair!
You might think that opening the hair as much as possible will let it take on dye the best, but this isn’t necessarily true. If the strand is very open, water and soaps soak into it easily, washing hair dye out of the cuticle even more quickly. Even worse, some dye may get into the cortex, leaving behind pigment that will give your hair a tint long after the dye has washed out.
The best type of hair for coloring has a cuticle that is moderately porous. The cuticle lets in dye, but holds water out enough to keep the pigment inside. The cortex still has some of its natural oils, and stays strong enough to be easily manageable.
Hair color after 4 washes (by @weirdgalkarsen )
Protecting your hair
The word “damage” is often used to describe how hair becomes porous. While it’s true that your hair becomes damaged when you treat it, you shouldn’t be afraid to lighten your hair if you do it slowly and safely. It’s your hair to express yourself with, so you should do what you like with it! Also remember that even if you overdo it, your scalp will always make more fresh, strong hair.
With that, here are a few tips to avoid excessive hair damage and keep your hair in that ideal porosity range.
- UV LIGHT: The sun can damage hair slowly, so if you’re going to be in the sun for a long time, consider using a UV protectant or covering your hair to block out those powerful UV rays.
- POOL WATER: The chlorine in pools can react with your hair, weakening it. Your hair will recover from a dip in the pool of course, but avoid submerging your hair in the water regularly or for long periods to avoid lasting damage. (fun fact: it’s actually not the chlorine in pool water that turns hair green over time, it’s dissolved copper! Chlorine just opens your hair to let it in)
- SEAWATER: Minerals in seawater also damage hair. The salty water pulls moisture out of your hair, opening the cuticles and leaving it dry. Just like with the pool, avoid dipping your hair in often to avoid serious damage.
- HEAT STYLING: Heat changes the structure of protein, so heat styling tools will weaken the structure of your hair. Keep those hot irons away from your hair to prevent them from getting fried (or turn down heat settings to help reduce damage).
- HARSH SOAP: Good shampoos contain gentle soaps and protective chemicals to prevent too much natural oil from getting stripped off your strands. Use quality, sulfate-free shampoos to hold on to that healthy natural oil. Shampoo like this is also great for colored hair, as it doesn’t strip away pigments as much.
- NOT CONDITIONING: Any oils that your shampoo does strip away can be replaced by a conditioner. Both your natural oils and the ingredients in conditioners form a protective layer on your hair that protects against further damage.
- CHEMICAL TREATMENTS: And lastly, lightening treatments cause damage to hair as well. Your hair can recover well enough from a single application of bleach, even with a high developer volume, but take care when retreating hair! Hair that has been damaged by a lightener is even more susceptible to damage on reapplication, so if you need to touch up roots, keep the bleach off the length that has already been treated. If in doubt, talk to a stylist!
You probably see a lot of marketing for products that repair damaged hair. If your hair is very porous and damaged, these products can help restore it. Many products in our new hair care line contain a special ingredient called Polycare Split Therapy, which is designed to help bind broken, frayed hair back together. Other treatments, such as keratin therapy, can restore the cuticle somewhat and help seal your hair’s natural oils back in. Remember though that while products like this can help restore some strength and smoothness to hair, it’s impossible to permanently repair it. Nothing is as strong as newly grown, healthy hair, so always keep your hair’s health in mind!