Hair Porosity 101

Understanding your hair porosity can help you determine everything from what kind of products to how long your Color Depositing Mask shade of choice is going to stick around. The problem? It’s something many of us don’t know a lot about. To help you understand more about your own hair porosity and the impact it has on your hair health and styling decisions, we enlisted Moroccanoil Artistic Team member Michael Cohen to answer all your burning questions.

What is hair porosity?

“Porosity is the hair’s ability to absorb and retain moisture,” says Michael. Moisture, in this context, can refer to everything from the moisture in the air on humid days to water-soluble products you apply.

What can cause porous hair?

All kinds of things. According to Michael, “shampooing your hair too often, especially with the incorrect products for your hair type, chemical treatments like bleach, UV exposure without protection, and excessive use of heat styling tools” can all increase your hair’s porosity. “In some cases, very curly natural hair can be very porous,” he adds.  

How can you test hair porosity?

Yes! The best way is to ask your stylist to evaluate your hair porosity next time you’re in the salon. However, if you’re pressed for time, there are a few ways to test it at home. One way to do so is to take a strand of hair from your brush or comb and drop it in a glass of water. If it floats, your hair is likely low porosity and doesn’t easily absorb water. If it sinks slowly, your hair is normal porosity. And if it sinks quickly, you likely have high porosity hair that drinks up whatever moisture it comes in contact with.

What are the characteristics of low porosity hair?

“Usually, the hair takes longer to dry, and product tends to build up easily,” says Michael. With low porosity hair, “products don’t really penetrate at all.”

What about normal porosity hair?

Generally, “normal porosity hair absorbs and holds moisture well,” according to Michael. “The hair tends to be healthier and easier to maintain.”

And high porosity hair?

“Usually the older the hair is, the more porous it is.” (Long-haired ladies and gents, take note.) With high porosity hair, “the cuticle begins to crack, peel and lift away.” While those particular symptoms might harder to notice with the naked eye, it’s also why people with high porosity hair often experience excess frizz. So if you feel your hair frizzes easily, that might indicate that your hair is on the porous side.

What can understanding your porosity level tell you about what products to use?

“It’s very important to under your porosity level,” says Michael. “Using incorrect products will alter the intensity or effect that we are trying to create.” For instance, low porosity hair is prone to build-up and generally responds better to lighter, liquid-based products. High porosity hair, on the other hand, can handle heavier leave-in conditioners and moisture-rich products. (In fact, it needs them—high porosity hair loses moisture more easily.) It will also benefit from anti-humectants that keep it from absorbing the moisture in the air, which leads to frizz.

As a rule of thumb, just know that the more porous your hair, the more product it will absorb. That means if you’re trying a Color Depositing Mask, it’s likely that highly porous hair will absorb more of the product, leading to longer-lasting color.

What’s the best way to care for porous hair?

“If you’re dealing with porous hair,” says Michael, “try Moroccanoil Restorative Hair Mask to infuse protein into the cuticle of the hair. You can also apply Moroccanoil Treatment as needed to smooth the cuticle and increase elasticity.” Another thing that helps? Haircuts. Remember, the longer hair has been around, the more porous it likely is. “Cut your hair every 5 to 6 weeks to eliminate the older hair,” advises Michael.