There is always so much to learn about hair, especially if you're going natural. Even those of us that have been natural for years are still learning (well, I can only speak for myself—I have several questions), which leads me to the conversation about hair porosity. I see this topic talked about a lot, and I wanted to get detailed information from a curly hair guru on the subject. So, I turned to curl specialist, Marissa Rullan of Studio 210, to learn how to find out hair's porosity, what to look for on our product labels, and why healthy hair always starts in the shower. Keep reading for Marissa's tips on how to care for and create juicy curls each wash day.
Meet the Expert
Marissa Rullan is a curly-hair specialist who helps educate clients on how to properly care for and manage their curly hair. She began her career at Ouidad in Santa Monica where she predominantly styled and cut curly hair as well as styled hair for red carpet events. She's currently a stylist at Studio 210 in Los Angeles.
Before we get into finding out what porosity our hair is, I think we need to understand what that term actually means. "Porosity refers to how open or closed the cuticle layer is, which is the outermost layer of hair," Rullan explains. "Higher porosity hair has a very open cuticle layer with more gaps, while low porosity hair is moisture resistant because the cuticle layer is so tightly closed that water molecules are too big to penetrate the hair shaft, so the water just beads up and rolls off of the hair rather than absorbing into it."
How to determine your hair porosity
Curious how to test your own hair's absorbency abilities? Rullan says there are three ways to do so: the sink or float test, the spray bottle test, and the slide test.
For the sink or float test, "You'll take a few strands of hair that have naturally shed from the scalp and fill a cup with room temperature water," Rullan explains. "Remember, hot water opens the cuticle, so if the water is too hot, regardless of the porosity, the hair will load up with water and sink. High porosity is so open; the hair will quickly absorb water and then sink to the bottom of the cup. Low porosity hair is water-resistant, which means the strands will remain floating towards the surface even after a few minutes. If the hair hovers in the middle, you have medium or (normal) porosity which absorbs and retains water well."
Next is the spray bottle test. "You'll simply mist a section of the hair and closely watch," instructs Rullan. "If the water beads up and fails to absorb, maybe even rolling off of the hair after a few minutes, you have low porosity hair."
The final test is the slide test, which is to be done on dry hair. "Take a strand of hair and slide your fingers up the hair shaft towards the scalp in the opposite direction of the cuticle layer. If you feel tons of bumps, likely, you have high porosity hair."
Curious if an at-home test would yield accurate results, I asked Rullan how error-proof the methods are. "The water test is technically very accurate," she says. "However, just like different parts of the face, such as the T-zone, vary in oil production and collagen, the scalp reacts the same way. You may notice spots that are drier with a variation in curl pattern and porosity." As a curly girl, I can relate since the curls at the crown of my head are tighter than the coils toward the back of my head.
How do you care for different hair porosity types?
"High-porosity hair frizzes out when exposed to humidity and becomes more easily dry and brittle in dry heat," says Rullan. "Low porosity hair is moisture resistant because the cuticle layer is so tightly closed that water molecules are too big to penetrate the hair shaft." In other words, moisture is the key no matter your hair's porosity; look for products with emollients—or softening ingredients such as aloe, avocado, jojoba oil, and shea butter—as they form a barrier and trap water.
I have learned from many curl specialists that healthy hair starts in the shower because "water is life" as one stylist put it to me, and Rullan agrees: "Think of shampooing as a little less about cleansing the hair more about cleansing the scalp. Yes, it is important to care for the existing tresses, but a clean, healthy scalp is what produces healthy hair. On that same note, just like with skin, whatever you put in your body is more important than what you put on it so drink lots of water and maintain a nutritious diet."
Rullan also recommends all hair types always use a sulfate-free shampoo, as sulfates can be quite drying.
Two of Rullan's tried and true wash products are Ouidad's Cleansing Oil Shampoo and Triple Treat Deep Conditioner because they are packed with hydrating ingredients formulated with microtechnology that are steam-activated in the shower. For those of us with drier hair, she recommends pairing your shampoo days with your mask or treatment day because, as she puts it, "No matter the porosity, the essential goal with styling is to aid in water retention creating a shiny, juicy curl."
As for styling, Rullan says moisture-locking products are best. "We want to trap in as much water as possible. Squeeze out excess moisture before applying product but don't towel dry. With low porosity hair, steam from the shower is helpful, so use that to your advantage." She recommends applying products like Camille Rose Curl Love Moisture Milk or Ouidad's Curl Immersion Custard in the shower liberally for best results.
Rullan left us with a few gems at the end of our chat: "If definition and moisture retention are your priority, twists, braid-outs, and Bantu knots are the way to go. These sets help trap moisture in and allow more time for the hair to slowly but surely absorb moisture."
Lastly, she adds, "Sometimes, when people decide to embrace their natural texture, they assume it will be easier. Although natural is healthier, it's not necessarily easier—in fact, for some, it may imply more work. Rest assured the work is worth it for happier, healthier hair. You get out of it what you put into it."
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