Know your hair’s porosity
“The porosity level, or the ability for your hair to retain and absorb through the cuticles of your hair shaft, is key when determining what products and routines to adopt for your curly hair,” says Story. If you don’t know what your hair porosity is, check out this hair porosity quiz.
Low-porosity hair has cuticles that are tightly packed and don’t allow for moisture to be easily absorbed, which is why heavy products and oils tend to build up on the outside and weigh down your curls. If that sounds like you, stick with lightweight shampoos and oil-free hydrators, like hyaluronic acid and aloe vera, and make sure to clarify once or twice a month with a sulfate-based clarifying shampoo once to break down buildup from silicones and waxes.
High-porosity, on the other hand, has raised and open cuticles, which pulls in moisture like a sponge but loses it fast, meaning it’s prone to feeling dry and prone to breakage. It can be genetic, but can also be caused by damage from color or chemical treatments, excess heat styling, chlorine, and sun exposure. You should try washing with a sulfate-free shampoo once or twice a week that’s filled with the heaviest oils (see: castor oil and coconut oil) to really seal in hydration and swap in a moisturizing co-wash every three or four washes to avoid over-stripping.
Check for sulfates
Pay attention to what type of surfactants (cleansing agents) are in your shampoo, which can be found in the first four to five ingredients on the label. In general, unless your curls are in need of a clarifying rinse to break down buildup, you should avoid shampoos that contain harsh sulfates—like sodium lauryl sulfate, ammonium lauryl sulfate, and sodium laureth sulfate—because they can dry out your hair and irritate your scalp. If you need a handy-dandy list of good vs. “bad” surfactants to crosscheck your shampoos against, I personally use this cleaners list by Curlsbot.