Low porosity hair refers to hair that has a tightly closed cuticle layer, which makes it difficult for moisture to penetrate and be absorbed by the hair shaft. This means that the hair has a hard time absorbing products, and may feel dry, brittle, and prone to breakage. Low porosity hair can be caused by genetics, but it can also be a result of chemical treatments like coloring or relaxing, which can cause damage to the hair cuticle.
To determine if you have low porosity hair, you can do a simple test. Take a strand of hair and place it in a glass of water. If the hair floats on top of the water or takes a long time to sink, it is likely that you have low porosity hair. This is because the tightly closed cuticle layer prevents water from being absorbed into the hair shaft.
If you have low porosity hair, it's important to use products and methods that can help your hair retain moisture and stay hydrated. This can include using lightweight products, avoiding heavy oils and butters that can weigh down the hair, and using techniques like pre-pooing and deep conditioning to help the hair absorb moisture.