What to Know About Low Porosity Hair

Medically Reviewed by Debra Jaliman, MD on February 27, 2024
3 min read

‌Low porosity hair is human hair that doesn't readily absorb water and treatments. Your hair may be low porosity if it takes a long time to wet and dry. If you use hair care products, they tend to stay on the surface of your hair rather than being absorbed. This makes hair care treatments less effective. 

Managing low porosity hair comes with unique challenges and it’s important to understand how to care for it properly. 

‌Hair porosity describes the ability of the hair shaft to take in and retain water and other cosmetic products. A human hair shaft is typically made up of three layers — cuticle, cortex, and medulla. The cuticle is the outermost layer. It’s made of plates that overlap each other in a structure very much like roof shingles. The cuticles of low porosity hair are tightly packed together and lie flat, leaving no gaps for moisture to enter. This means that moisture and treatments cannot penetrate the hair. 

Hair porosity is often due to genetics or specific hair grooming procedures. Low porosity hair is more common in people who have straight hair as compared with those with naturally coiled or curly hair.‌

Low porosity hair takes significantly more time to wash and dry than normal or high porosity hair. This is because it repels water stopping it from penetrating the hair strand. When low porosity hair finally gets wet, it takes a long time to dry.

Here are simple tests you can use to determine if you have low porosity hair:

Float test: Pluck a random strand of your hair and place it on top of room temperature water in a bowl. If it rapidly sinks to the bottom, then it's porous. However, if your hair floats for some time, then it's likely to have low porosity.

Spray test: Spray some water on your hair and observe it. Low porosity hair won’t easily absorb the water and will still have visible beads of water on the strand. 

Knowing your hair's porosity is key to selecting the right products and creating a hair care regimen that keeps it healthy. 

‌Low porosity hair repels moisture due to its inherent structure, making it tough to manage and style. Here are some practicable tips to help you tame your low porosity hair and make it moisturized, soft, and flexible: 

Clarify. Clarifying hair involves using a deep cleaning shampoo to remove the build-up of old products on your hair and scalp. Treatments and oils barely penetrate low porosity hair, so they are more likely to remain on the hair and the scalp. These build-ups block hair follicles and adversely affect the health of your hair. 

Moisturize. Your hair needs moisture to make it soft, supple, and resilient. The moisture that is naturally stored within your hair strand may not be enough to keep it flexible. That is why you need to regularly moisturize your hair with leave-in conditioner and other moisturizing products. 

Use light oils. Light oils are more absorbent and thus better suited for low porosity hair. They don’t burden your hair and can penetrate deep into the hair shaft. 

Deep condition with heat. Apply a conditioning product and use a steamer, thermal cap, or hooded dryer to heat up your hair. Heat opens up the tightly woven cuticle and allows the conditioner to push moisture into your hair shaft. Trap the moisture by rinsing off with cold water, which closes the cuticle.

Use humectants. Humectants — materials that love water — are great for low porosity hair. These include pectin, honey, glycerin, and aloe vera.

Humectants draw moisture from their environment and retain it, keeping their surroundings moist. This helps prevent low porosity hair from drying out. 

Low porosity hair doesn't have to be a problem. It’s easy to care for once you learn how. You just need to test out the methods listed above and create a personalized approach that works for your hair.