What Is Porosity?
Porosity is a measure of how well your hair absorbs and retains moisture, determined by the condition of the cuticle layer.
Understanding Porosity
Hair porosity refers to the structure of your hair's cuticle layer and how tightly those cuticle cells lay. This determines how easily moisture and products can enter and exit the hair shaft. There are three porosity levels: low (tightly closed cuticles), medium (slightly raised cuticles), and high (lifted or damaged cuticles). Genetics primarily determine your porosity, but chemical treatments, heat damage, and environmental exposure can alter it over time.
Why It Matters
Understanding your porosity is the single most important factor in choosing the right hair products. Low-porosity hair needs lightweight, water-based products and heat to open cuticles. High-porosity hair needs heavier creams and oils to seal in moisture. Using the wrong products for your porosity leads to limp, greasy, or perpetually dry hair.
How To Apply This
- 1Take the float test: drop a clean strand of hair in water and wait 2-4 minutes. Floating means low porosity, sinking means high.
- 2Try the slide test: slide your fingers up a strand from tip to root. Bumpy texture indicates higher porosity.
- 3Observe drying time: low porosity takes hours to air dry, high porosity dries very quickly.
- 4Use the spray test: spritz clean hair with water. If it beads up, you have low porosity. If absorbed instantly, high porosity.
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Related Terms
Hygral Fatigue
Damage caused by repeated swelling and contracting of the hair shaft from excessive water absorption and drying cycles.
Moisture-Protein Balance
The equilibrium between moisture and protein in hair that keeps it flexible yet strong, preventing both mushy and brittle textures.
Deep Conditioning
An intensive moisturizing treatment left on hair for an extended period to penetrate and repair the hair shaft.
LOC Method
A layering technique that applies Liquid, Oil, then Cream to maximize moisture retention in textured hair.
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