Hair Issues || High Porosity (and Low Porosity)

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Porosity.  What is it?  It is a measure of how easily water and other substances can enter and exit the hair strand.  Depending on the condition of the hair's cuticle layers, the porosity can rank from low (i.e., the result of flat, tightly bound cuticles) to high (i.e., the result of gaps or lifted cuticles).  Highly porous hair, in particular, is more susceptible to moisture loss and breakage.  If your hair is highly porous, read the following article on how to combat the issue:

ADDRESSING HIGH POROSITY

For low porosity or more on porosity in general:
POROSITY EXPLAINED