Tried Every Moisturizing Product Under The Sun And Your Hair Is Still Dry? Read On...

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Do you find that you are moisturizing your hair religiously to no avail? It may not be the products you are using, the issue could instead lie in the porosity level of your hair. The porosity level determines how well your hair is able to absorb and retain moisture within the cortex, and overly porous hair can have a hard time retaining moisture from even the best moisturizing products. Lack of moisture isn't the only drawback to having overly porous hair, hair that is highly porous also absorbs heat faster than hair with low or normal porosity levels which means your hair is more prone to heat damage.

What can cause porosity issues? Improper thermal straightening techniques, excessive heat [from blow dryers, flat irons, curling irons, pressing combs etc], relaxers, and color applications. 

How will I know if I have porosity issues? Hair may appear straw-like and dry even after moisturizing. Hair may also have a tendency to air dry faster than normal. Hair may often feel "rough" to the touch. Hair may also be prone to excessive tangles and matting even though your ends are trimmed. Still not sure? Take the porosity test: Rub your fingers up a few strands of hair from end to root, if it feels rough, or bumpy, chances are you have raised or lifted cuticles which can also indicate issues with porosity [porosity issues stem from damaged cuticle layers]. Hair that has low or normal porosity levels should feel smooth up and down the hair shaft.

I am natural, can I use products geared towards correcting porosity? The answer is YES! If you use pressing combs, flat irons, and/or blow dryers you are susceptible to porosity issues. - Also as some of us age, certain hormonal changes take place that may also affect the density, texture and porosity of your hair.

How to correct issues with porosity?

Roux Porosity Control $12.99-15oz : Porosity Control works by depositing protein that binds to holes and gaps along the cuticle, Porosity Control also corrects the PH balance of the hair. On-going treatments are recommended to help reinforce the cuticle layer for severely damaged hair.
To use: Shampoo hair and lightly towel dry with a microfiber towel, apply about 1/8 cup of Porosity Control, and sit for about 3-5 minutes. Rinse out the porosity control with cold water*, and follow up with a moisturizing conditioner [since porosity has temporarily been corrected, hair is in it's optimal state to receive and retain nutrients/moisture] for another 25-30 minutes [with plastic cap].  
You can find Porosity Control at most if not all Sally's Beauty Supply Stores

*Why rinse in cold water? This closes the cuticles [raised cuticles is a major culprit in regards to frizz], which seals in nutrients from your conditioner, seals in moisture, and also imparts an incredible amount of shine.

Apple Cider Vinegar: Conditioning treatments that cater to the needs of those with overly porous hair [these products will be marketed as conditioner for "color treated hair"] are usually on the acidic side. Since Apple Cider Vinegar is also midly acidic, it is a cheaper alternative to pricey conditioners. Apple Cider vinegar works the same in that it temporarily constricts the cuticles correcting porosity levels.
To use: Take 1/3 cup of Apple Cider Vinegar and add it to 2-3 cups of cool Distilled water, use this mixture as a final rinse [do not rinse out], for shiny, tangle and frizz free hair.

Roux Fermodyl 619 Extra Strength $8.49 for 3 vials: If you press/relax/or color your hair regularly; I suggest you incorporate this into your regimen [once monthly]. Fermodyl helps correct porosity and elasticity issues, and is specially formulated for coarse, and curly hair. Because Fermodyl is formulated with Lactic Acid, it also makes detangling a breeze, which can help cut down on damage from combing!  
To use: Towel dry hair with a microfiber towel or t-shirt. Section your hair into four sections, and apply Fermodyl to each section prior to applying your leave in. I would use one vial for my entire head.
You can find Fermodyl at most if not all Sally's Beauty Supply stores.