Porosity and Hydration

How porosity affects moisture in natural hair.

I am often asked, “why is my hair dry?” Or, “what should I do to moisturize my hair?” The reason it is almost impossible to answer those questions directly is because hydration varies per person and hair type. In almost every case, porosity plays the most significant role in hydration for naturals.


Scientifically, porosity is the measure of empty spaces in a material. When referring to hair, it is how your hair absorbs liquid and oils and holds moisture. This is determined by the flexibility of your cuticle layer (the outermost layer of each strand of hair). Like other hair characteristics, porosity is genetic. The only way it is altered is from over-exposure to harsh elements like extreme amounts of sun, or over-processing/damage with chemicals such as dye or relaxers/texturizers. If you recall your relaxed days, when you went to the salon, your stylist was probably using the same products on everyone. Relaxers leveled us all out! We all had very similar porosity levels as the relaxer altered the cuticle making hair more porous, but being natural changes the moisture game significantly.

When a liquid substance comes in contact with your hair, the cuticle opens allowing it to pass through. How porous your hair is determines how much of that substance will go into the hair shaft and how quickly it penetrates. To understand how your hair absorbs, the first thing you need to do is conduct a porosity test (adopted from naturallycurly.com):

  1. Fill a medium-sized cup or bowl with room temperature water.
  2. Take a couple strands of hair from different areas of your head, one from the crown and one from the back.
  3. Lay the strands on the water in the bowl and set a timer for two minutes…
  4. Watch the strands during this time…if they quickly sink to the bottom, you have high porosity. If they do not sink at all, you have low porosity. If the strands begin to sink, but still float or wiggle around, you have medium porosity.

What does all this mean?

Curly girls with low porosity often feel their hair is dry to the touch. The reason is because the cuticle is tightly closed, causing the hair repel moisture, making it hard for products and chemicals to penetrate. This is why hair dye results vary so greatly, as it is hard to predict how fast the color will process. Build-up on the hair can also be an issue as products are not able to pass through very easily.

The best way to combat this is by installing as much moisture as possible when your hair is wet. Once your hair is dry, the cuticle is closed and is not likely to absorb additional product. That’s why piling on extra butters and creams in the days after washing seem to be very short-term fixes. Deep conditioning with hydrating oils and ingredients is what will give you lasting moisture. Some of the best ones to add to your conditioner are coconut oil, argan oil,  and jojoba oil.

In addition to products, hydrating through your diet is extremely important. For every level of porosity, drinking lots of water and eating water-filled foods like cucumbers, watermelon, tomatoes and others will keep your body hydrated, which makes for healthy, hydrated new hair growth.

When it comes to products, you want to try and avoid alcohol, sulfates (especially when listed in the beginning of the ingredients) and extreme amounts of protein. While protein is necessary, you don’t want to overdo it because protein is a building block, not a moisturizer. It makes hair sturdy, not hydrated. If you choose to incorporate protein treatments, try only using them every 4-6 weeks, and choose one that’s infused with hydrating ingredients. Ultimately, the best way to get protein is through your diet with lean meats, eggs and other protein-rich foods.

If you are in between washes, and feel your hair is dry to the touch, you can install some moisture by mixing oil with a little room temperature water and spraying it on your hair when re-twisting or installing bantu knots. The water will help open the cuticle so the oil can pass through.


If you have medium porosity (which is were I fall), you probably feel that your hair is almost always moisturized and requires only small amounts of oil to be added after styling. This is because the cuticle is loose and accepts moisture fairly easily. Deep conditioning with every wash and rotating in hot oil treatments with protein treatments every 4-6 weeks is usually enough to maintain moisture-protein balance.

With products, because almost anything can easily penetrate and absorb into the hair, you want to avoid heavier oils like coconut or EVO when styling. While these are great for treatments, they can turn into a greasy mess on the back-end of a style. Also, most custards will prove to be too heavy and make the hair limp and hard. I prefer puddings and moisturizing gels for styles that need extra hold, and jojoba or argan oil when I feel I need a bit of added moisture.


For high porosity hair, you probably find your hair gets frizzy very easily because your cuticle is almost always open. Virtually every bit of moisture in the air is able to pass through. If this level of porosity is inherited, you can try regular protein treatments and reconstructive conditioners (like Design Essentials or Scruples) as a way to block some of the moisture coming through the cuticle. If your hair has high porosity due to chemical damage (especially high level bleaching), you need to be extra careful with manipulation, as your hair is far more susceptible to breakage. You also need to consider cutting away the damaged hair over time as the possibility of being able to repair it is low.

While leave-in conditioners are important for all levels of porosity, it is extremely important for high levels as you may find it difficult to retain moisture without frizzing after styling. A leave-in with essential oils is going to help the hair hold on to more moisture in the coming days. Also, leave-ins that eliminate frizz and define curls will work to shape hair and seal the cuticle. When styling, you may find it helpful to use products classified as anti-humectants that repel water. In most cases, these are silicone-based products. They keep external moisture out, which ultimately reduces frizz.


Notice how each porosity level has a lot in common with the others. Everyone’s hair needs moisture through deep conditioning and treatments as well as through proper diet. We all have to work to install and retain moisture, but may have different methods of doing so. It’s something you figure out with trial and error! You may also find that you fall somewhere in between where your hair needs a mix of suggested methods across porosity levels.

If your hair feels dry almost all of the time, no matter what you do, first evaluate your water consumption, products used and your routine consistency. After that, consider any medications or supplements your are taking as those may cause changes in your hair and skin. Also, think about any damage you may be causing and find ways to combat it with improved care methods.

9 Comments to Porosity and Hydration

  1. Mo
    This is the first blog/article I have read that clearly explains porosity. I love you videos on YouTube and read you blog. You arr a great motivator to try new things and you help peole learn about and love there hair. Great job.

  2. Thank you!! The best explanation of porosity I have read to date!!

  3. Do you suggest cool water rinses for us Curlies with low porosity hair?

  4. Shanita West // March 31, 2014 at 10:54 pm //

    Hi mo,
    I to have subscribed to your YouTube channel and I very much enjoy it.
    Here’s my dilemma I cornflakes dandruff. I know right, Ewwww! I can wash it and the next day its a shy around my edges when I scratch it flakes up. Sometimes my scalp itch so bad I can’t stop scratch. Yes, I been to the dermatologist and received a dandruff shampoo and a foam to stop the itching and dandruff. It didn’t work long term. Any suggestions to what I need to do?
    I am natural with color on the ends I visit my stylist but I want to pick someone else brain.
    P.S. my hair stays dry. HELP :’ (

  5. Interesting article. Nice read. Keep it up. 🙂

  6. What kind of hair products do I need to use on high porosity hair

  7. Hi Mo!
    I have fine..but thick hair. I seal and moisturize my hair ( l.o.c) but when I take down my hair from twist outs or braid outs from the previous night for when I go to bed…it’s oily. I’m wondering if it’s because the strands is to stubborn to open up or if I use too much product ( I use the amount that is suited per section)?

  8. Irene (from Australia) // January 22, 2016 at 6:26 pm //

    WoW! Mo *really does* know hair! Thank you for your time and effort for sharing what you know, Mo! Much appreciated : )

  9. Hi..I have a question I have baby hair it’s also thin what to use on my hair

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