The pH of hair, skin and products (and why it matters!)

Good morning Soapsmith Nation! I have been thinking a lot about pH lately (I think about it all the time really). At a recent market I was chatting with a customer and he asked if I made any bar soaps that were anti-bacterial. "Of course I do, actually all handmade bar soap is anti-bacterial," I explained to him, "but I don't need to add anything to make them that way." He looked puzzled until I explained that the natural pH of handmade soap is typically around 10 and in that type of alkaline environment bacteria, mold, yeast, fungus etc. do not survive. He seemed grateful for the simple explanation and told me that of all the soap vendors there that night (I was 1 of 4) not one of them had been able to articulate that information to him. I felt flattered and super nerdy (which I wear like a badge of honor) to have been able to help him out.

Let's back up a second. What is pH and why do I think about it non-stop? Simply put pH, or potential hydrogen, is a scale of acidity from 0 to 14. It tells how acidic or alkaline a substance is. More acidic solutions have lower pH of between 1-6.9. More alkaline (aka basic) solutions have higher pH at 7.1-14. Substances that aren't acidic or alkaline (that is, neutral solutions) usually have a pH of 7 (pure water has this pH). Why do I think about it non-stop? I take pH into consideration when creating products and need to decide if it is appropriate for the skin which it will be used on. Some products have a pH which may not match the pH of skin exactly so then I must further ponder if it will throw the pH too far out of balance and if I need to adjust the product to be more compatible, (see....super nerd here, ha). One last note about pH is that between 2 whole numbers are 10 fractions of a number. Example between pH 5 and pH 6 are all the fractions of 5.1, 5.2, 5.3, and so on. So when I say your skins pH is 5.5 that is 5 fractions away from pH 6 instead of a half of a fraction. pH 5 to pH 6 is 10 times the difference from one to the next and pH 4 to pH 6 is 100 times different (10 x 10)! Long story short, the distance between one whole number and the next is much longer than it appears on the surface.

The pH of our skin is 5.5 and the pH of hair is between 4.5-5.5 with virgin hair being even lower at 3.67. As we now know, the pH of handmade soap is around 10. Is this a bad thing? Well let's consider a couple of things first. The layer that we are affecting by washing, scrubbing, exfoliating and later moisturizing with lotion is called the "acid mantle" it can take anywhere from 15 minutes to 14+ hours to repair itself depending on the level of damage incurred. If your skin is feeling tight your acid mantle may have been negatively impacted by something. We want this to be balanced and functioning properly because it keeps bad things like bacteria, yeast and fungi out and good things like fluids in. Some skin is thicker than other skin on the body, this is good to know when deciding what to use on your body. The skin on your face is very thin (0.5mm on your eye lids) to thicker (4mm on the soles of your feet). The different parts of your body can handle different amounts of stressors and reset faster keeping your acid mantle in check. With that being said, I will be the first person to tell you that I no longer use my handmade soap to wash my face. As I have aged I noticed more frequently that my face skin felt tight and that's not how it should feel. When I went to get a facial the esthetician told me that my skin on my face had been stripped of its natural oils and was in need of repair. I knew what that meant, it was time to switch to a pH appropriate gentle facial cleanser. My face skin is clear, bright and no longer tight (although it hurt my heart to have to stop using my own soap to wash my face.) I still use my soap on the rest of my body and don't have issues with dryness or tightness so the thicker skin seems to be able to reset in a reasonable amount of time and to keep the bad things out and good things in for me:).

While the skin can reset itself in due time the hair cannot. I NEVER, NEVER, NEVER, recommend handmade soap be used on hair. Many people claim that it works great and their hair feels good and a simple apple cider vinegar rinse is all their hair needs and that's fantastic for them but what they don't realize is that when they use handmade soap on their hair it causes the hair shaft to swell exponentially and the cuticle to lift. If you have colored hair this is even worse because it will cause your color to fade faster. Even if you do not have colored hair all those little cuticles get tangled together and can cause breakage and a frizzy appearance. Some soapmakers claim they have a special and gentle formula for hair, I am not here to debate or knock another maker but I will say that scientifically there is no way to bring the pH of handmade soap down low enough to be appropriate for hair without destabilizing the formula which in the end makes a puddle of ingredients as opposed to making a bar of soap. Even liquid soap made with KoH is alkaline and inappropriate for hair care.

I have been fascinated by shampoo and conditioner bars lately I love that they help to reduce plastic waste, they are great for travel and last for quite awhile. I have been exploring ingredients which have a more appropriate pH for the skin and hair, bring in the LAB CREATED INGREDIENTS (imagine trumpets here). Look, just because something is "natural" doesn't automatically make it safer than something made in a lab. Snake venom is natural but deadly. Sodium Cocoyl Isethionate is a coconut derived gentle surfactant with a pH of 4.5-6.5. Lab made ingredients are stable and consistent which is a huge benefit to them, also they do not deplete natural resources as some naturally derived ingredients do.

Shampoo Bars by Soapsmiths

Over the past 6 months I have developed a formula for a shampoo bar that is pH appropriate for hair and skin. I have been lovingly calling it "The everything bar" because it can be used on, well, everything! I wash my hair with it and sometimes my body, it's actually fabulous for shaving too! It leaves me feeling silky and my hair is not frizzy or tangled either. I used lab made ingredients and have been checking in with cosmetic chemists that I am familiar with to ensure that my formula is correct and appropriate. My faithful group of testers have had really positive feedback on these bars and one tester even went ahead and bought an additional 2 so she would have them! I am currently working on a conditioner bar, and hope to get it into my testers hands soon so that I can then share it with you all.

So this is the long and short of pH and why it is important. In researching this information for the post I have decided to create a post on the skin where we will dive deeper into the various layers and what they do so stay tuned for more science-y fun.

Until then, stay bubbly my friends
~Your Soapsmith