DO NOT USE SOAP TO WASH YOUR HAIR. Anyone who says otherwise is grossly, you hear me?, GROSSLY misinformed. I say this with love.
Let's first make a distinction between soap shampoo bars and soap-free shampoo bars.
Soap Shampoo Bars: Are the result of exothermic (releases heat) chemical reactions between fats/oils, water, and salt. The final pH of soap ranges from 9-10.5. Per our previous blog post on pH and skincare, we know that a pH greater than 7 is alkaline, a pH less than 7 is acidic, and a pH of 7 is neutral.
Soap-Free Shampoo Bars (or syndet bars): Are cleansing bars made with surfactants (cleaning agents), fatty alcohols (typically the long chain alcohols that soften hair), butter/oils, and more. They are not soap and they do not depend on a chemical reaction to form. As such, it is easier to adjust the formulation to achieve desired outcomes, including pH.
Healthy hair has a pH of ~3.67 (acidic). This acidity supports our hairs ability to keep our cuticles laying flat, shiny, smooth, and frizz free. Alkaline pH can disrupt this as it can increase the negative electric charges of the hair. Alkaline pH raises the hair cuticles but it doesn't close them. This results in frizz which is an indication that the hair has been weakened. Many people with frizzy hair will also notice less shine and hair that isn't visually or physically smooth.
Here's why BTB doesn't recommend using bar soaps on your hair:
- Harsh: Their higher pH of 9.0-10.5 is harsh on the hair and cannot be adjusted due to the nature of its chemical reaction. We do not recommend using handmade soaps to wash hair not even if there are apple cider vinegar claims made.
- Soap scum: The salts in soap react with the dissolved minerals in water (calcium, magnesium, copper, etc.) resulting in soap scum that is deposited on to the hair. As you may know, soap scum is insoluble in water. Long term mineral buildup will leave our hair with a dull appearance, dry texture, and/or "crunchy" feel. It may seem like products don't work anymore or like our hair is difficult to style. Pay close attention to your water. Hard water has more dissolved minerals than soft water.
If you're using soaps on your hair, we recommend switching to Bath Thyme Bakery's syndet bars to get your hair back on track.
Here's why BTB recommends using soap-free bar soaps for cleansing your hair:
- pH balanced: If formulated correctly, soap-free (syndet) shampoo bars can create low pH lather on your hair. There is no standard for pH in shampoos, however, we recommend shampoos that range from a pH 4 - 5.5 for adults. This pH range helps reduce frizz and dullness.
- No Soap Scum: There is no reaction between soap-free bars and the dissolved minerals in your water that will cause soap scum or mineral build up.
- Gentle: Depending on the formulations, these bars can be gentle on the hair
Rest assured that the quality of our products are based on these aforementioned standards. On that note, we are excited to introduce our newest line of Bath Thyme Bakery products:
- Sulfate Free Shampoo Bar (pH~5): These bars are gentle enough for every day use and are suitable for all hair types.
- Clarifying Shampoo Bar (pH~5): These bars have a gentle coconut derived sulfate surfactant and a biodegradable chelating agent that removes minerals that are bonded to your hair.
The more you know huh? If you're interested in purchasing a shampoo bar and are not sure if it's soap-free, ask so there's no guesswork on your end!