The Efficacy of Shampoo Bars

Hair Liberty’s Nicole Harmon, our Resident Curl Chemist, is answering your most urgent hair questions. Got one for her? Email me at nikki@curlynikki.com using “Hair Liberty” in the subject line and she may answer your question right here on the blog.

Q: I want to try shampoo bars, but I’ve seen mixed reviews. Will they work for my hair?

A: To answer this question, we need to examine the labels of two popular shampoo bars:

Oyin Handmade Grand Poo Bar
Ingredients- purified water, glycerin, sodium stearate and sodium oleate, sorbitol, stearic acid, lauric acid, African black soap, cocoa butter, cetyl alcohol, coconut oil, lavender, tea tree and citrus essential oils

Karen’s Body Beautiful Bodacious Beauty Bar (Shampoo Bar), Juicy
Ingredients- purified water, saponified olive, coconut and safflower oils, jojoba oil, shikakai & amla herbs, apple cider vinegar and panthenol

These shampoo bars are made with slightly different recipes, but they are both made of soap. Soap is made by mixing water, fat from a vegetable oil or butter, and sodium hydroxide (lye).
For all intents and purposes, the “sodium stearate and sodium oleate” in the Oyin Poo Bar are the same as the “saponified olive, coconut and safflower oils” in the KBB Shampoo Bar. Oyin used the scientific names for soap in their ingredients list, while Karen’s Body Beautiful used more laymen terms. In the “sodium oleate” listed in the Grand Poo bar, the “sodium” comes from sodium hydroxide and the “oleate” means the fat used was from olive oil.
Soap has been made using sodium hydroxide or potassium hydroxide for centuries, but it’s always had two major problems:

1) It’s impossible to make pH balanced soap. As we know, sodium hydroxide has a high pH and the resulting soap usually has a pH around 10. An expert soap maker can make a soap bar as low as pH 8. Attempting to lower the pH below 8 will make the soap resemble mud (not a solid bar anymore). Some hair types aren’t affected by high pH, but curly-kinky hair is pH sensitive because of its naturally raised cuticles. It’s always best to use shampoo with a pH between 4.5 and 6.5.

2) Soap causes soap scum in hard water. If you use a shampoo bar in tap water that contains a lot of calcium, the calcium will attach to the saponified olive oil/sodium oleate and form scum that settles on your hair (and leaves stains in the tub). Those mineral deposits will make your hair more prone to tangles and knots. Hard tap water is common in Southern California, the Mid West, and Texas. If you have hard water, your hair and skin will feel and look better if you avoid soap.

*The Karen’s Body Beautiful Beauty Bar contains Apple Cider Vinegar, but it’s not in a high enough amount to counteract hard water.

There’s a learning curve to going natural and it takes time to learn what works best for your hair. If you are just starting out on your healthy hair journey, I recommend avoiding shampoo bars. You will find a good regimen for your hair more quickly if you use products that are scientifically proven to work well for your hair type.

Instead of paying around $10 for a shampoo bar, it would be better to spend the same amount to get a large bottle of Nature’s Gate or Avalon Organics shampoo. Those products are made with gentle cleansers, they’re pH balanced and they include ingredients to counteract hard water. If you’re still curious about shampoo bars after you find your holy grail regimen, feel free to experiment. You’ll get a better sense of whether you like them or not after you’ve had some experience with a well-formulated shampoo.

If you choose to wash your hair with a shampoo bar or any other soap, always rinse the soap scum off of your hair at the end of your shower using 1 cup ACV mixed with 1 cup warm distilled water.