At-home concoctions can work well as treatments for curly haired naturalistas. But solutions that include baking soda often yield mixed results. Why? The answer includes a digestible amount of hair-related chemistry and biology—info that will, according to Naturallycurly.com, help you anticipate bad natural hair-care experiments before they go awry.

Baking soda is also known as sodium bicarbonate, a chemical that’s been around for hundreds of years. In today’s digital age, devotees of this white, powdery compound abound on the Internet. They claim that scalp-cleansing baking soda also works on hair like a shampoo and softens strands like a conditioner.

But how does African-American hair react to baking soda? A journey back to high school chemistry class wouldn’t reveal how this ingredient affects hair—unless your lab mate dumped a batch on your head—but a quick refresher course on pH balance (meaning the “potential of hydrogen”) can help those on a mission to achieve healthy hair.

Simply put, pH levels range from 0 to 14. These numbers measure the amount of hydrogen ions in a compound. If a substance is acidic, such as lemon juice, it has more hydrogen ions and a low pH, anywhere from 1 to 6. But if a substance is alkaline (or basic), such as baking soda, it has more hydroxide ions and a high pH number—8 to 14. If a substance (for example, distilled water) has a pH measurement of 7, it’s neither acidic nor basic; it’s neutral.

Here’s how all that relates to your hair: Natural tresses usually have a 4.4 to 5.5 pH. That means that untreated hair is slightly acidic. Yes, it may sound bad, but that’s a good thing. For your strands to remain healthy, your hair’s pH has to remain in that range. In other words, balance is key.

Think of it this way. Water from a bath or shower can raise your hair’s pH, effectively throwing your strands off balance. So imagine what can happen to your mane when you sprinkle on baking soda (with a pH of 9) or apply chemical relaxers (with a pH of 14). Yikes!

To better understand what happens to your strands when you add substances that violently shift their pH, imagine a close-up of your hair’s outermost cuticle layer. Any acidic product will close the cuticle layers of your hair, while something basic will open them. When the cuticle layers are raised by an alkaline substance, that means moisture is allowed into your hair. But this also means moisture can escape from your hair just as easily. That might be why many people experience extremely dried-out hair after using mostly baking soda products.

The upshot? Baking soda is not recommended for naturals unless you’re using an acidic substance, such as apple cider vinegar, to close your hair cuticle layers after the baking soda has opened them up.

It might also be helpful to know that temperature can affect the cuticles of your hair: Warm water opens hair cuticles, but very cold water shocks them shut—one reason why many naturalistas choose to splash tresses with frigid water to lock in the moisture while conditioning.
Click here to read about how keeping hair tools clean is important for your mane and scalp.