We frequently get asked about this ingredient in our dry shampoo. "Will this ingredient irritate my scalp?" "But what about pH?" "Why would you put baking soda in dry shampoo?" "Is your baking soda aluminum free?"
First, let's talk about what baking soda (or, sodium bicarbonate) is and where it comes from.
Sodium bicarbonate is a crystalline chemical compound generally recognized around the household as cheap and useful. Like any industrial chemical, there's an array of ways that baking soda can be manufactured.
The first and most sustainable way is through natural mining. In this process, sodium bicarbonate is drawn directly from the ground in its natural state. Large pipes pump water into and back up out of the ground. The sodium bicarbonate is then extracted from this "brine" and dried to create the powdered stuff you find on the store shelf.
Brands like Bob's Red Mill and Natural Soda are manufactured this way. Some of the world's largest sodium bicarbonate mines are right here in the United States (Colorado, Wyoming, and California to be exact) so, buying natural baking soda is like buying local in a way.
The second and less desirable option is through the Solvay process. This method chemically synthesizes limestone, salt, and ammonia to achieve the desired end product of sodium bicarbonate. It is an environmentally taxing process with a slew of hazards including toxic waste production and high fossil fuel use. Brands such as Arm & Hammer baking soda utilize this method.
Is all Baking Soda Aluminum Free?
As mentioned before, naturally mined baking soda comes from the ground in its natural state along with a conglomerate of the Earth's elements. It is then minimally processed to refine it into a percentage of sodium bicarbonate. Is there a trace amount of aluminum in there? Maybe. Is any aluminum added during the manufacturing process? No. This is true for both processes--natural and synthesized.
Is Baking Soda Bad for Your Hair?
You may have heard that baking soda has a pH of 9 and your scalp has a pH of 4-5. These are both true (kind of), but it's time to do some debunking.
By definition, pH is defined as the decimal logarithm of the reciprocal of the hydrogen ion activity, aH+, in a solution. In plain English, pH is a measure of how base or acidic an aqueous or liquid solution is.
Baking soda is a solid. So, in order to measure the pH of baking soda, you would have to first dissolve it in water. If we were just dumping baking soda on our heads, the pH of baking soda alone would be the only relevant information.
However, our dry shampoo is a mixture of baking soda with other natural ingredients. Since our product does come in contact with water on your scalp during a shower, the pH of our product is relevant and has been thoroughly tested. The combined pH of our dry shampoo is in symbiosis with the average scalp pH of 4-5.
Learn more about our dry shampoo and how we are making good hair healthy again.