If I had a penny for every time I've heard somehow say: “I’d love to use an all-natural deodorant, but I tried one with baking soda and experienced irritation.”
For some, baking soda can cause redness, irritation, burning, and occasionally even swelling. Some people think this irritation is an allergic reaction or “detoxing”. Spoiler: it’s not. Yes, your pits can go through a detox period, but this shouldn't cause redness or irritation. The irritation is also (usually) not a symptom of an allergic reaction. Baking soda is in a lot of foods and products, so unless you get an allergic reaction from cookies, it's most likely not what is causing it.
Baking soda is a critical ingredient in natural deodorants because of its antibacterial properties which help control bacteria growth and neutralize odor.
So what's the cause of the redness and irritation some people experience? It’s science, my friends. Or more specifically, pH balance.
Come take a journey with me to elementary school. Remember that epic science experiment where you used vinegar and baking soda to make a volcano? Your teacher probably took the time to explain why baking soda + vinegar = volcano, but for those who have misplaced their notes: that reaction happens because baking soda has a basic (high) pH and vinegar has an acidic (low) pH. The combination of high and low pH causes a reaction.
Essentially, this is what happens to some people when they apply deodorant with high levels of baking soda. Our underarms are acidic, and baking soda is basic, so a reaction can occur and cause redness and irritation!
Why do some people have a reaction and others don’t? It’s entirely dependent on your temple’s pH level. Your pH can be affected by age, gender, diet, hormones, among other things. We spoke with a dermatologist who estimated that only ~5-10% of women experience skin reactions from baking soda, and some only experience it during their menstrual cycles.
But we all prefer 0% chance of angry pits, right? That’s why Curie has worked tirelessly, relying on a tremendous amount of real-world testing and feedback from our amazing customers to develop a deodorant formula that is gentle on those sensitive to baking soda, without sacrificing efficacy. We offer both a stick deodorant, formulated with low baking soda, and for those with ultra-sensitive skin, or that cannot tolerate baking soda, we also have a deodorant spray that's baking soda free. And if you just cannot choose, check out our starter pack, which comes with both!