I haven’t used commercial or homemade deodorant in years. I don’t even know how many years. Let me see if there’s a hint here in a previous post . . . Ah. Two years, it would appear. I do use something to deodorize, but it’s just a swipe of pure baking soda. And this single-ingredient, ludicrously cheap stuff keeps me 100% smell free. (I buy it in bulk at WinCo for something like $0.50/Lb. And yes, I do still sweat – this is a deodorant, not an antiperspirant.)
So for two years I have used nothing but baking soda under my arms without incident. I used it directly after shaving and I used it during my on-again, off-again no-shave periods (read: winter). And only now have I begun to experience a problem. The problem is redness and the appearance of a rash. I don’t feel itchy or uncomfortable but I have stopped using the stuff until the redness goes away. Am I butthurt? No! Actually, I’m surprised this didn’t happen a long time ago. It may not look it (or smell it) but baking soda is caustic stuff! The pH of baking soda is 8.3 and the pH of skin is 7. It doesn’t sound like a dramatic difference but remember that the pH scale, like the Richter scale, is logarithmic, meaning that a pH of 8 is ten times more alkaline than a pH of 7. (Also of note: water generally has a pH of 7, also. Both human skin and fresh water are considered to be more or less pH neutral.) I made Matt a stick of DIY roll-on that many a person has raved about but the baking soda darkened his skin after a few weeks and he went back to Tom’s of Maine.
I’m going to derail myself here to make an important point: I do not use baking soda deodorizer because I am afraid of aluminum in commercial deodorant. Just as there is no connection between aluminum cookware and Alzheimer’s, there is also no link between aluminum in deodorant and breast cancer. I use baking soda because A) I dislike the way every cream-based deodorant in the universe leaves a disgusting rime on the armpits of my shirts, and B) I’m cheeeeeeeeeeeeeeeeap.
So, what’s the solution?* The crystal? Well, I’ve heard pretty conflicting reports about their efficacy, I could not readily find data on the pH of Potassium alum (the chemical name for the crystal), and I didn’t want to have to spend money on one. (Dr. Cox voice: Chuh-heeep!)
So I figured that if my scalp and hair are happy with the one-two punch of baking soda followed by (and essentially cancelled out by) vinegar, then why wouldn’t my pits? Crunchy Betty to the rescue (again): Mix equal parts vinegar and water, dab on, and, when dry, follow with a dusting of baking soda, as usual.
*Unintentional chemistry pun!
 Ophardt, Charles E. “pH Scale” Elmhurst College Virtual Chembook. (
http://www.elmhurst.edu/~chm/vchembook/184ph.html) Copyright 2003, accessed 03/18/15. [07/27/15 NOTE: Chembook no longer available online]
 “Why Your DIY Baking Soda Deodorant is Causing a Skin Reaction” http://www.lisaliseblog.com/2012/10/why-your-diy-baking-soda-deodorant-is.html. Accessed 03/18/15.
 “New News and pH Balancing Your Old Homemade Deodorant Problems” (http://www.crunchybetty.com/new-news-and-ph-balancing-your-old-homemade-deodorant-problems) Posted 06/22/13. Accessed 03/18/15.