Baking soda deodorant can sting because baking soda is alkaline, about pH 8.3 in water, and skin's surface runs acidic. The extra smell after you quit antiperspirant comes from armpit bacteria bouncing back, and I found no evidence that a clay detox pulls toxins out through your armpit. Crystal sticks carry aluminum too.
We make no deodorant and no antiperspirant, so there's nothing of ours riding on which one you keep. If yours works and your skin's calm, keep it. Below is what the studies found, and I'll flag where the research runs thin.
Why does baking soda deodorant sting?
Baking soda is sodium bicarbonate, and a fresh solution of it reads pH 8.3, according to PubChem. Skin sits on the other side of neutral. A 2025 review in the Journal of Investigative Dermatology by Brooks and colleagues puts the skin's surface between pH 4.1 and 5.8, and below 5 when nothing's on it. Folds like the armpit tend to run higher than the rest, they note.
Alkaline products push that number up. Natural soaps lift the surface to about pH 7.5, the same review says, and it takes several hours to drift back. That matters for the barrier. An alkaline surface can speed up enzymes called serine proteases, which get in the way of the layered lipids the skin barrier is built from. Soap gets rinsed off. A deodorant's left on all day, and it goes back on tomorrow.
On skin that reacts, the likely result is what dermatologists call an irritant reaction, which differs from an allergy. A 2024 review of armpit contact dermatitis in Cutis by Musicante and colleagues says irritant reactions come on faster than allergic ones and tend to burn and sting more than itch. Not every armpit reacts, and I couldn't find a study that counts how many baking soda users do.
If a stick stung you, read the ingredient list for sodium bicarbonate and pick one without it. Baking soda's in those sticks for a reason: a 2023 review by Teerasumran and colleagues lists it among deodorant ingredients with antimicrobial activity. The same review describes zinc ricinoleate as odor-binding, a different route to the same job.
Why do you smell worse after quitting antiperspirant?
Sweat leaves the gland with no smell, the Teerasumran review notes, and bacteria on the skin digest parts of it into odor compounds. That's where antiperspirants step in. Their aluminum salts form plugs that block the sweat glands, which leaves the bacteria less to work with.
A 2016 PeerJ study looked at quitting directly. Urban and colleagues had 17 volunteers drop all underarm products for five days, then wear antiperspirant for two. It's a small study, and a useful one. Once antiperspirant users stopped, the bacteria the team could culture climbed toward the counts on people who use nothing. Antiperspirant then cut counts by an order of magnitude.
The species makeup tracked long-term habits, and it didn't shift measurably from day to day. People who habitually used no product carried far more Corynebacterium than antiperspirant users, and the authors tie that group to the armpit's dominant odors. Recent quitters were dominated by Staphylococcaceae instead. They write that the change lasts multiple days after stopping, and they call for longer studies.
No study I found has timed a full switch. Any number of weeks you've been promised is a guess until someone runs that longer study. The extra smell has a plain cause. More bacteria grow back, with more sweat to work on once the plugs are gone. That's the skin microbiome at work. Nothing in the data points to toxins leaving your body through the armpit.
What does an armpit detox do?
The armpit detox is a paste of bentonite clay and apple cider vinegar that sits on the skin before it's rinsed off. The pitch is that it draws toxins out through armpit skin and shortens the switch. Clay's good at grabbing things. The FDA describes bentonite as principally a colloidal hydrated aluminum silicate whose fine particles give it pronounced adsorptive capability. That grip works where the clay touches, on surface oil and sweat.
The body's waste work happens elsewhere. MedlinePlus counts removing poisons among the jobs of the liver, the largest organ inside your body. A 2019 physiology review by Baker found that sweating's role in clearing waste and toxicants seems minor next to the kidneys and gut, since sweat glands don't adapt to excrete more. I couldn't find a study that tested an armpit mask for pulling anything out of the body. So the detox is a mask with a story. If you like how your armpit feels after one, that's your call, and the clay still does its surface work.
Is a crystal deodorant aluminum-free?
No: crystal sticks are alum, and the Cutis review describes alum deodorants as aluminum bound to potassium or ammonium, in crystal or powder form. They're considered a natural alternative, and potassium alum is still an aluminum salt. The same review notes reported reactions to alum crystals, from a typical itchy red rash to a granulomatous kind with red-brown bumps.
The clay in a detox mask counts too. Bentonite is principally an aluminum silicate, in the FDA's words, which is worth knowing if aluminum's the reason you switched. Read the label for alum. For patients allergic to aluminum, the review notes, clinicians may suggest aluminum-free deodorants or homemade recipes built on powders like arrowroot and cornstarch. If your crystal works and your skin's calm, nothing here says you've got to stop.
Where does a tallow balm fit?
A tallow balm isn't a deodorant, and it does nothing about sweat or the bacteria behind the smell. It's a fat that holds moisture in the skin. If a rash hasn't settled once the stick's gone, a dermatologist leads. I make the balm I'm about to recommend. It's cosmetic care, not a treatment, and your provider's plan comes first.
Once the skin's calm and intact again, the jar I'd use is Bare Silk ($34, as of October 5, 2026) in the Unscented original, with no fragrance and no essential oils. A thin layer at night relieves the dry, tight feel that can follow. Keep it off raw or broken skin.
If you'd rather not read five product pages, Find my balm asks two minutes of questions and hands you the jar.
Questions we hear
Why does baking soda deodorant burn?
Baking soda is alkaline, about pH 8.3 in a fresh solution, while skin's surface sits below pH 5 when nothing's on it, a 2025 review found. Alkaline conditions can upset the barrier's lipid layers. Irritant reactions in the armpit tend to come on fast and burn or sting more than itch. If a stick does that, stop using it. Look for one without sodium bicarbonate, baking soda's chemical name, on the ingredient list.
Does an armpit detox work?
It works as a clay mask, and only on the skin's surface. Bentonite clay's fine particles grab what they touch, so it can take up surface oil and sweat. Your liver helps remove poisons. A 2019 physiology review found sweat's part in clearing waste and toxicants seems minor next to the kidneys and gut. I couldn't find a study showing a mask pulls toxins out through the armpit.
How long does the deodorant switching period last?
No study I found has timed the switch off antiperspirant from start to finish. In a 2016 PeerJ study by Urban and colleagues, armpit bacteria counts in antiperspirant users rose within days of stopping and approached the counts on people who use nothing. That study ran eight days, and its authors called for longer ones. Until there's a longer study, any promised number of weeks is a guess, so trust your own nose.
Is crystal deodorant aluminum-free?
No: crystal deodorants are alum, which a 2024 dermatology review in Cutis describes as aluminum bound to potassium or ammonium. They're considered a natural alternative, and they're still an aluminum salt. The same review notes reported skin reactions to alum crystals, including a granulomatous kind with red-brown bumps. If aluminum's what you're avoiding, skip the crystal.
Go deeper
The beef tallow for skin guide covers what tallow does on skin and what it doesn't. If your armpit reacts to scent as well, fragrance-free vs unscented sorts out the label words, and tallow for sensitive skin covers a gentle start. The cancer question that usually starts the switch is in aluminum antiperspirants and cancer, and why we don't make a deodorant is the honest answer to the jar people ask us for.
Sources
- Brooks SG and colleagues (2025). The skin acid mantle: an update on skin pH. Journal of Investigative Dermatology 145(3):509 to 521.
- MedlinePlus (2026). Liver diseases, page last updated July 27, 2026. MedlinePlus.
- US National Library of Medicine (2026). Sodium bicarbonate, pH entry from the Hazardous Substances Data Bank, read October 5, 2026. PubChem.
- US Food and Drug Administration (2026). Code of Federal Regulations, title 21, section 184.1155: bentonite, read October 5, 2026. eCFR.
- Musicante MJ and colleagues (2024). Axillary contact dermatitis: an update on potential allergens and management. Cutis 113(1):35 to 42.
- Teerasumran P and colleagues (2023). Deodorants and antiperspirants: new trends in their active agents and testing methods. International Journal of Cosmetic Science 45(4):426 to 443.
- Baker LB (2019). Physiology of sweat gland function: the roles of sweating and sweat composition in human health. Temperature 6(3):211 to 259.
- Urban J and colleagues (2016). The effect of habitual and experimental antiperspirant and deodorant product use on the armpit microbiome. PeerJ 4:e1605.
Brian is the founder of Craft Tallow, a small-batch tallow skincare line shipped from Cottonwood Heights, Utah, built on 100% grass-fed suet. Questions? Reply to any email from us; it lands with him.