We don't make a deodorant, because an underarm's trouble is sweat and the bacteria that live on it. A balm answers dryness. That's a different job, and the chemistry below shows why we've left the underarm alone.
If the skin around your underarm runs dry, the one jar of ours I'd put there is Bare Silk ($34, as of October 5, 2026). I mean the Unscented original, with no essential oils or fragrance in it. Intact skin only. It's never a stand-in for your deodorant, and nothing on this page will ask it to be one.
What makes an underarm smell?
Two kinds of sweat glands matter most here, and the typical underarm smell starts with one of them. Eccrine glands do the cooling. Baker's 2019 review of sweat gland physiology counts about 2 to 4 million of them across the body. Their sweat is mostly water and salt. Apocrine glands sit mainly in the armpit and a few other places, and they don't start secreting until puberty. What they make is thicker, a fat-rich sweat that also carries proteins.
Fresh apocrine sweat doesn't smell. A 2020 review by Natsch and Emter describes it as odorless until skin bacteria reach it. Corynebacteria are the ones that review keeps returning to. Enzymes in these bacteria split odorless molecules in the sweat into pungent acids and sulfur compounds. Odor tracks their numbers. None of that is dryness, the one thing a balm is built for. Our post on the skin microbiome without the hype covers the bacteria that live everywhere else on you.
Antiperspirant vs deodorant: what's the difference?
An antiperspirant is an over-the-counter drug, and the FDA's rule for it is 21 CFR part 350. By that rule's definition, it reduces sweat where you put it. The active has to come from a list of aluminum salts, capped at 25% for aluminum chlorohydrate and 20% for the aluminum zirconium kinds. Zirwas and Moennich, in a 2008 paper on underarm allergy, describe them as blocking the eccrine glands. There's a number behind the bigger claims, too. "All day protection" needs a 20% cut in sweat over 24 hours, and "extra effective" needs 30%. Every label has to warn against use on broken skin and tell you to ask a doctor first if you have kidney disease.
A deodorant is a cosmetic. The FDA counts "acting as a deodorant" among cosmetic uses, and a stick that does both jobs is a cosmetic and a drug at once. Deodorants work two ways, according to Zirwas and Moennich. Antimicrobials thin out the bacteria that make odor, and fragrance covers what's left of the smell. Neither changes how much you sweat. In the FDA's definitions, affecting a body function is one of the marks of a drug.
What do natural deodorant ingredients do?
A natural deodorant is still a deodorant, a cosmetic like any other on the shelf. None of its usual ingredients is on the FDA's antiperspirant list, so none of them can be sold as a sweat reducer under that rule. They work on odor or wetness instead. The evidence behind each one varies a lot.
Baking soda is the classic. It's an alkaline powder, meant to neutralize the acids in underarm odor, and it has a reputation for stinging some underarms. I couldn't find much published research measuring how often that happens. You'll see magnesium hydroxide sold as the gentler alkaline swap, and zinc ricinoleate, a zinc salt made from castor oil, sold as an odor trap. I found little human testing of either in an armpit. Arrowroot is a starch that takes up some surface wetness, and it doesn't reach the gland.
Essential oils carry the scent. Scent is where the allergy question lives, and it's the part of a natural deodorant I'd look at hardest. When Zirwas and Moennich went through a pharmacy chain's database, fragrance turned up in 90% of the deodorants and was the most common allergen they found. They call essential oils known sensitizers. The patient in their case report reacted on patch testing to tea tree oil and lavender, among a long run of plant and fragrance allergens. "Natural" doesn't change how skin reacts. Our Never List keeps synthetic fragrance out of every jar, and a scent comes from a botanical named on the label or there isn't one.
Is deodorant for men any different?
Not in what's in the stick, and that's set by rule. The FDA's list of sweat-cutting actives has no men's column, so a men's antiperspirant draws on the same aluminum salts at the same caps as anyone's.
Where men do differ is in which bacteria tend to win. Callewaert and colleagues sorted the armpit bacteria of 53 people in 2013, and their groups leaned by sex. Of the 17 women, 87% fell in a Staphylococcus-dominated group. Of the 36 men, 39% landed in a Corynebacterium-dominated one, the group the odor research keeps pointing at. Hair adds to it. Natsch and Emter note that the armpit's shape and hair keep it moist, which suits bacteria. If a men's deodorant smells different, that's a fragrance choice, and fragrance is the allergy risk covered in the section before this one.
What about sweating and odor in menopause?
Hot flashes and night sweats, also called vasomotor symptoms, are feelings of warmth that can come with flushing and sweating, The Menopause Society explains. Night sweats are hot flashes that happen in sleep. Each episode usually lasts between 1 and 5 minutes, and they're common, affecting up to 80% of women for an average of 7 to 10 years.
Whether menopause changes underarm odor itself is a question I couldn't find good research on. So I won't guess. What's clear is who manages the sweats, and the answer is a clinician. The Society says hormone therapy is FDA approved as a first-line therapy for hot flashes, and only two nonhormone medicines have FDA approval for them. Its non-drug suggestions include cooling, by adjusting clothing or the room's temperature, and avoiding triggers such as alcohol and caffeine. Nothing in a jar of ours changes a hot flash or a night sweat. It's cosmetic care, not a treatment. Your provider's plan comes first, whatever you put under your arms.
What helps sensitive underarms?
Start with fragrance-free, since fragrance is the most common allergen in deodorants by Zirwas and Moennich's count. Their case shows how stubborn it can be. A man with years of itchy underarm rashes had two standard patch tests come back clean. Expanded testing at a specialist center found his fragrance allergies, and his rash didn't return once he switched to fragrance-free products. Fragrance-free and unscented aren't the same promise. Our post on fragrance-free vs unscented explains what each label word means.
Leave baking soda out while you test, given its reputation, and patch test any new product before it goes under your arm. Here's the American Academy of Dermatology's method. Put the product on a quarter-sized spot on the underside of your arm or the bend of your elbow, twice a day for seven to 10 days. If the spot turns red or swells, wash it off and don't use it again. A rash that keeps coming back after you've switched is a dermatologist's call, and expanded patch testing is how that man found his answer.
That's where a balm stops. It isn't a deodorant, and on an underarm, a fat holds moisture against skin that's already damp. It does nothing about the sweat and isn't made for the bacteria. We'd rather say so than pour one.
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
Does tallow work as a deodorant?
No. Tallow is a fat, and it doesn't plug sweat ducts the way an antiperspirant's aluminum salts do. Underarm odor comes from skin bacteria breaking down sweat. I haven't found a study that tested tallow against that odor, and we don't sell our balms as deodorant. A tallow balm belongs on dry skin. For wetness and odor, we'd point you to an antiperspirant or a deodorant made for the job.
What's the difference between antiperspirant and deodorant?
An antiperspirant is an over-the-counter drug in the US, built to reduce sweat. Under the FDA's rule, its active has to be one of a listed set of aluminum salts, which block the sweat glands. A deodorant is a cosmetic that works on odor instead. It uses antimicrobials that cut the bacteria behind the smell, or fragrance that covers it, and it doesn't reduce sweat at all. A stick that does both jobs is a cosmetic and a drug at once.
Do natural deodorants stop sweating?
No, because none of them carries the aluminum salts on the FDA's list for over-the-counter antiperspirants. They work on odor and surface wetness instead. Baking soda and arrowroot are common powders, and essential oils often carry the scent. Those oils count as fragrance, and fragrance is the most common allergen in deodorants, so they're the ingredient to watch if your skin reacts.
What deodorant is best for sensitive skin?
Start with a fragrance-free one, since fragrance is the most common allergen in deodorants and essential oils count as fragrance. I'd also leave baking soda out while you test. Patch test a new product on the underside of your arm or the bend of your elbow, twice a day for seven to 10 days. That's the American Academy of Dermatology's method. If the spot reacts, wash it off and don't use the product again, and see a dermatologist if a rash keeps coming back.
Why do I sweat more in menopause?
Hot flashes and night sweats, also called vasomotor symptoms, are waves of warmth that can come with flushing and sweating. They're common. The Menopause Society says they affect up to 80% of women and last a mean of 7 to 10 years. No deodorant or balm changes a hot flash. They're a clinician's to manage, and hormone therapy is FDA approved as a first-line therapy, with two nonhormone medicines approved as well.
If you make your own tallow deodorant, what should you know?
The recipe is yours; we only know the limits of the fat. Tallow does nothing about sweat and carries no odor control of its own, so a homemade tallow deodorant works only as far as what you add: baking soda takes on odor and can sting, arrowroot absorbs a little, and magnesium hydroxide is the gentler route. Keep the jar out of the shower and use a clean finger; a balm with no water in it stays sound, but the water your hands carry in does not. If the skin stings or reddens, stop. The underarm is thinner than it looks.
Go deeper
The beef tallow for skin guide covers what a balm does do on skin. For the men's side of this, there's tallow balm for men. If your skin reacts to most things, you'll want tallow for sensitive skin and beef tallow side effects, which covers essential oil allergies. The two questions that usually sit behind the switch are answered in aluminum antiperspirants and cancer and baking soda deodorant and the armpit detox.
Sources
- Callewaert C and colleagues (2013). Characterization of Staphylococcus and Corynebacterium clusters in the human axillary region. PLoS One 8(8):e70538.
- American Academy of Dermatology (2021). How to test skin care products, page last updated August 10, 2021. AAD.
- US Food and Drug Administration (2026). 21 CFR part 350: antiperspirant drug products for over-the-counter human use, up to date as of October 1, 2026. eCFR.
- Natsch A and Emter R (2020). The specific biochemistry of human axilla odour formation viewed in an evolutionary context. Philosophical Transactions of the Royal Society B 375(1800):20190269.
- FDA (2024). Is it a cosmetic, a drug, or both? (Or is it soap?), content current as of September 11, 2024, read October 5, 2026. FDA.
- Zirwas MJ and Moennich JN (2008). Antiperspirant and deodorant allergy: diagnosis and management, full text as published on the journal's site. Journal of Clinical and Aesthetic Dermatology 1(3):38 to 43.
- Baker LB (2019). Physiology of sweat gland function: the roles of sweating and sweat composition in human health. Temperature, volume 6, issue 3, pages 211 to 259.
- The Menopause Society (2026). Hot flashes, an undated patient education page, read October 5, 2026. The Menopause Society.
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.