--- title: "Is Baking Soda Bad for Your Skin? What the Research Says" description: "Is baking soda bad for your skin? It is alkaline (pH ~9) and skin is acidic (pH 4.5-5.5), so it can irritate, especially leave-on in deodorant. The dose-dependent research, explained." url: https://whollykaw.com/learn/is-baking-soda-bad-for-your-skin published: 2026-07-14 updated: 2026-07-14 keywords: ["is baking soda bad for your skin", "side effects of baking soda on skin", "baking soda skin pH", "is baking soda bad for your skin deodorant", "baking soda in natural deodorant", "baking soda rash underarm", "baking soda acid mantle", "sodium bicarbonate skin", "side effects of baking soda on face", "baking soda free deodorant"] author: "Sri" site: WhollyKaw --- # Is baking soda bad for your skin? *Is baking soda bad for your skin? It is alkaline (pH ~9) and skin is acidic (pH 4.5-5.5), so it can irritate, especially leave-on in deodorant. The dose-dependent research, explained.* General information, not medical advice. This page describes published research about skin, sweat, and ingredients. It has not been evaluated by the Food and Drug Administration and is not intended to diagnose, treat, cure, or prevent any disease. For a sudden or persistent change in body odor, or a skin reaction, see a qualified professional. For many people, yes. Baking soda is alkaline, with a pH around 9, while the surface of healthy skin is mildly acidic, around pH 4.5 to 5.5. Putting an alkaline powder on acidic skin can disrupt the skin's protective barrier and cause dryness or irritation, and the risk is highest on sensitive skin and in leave-on uses like deodorant. The research is dose-dependent: diluted, occasional contact is lower-risk than daily leave-on use on thin, freshly shaved underarm skin. ## Is baking soda bad for your skin? It depends on the concentration, how often you use it, and where. As a rare, well-diluted rinse-off, baking soda is low-risk for most people. The problems show up with strong pastes, daily use, and leave-on application, because baking soda's alkalinity works against the skin's naturally acidic surface. People with sensitive, dry, or eczema-prone skin react most easily. The single highest-risk scenario is a common one: baking soda left on the underarm all day in a natural deodorant. ## The acid mantle: skin pH vs baking soda pH The outer surface of skin carries a thin, slightly acidic film often called the acid mantle. Research puts healthy skin surface pH on average below 5, roughly in the 4.5 to 5.5 range, and that acidity is not incidental. It supports the skin barrier and favors the balanced community of microbes that live on healthy skin. Baking soda, which is sodium bicarbonate, sits near pH 9 on the same scale. Because pH is logarithmic, that is a large gap. Applying an alkaline material repeatedly can push the skin surface away from its normal acidity, and the skin then has to work to recover. ## What baking soda can do to skin Dermatology sources and skin-pH research describe several effects when baking soda is used often or left on: - **Barrier disruption.** Shifting the surface pH upward can weaken the barrier that holds moisture in and keeps irritants out. - **Dryness and irritation.** Stripping surface oils commonly leaves skin feeling tight, dry, or raw, and can cause redness. - **Microbiome disturbance.** The acidic surface favors balanced skin flora, so raising pH can unsettle it. - **Micro-abrasion.** Used as a gritty scrub, the particles can cause tiny surface scratches. These are described in the research as effects on the skin barrier and surface chemistry. They are not the same as a medical condition, and reactions vary widely from person to person. ## Who is most likely to react Not everyone reacts the same way. The people who tend to have the most trouble with baking soda on skin are those with **sensitive skin**, **dry skin**, or an **eczema-prone** or already-compromised barrier. On those skin types, the margin before irritation is smaller, and leave-on or frequent use is more likely to cause a reaction. ## Baking soda in natural deodorant: the underarm angle Baking soda is popular in natural deodorants because it neutralizes acids and helps with odor. The trouble is that the underarm is close to a worst-case place to leave an alkaline powder. Underarm skin is thin and often occluded in a warm, humid fold. Many people shave it, which briefly compromises the barrier. It is under friction from arm movement. And a deodorant is left on all day, every day, which is very different from a rinse-off scrub used now and then. That combination is why a share of people tolerate baking soda deodorant at first and then develop irritation over weeks. It is also why **baking-soda-free** formulas exist. If baking soda has bothered your underarms, see our explainer on [baking-soda-free deodorant](/learn/baking-soda-free-deodorant) and on [natural deodorant for sensitive skin](/learn/natural-deodorant-for-sensitive-skin). ## What a baking soda reaction on the underarm looks like People describe underarm reactions to baking soda as redness, a burning or stinging feeling, itchiness, dryness, a rash, or a raw texture. A notable pattern is delayed onset: the deodorant feels fine for days or weeks, then the skin starts reacting, which is consistent with sensitization building up over repeated exposure rather than an instant burn. If your underarms react, stopping the product usually settles things, and a persistent or severe rash is a reason to see a professional. This is general information, not medical advice. ## When baking soda is lower-risk It is worth being honest about the nuance, because most popular articles say baking soda is simply bad. A 2024 review in the Journal of Integrative Dermatology found that diluted, low-concentration baking soda carries little risk of irritation, and that reported harms came mainly from excessive or prolonged use. So the accurate picture is not that baking soda is universally toxic. It is that concentration, frequency, and location decide the risk, and that daily leave-on use on thin, shaved underarm skin is exactly the high-risk end of that range. A once-in-a-while diluted rinse is a very different thing from a daily deodorant. ## Gentler alternatives If you want odor control without the pH mismatch, several ingredients work at a skin-friendlier surface. Magnesium hydroxide is a common, better-tolerated substitute for baking soda in deodorants. Arrowroot and other starches absorb moisture. Zinc compounds are used to manage odor. Many baking-soda-free deodorants combine these instead. If you are switching, our guides to [switching to a natural deodorant](/learn/how-to-switch-to-natural-deodorant) and [aluminum-free deodorant](/learn/aluminum-free-deodorant) walk through what to expect. ## Frequently asked questions ### What happens if I wash my face with baking soda every day? Daily use is the higher-risk pattern. Skin is meant to be mildly acidic (pH about 4.5 to 5.5) and baking soda sits near pH 9, so repeated use can raise the skin's surface pH and lead to dryness, tightness, and irritation, especially on the face and on sensitive skin. Dermatology sources generally advise against using it as a daily face wash or scrub. ### Is baking soda safe to use in deodorant? It is the highest-risk everyday use, because it is left on thin, often shaved underarm skin all day. Some people tolerate it, and others develop redness, itching, or a rash, sometimes only after weeks of use. If baking soda has irritated your underarms, a baking-soda-free deodorant avoids the pH mismatch while still addressing odor. ### Does baking soda remove wrinkles? No. That is a myth. Baking soda does not remove wrinkles, and its alkalinity and abrasiveness can irritate skin and disturb the barrier, which is the opposite of what aging skin needs. Gentler, pH-appropriate options are a better choice. ### Can I use baking soda on my underarms every day? Daily leave-on use on the underarm is the scenario research flags as most likely to cause irritation, because the skin there is thin, occluded, often shaved, and exposed all day. Occasional diluted use is lower-risk, but for a daily product, a baking-soda-free formula is the gentler route for most people. ### Is it better to soak in Epsom salt or baking soda? They are different. Epsom salt is magnesium sulfate and is closer to neutral, while baking soda is alkaline. For a plain soak, Epsom salt is less likely to shift skin pH. Either way, a short, well-diluted soak is far lower-risk than leaving concentrated baking soda on the skin.