Is Baking Soda Bad for Sensitive Skin? What You Need to Know

Baking soda has a pH of around 8–9. Your skin sits around 4.5–5.5. That's not a small gap. It's the difference between your skin's protective acid mantle staying intact and getting knocked off balance.

For a lot of people, that imbalance shows up fast:

• Redness and irritation
• Burning or stinging
• Rashes and contact dermatitis
• Over time, in some cases, patches of darker skin where the irritation kept coming back

Not everyone reacts. Some people wear baking soda deodorant for years without issue. But "some people are fine" isn't the same as "it's fine" and if your skin has ever gone from calm to angry a few days into a new natural deodorant, baking soda is the usual suspect.

Why It's Still Everywhere

Baking soda works. It neutralizes the bacteria that cause odour, it's cheap, and it's easy to source, which is exactly why it became the default in early natural deodorants. None of that makes it a good match for every underarm. It just makes it a convenient one.

What We Use Instead

Ditching baking soda doesn't mean giving up odour protection. It means picking ingredients that do the same job without the same fallout:

• Magnesium hydroxide — neutralizes odour-causing bacteria the same way baking soda does, but through a slow, steady release instead of a sharp pH spike. It's not a "gentler pH" as magnesium hydroxide is actually more alkaline than baking soda on paper. The difference is timing: it dissolves gradually in sweat instead of hitting your skin all at once, which is why skin that reacts to baking soda often tolerates it fine.
• Tapioca starch — absorbs moisture and keeps the formula gliding on instead of sitting gritty.
• Plant-based oils and emulsifiers — condition the skin instead of stripping it.

This is the formula we build BPM around. No baking soda. No aluminum. Zinc and magnesium doing the actual work, nothing extra along for the ride.

Check out our Sensitive Skin Deodorant collection or browse the full Natural Deodorant range.

How to Tell If Baking Soda Is the Problem

If a natural deodorant has left you red, itchy, or burning, baking soda is the most common cause. Reaction timelines vary. For some people it's days, for others it takes longer to build up so don't rule it out just because the first week was fine.

The upside: switching to a baking soda-free formula is usually enough to let skin recover. How long that takes depends on the person and how irritated things got, so we won't put a number on it we can't back up.

Bottom Line

Baking soda isn't dangerous. It's just not built for every underarm, and a lot of "natural deodorant doesn't work for me" stories are really "baking soda doesn't work for me" stories. If yours is one of them, the fix isn't giving up on natural deodorant, it's finding a formula that skips the ingredient causing the problem.