Formulation notes · No. 1

Why we built a deodorant around magnesium, not baking soda

The working notes behind Morrowen — written for the person who has tried three natural deodorants, gotten three rashes, and wants to know what's actually going on under their arms.

The problem we kept running into

Every "best natural deodorant" list has the same silent asterisk: works great, unless your skin is sensitive. The reason is almost always the same ingredient. Baking soda deodorizes brilliantly and costs nearly nothing, which is why it anchors most of the natural aisle. But it operates at a pH around 9 against skin that lives at 4.5–5.5, and on underarm skin — thin, occluded, frequently shaved — that gap becomes a rash for a meaningful share of people.

The industry's usual answer is a "sensitive" variant that just dials the baking soda down. Less irritant is still irritant. We wanted a different active entirely.

What magnesium hydroxide does differently

Body odor isn't sweat; it's what skin bacteria make of sweat. Anything that keeps those bacteria from thriving keeps you from smelling. Magnesium hydroxide does this by nudging the skin surface just alkaline enough to slow bacterial growth — a fraction of baking soda's alkalinity, with a far gentler footprint on the skin barrier. It's also poorly soluble, so it sits on the surface doing its job rather than soaking in.

Less irritant is still irritant. We wanted a different active entirely.

The trade-off is honesty: magnesium is a deodorizer, not an antiperspirant. You will still sweat — that's your body working. Arrowroot in the formula absorbs the moisture; magnesium handles the odor. For the mechanics of the two-week adjustment when you drop antiperspirant, see the switching map on our main page.

Why colloidal oat is in a deodorant at all

Colloidal oatmeal is the quiet hero of the formula and the reason Morrowen feels different on freshly shaved skin. Dermatology has leaned on it for decades in eczema and barrier-repair care: it buffers, calms, and supports the lipids your skin barrier is made of. In an underarm product it acts like a shock absorber between the active and your skin. As far as we can tell, almost nobody else builds a deodorant this way — which is roughly the story of why Morrowen exists.

The choices behind the rest of the list

Candelilla wax over beeswax keeps the stick vegan and gives a cleaner glide. Shea and jojoba carry the formula and condition skin without clogging. Calendula earns its slot as a skin-soother with a long topical history. Vitamin E keeps the plant oils fresh. And the scent — clover flower with a breath of fir needle, the "Fog & Clover" of the label — is deliberately faint, because we'd rather smell like nothing much than like a candle. The Unscented stick omits fragrance entirely, essential oils included, because "unscented but still has lavender oil" is a sensitive-skin betrayal we refuse to repeat.

What we left out, and why

No aluminum — that's antiperspirant chemistry, and plugging sweat ducts isn't our project. No baking soda, for everything above. No alcohol, which stings and dries. No probiotics or enzyme systems yet: interesting science, but we won't add an ingredient we can't stand behind for the most reactive decile of skin. Eleven ingredients is the whole list, and we intend to keep it boring.

Morrowen is a deodorant, not an antiperspirant, and nothing here is medical advice — if you have a skin condition, patch-test any new product inside the elbow for a few days first. Questions we haven't answered? The FAQ on the main page covers switching, staining, and scent.