Nécessaire's Extra-Strength Deodorant Outlasts an Editor's Sweatiest Test: Fashion Week

Before boarding my 3,483-mile flight to cover Copenhagen Fashion Week for Marie Claire this weekend, I triple-checked my Tibi x L.L.Bean carry-on for three essentials. First, my lip and face masks (for beauty sleep); second, my Kindle (to tear through this year's best fantasy books when I couldn't actually sleep); and third, Nécessaire's new deodorant (for ensuring I stayed fresh once my feet hit the ground). That final packing list item had only been in my routine for a matter of days, but it had already earned plus-one status for my week of runways and designer interviews.

Nécessaire's entire lineup of hair, body, and skincare prides itself on "responsible luxury": formulas that look and smell like a rich-girl perfume or shampoo, but with granola, B-Corp-certified ingredients. The brand's new deodorant, released for $22 a tube at Sephora, Amazon, and its online boutique, promised to bring the same standards to the underarms department. Out with potentially harmful baking soda, aluminum, and parabens; in with gentle mandelic acid and odor-controlling vitamins B3 and B5. Plus, packaging that's sleek and minimal enough to pair with a Scandi-chic bag—not that I would need to carry it in my purse. With its promised 72-hour odor control, I could, supposedly, swipe it on once and be set for days (plural).

The Nécessaire deodorant landed on my desk with a handful of days until my busiest season of the year. So I put it to the test before packing it in my suitcase, swapping out the run-of-the-mill drugstore deodorant I normally wear with Necessaire's for both workday morning and pre-workout application. (I'm a marathon runner; I sweat a lot even when I'm standing still, and I usually can't make it 24 hours on one roll.)

I started each day with two swipes of the Eucalyptus-scented version under both arms. The aroma is day-spa strong: It's calming and bright, but overpowering enough that I decided to skip a few wrist taps of my favorite fragrance.

The deodorant comes in a solid block that liquifies when it hits the skin. It's quick-drying and doesn't leave any residue in the immediate aftermath. I'll have to admit that there was a bit of a tingling sensation when I wore it post-shave, too. While the ingredients are supposed to be skin-sensitive, they caused slight irritation on day one. But most importantly, for my purposes, it stays put.

The deodorant's fragrance slightly lost strength by the end of each work-week day packed with meetings, deadlines, and more meetings. But there wasn't body odor in its place. What came out of the tube with the force of a Macy's perfume counter spritz eventually settled into a lighter, natural-but-better scent. I checked the insides of my winter sweaters when I changed into pajamas to see if any sunflower wax got left behind. Aside from slight marks on a dark cashmere sweater, it played nicely with my knitwear and T-shirts. That was enough for me to ditch the dubiously formulated deodorants from my nearest CVS for something that felt (and looked) more luxurious.

Cut to the present: I made it through my first two days back on the runway grind with clean sleeves—even when some last-minute deadlines and between-show traffic sent my cortisol spiking. Still, no one at fashion week seemed to guess I was breaking a sweat.

Shop Nécessaire's Entire Deodorant Line