Lume and Zaffré get compared often because both make strong claims about odor control without aluminum, and both talk openly about the science. That's where the similarity ends. The two attack body odor with almost opposite chemistry, and which fits you depends on your skin, your use case, and your scent tolerance.
You want one product marketed for use beyond underarms, you like a cream format, and acid-based skincare agrees with your skin.
You want a purpose-built underarm stick with a zinc-based system, a genuinely fragrance-free option, and a formula with no AHAs and no baking soda.
Two opposite mechanisms
Its key active is mandelic acid, an AHA that lowers skin pH so odor bacteria struggle. Physician-developed and real, but acids can sting on freshly shaved skin.
The BioShield system uses zinc to bind and hold the odor compounds bacteria release, no AHAs, no baking soda, and Dermatologist Tested.
The full mechanism is in How Zinc Stops Body Odor, and if you're weighing mineral actives, see Magnesium vs Zinc.
Scent, and the absence of it
Ask around and you'll find scent is the single most polarizing thing about Lume. Some people are fine with it, others find it hard to get past. Zaffré went the opposite direction: Sensitive has a fragrance-free option, with no scent blend added at all and nothing there to mask anything, because the zinc does the work. Core and Max come in Clean Slate, a soft powder scent built to fade rather than linger. Want something more botanical? Tea Tree keeps it light.
Sensitive skin
Acid on sensitive underarm skin can sting, a common complaint with AHA products. Zaffré's BioShield formulas are Dermatologist Tested, with no AHAs and no baking soda, and Sensitive goes further still: no alkaline active at all, not even magnesium. No sting, no burn, no grit.
Find your Zaffré fit in the buyer's guide.