Sweat serves two key purposes: regulating body temperature and flushing out toxins. Armpits host around 400 sweat glands per cm²—more than anywhere else on the body. Eccrine glands respond purely to temperature, producing sweat that's 99% water. Apocrine glands, however, secrete a thicker, oilier sweat triggered by stress, climate, diet, or hormones. Sweat itself is odorless; it's the bacteria in your armpits that create the smell upon contact. Deodorants curb bacterial growth and add fragrance, while antiperspirants cut sweat production by up to 50% alongside deodorizing.
If your deodorant or antiperspirant seems ineffective, consider these common culprits: 1) You've stopped noticing the scent? That's olfactory habituation—your brain adapts, just like with perfume. 2) Seeing stains or wetness? External factors like hotter weather, stress spikes, spicy foods, or hormonal shifts boost apocrine gland activity. The product's efficacy remains constant; you're simply sweating more.
For scent fatigue, switch to a different fragrance in the same line or try a new brand to refresh your senses. If sweat volume is up, reapply antiperspirant midday after cleansing your underarms (wipes work great on the go).
Insights from Annabel Mari, Scientific Director at Narta and Cadum.
