You get out of the shower, clean t-shirt, deodorant on… and a few hours later, your armpits already smell. Many see this as evidence of sloppy toileting. This idea sticks to the skin and fuels embarrassment, guilt, even obsession with soap. What if it was simply false?
Bad body odors mainly result from the sweat–bacteria duo, modulated by genetics, hormones, clothes or sheets. Hygiene remains important, of course, but it does not explain everything. Understanding what is happening under the armpits or on the feet already allows you to relieve the pressure.
Bad body odor: what really happens to the skin
Sweat is almost odorless; what smells are the molecules produced when bacteria in the skin degrade it. Areas rich in apocrine glands, like the armpits, groin, or feet, provide warmth and humidity, an ideal combo for making more odorous compounds.
Under the arms, the microbiome is, describes pharmacist Marie Drago,: very humid, hidden, it is also there, with a high pH. This decor favors certain very odorous bacteria. And then, recalls Marie Drago, founder of Gallinée, quoted by Voici.
Genetics, hormones, textiles: why hygiene is not always enough
A gene like the ABCC11 gene influences the type of earwax and the intensity of axillary odors. Marie Drago even mentions a “gene that doesn’t smell”: , she explains. Same hygiene, different smell.
Hormones (puberty, pregnancy, cycle, menopause), stress or certain medications also modify the composition of sweat. Bad body odor can then worsen without any change in routine. If an odor suddenly becomes very unusual (fruity, fishy, ammonia) or is accompanied by other symptoms, it is better to consult rather than take more showers.
Bad body odor: act gently on the microbiota and daily life
Responding to the odor with ultra-stripping gels is not always a good idea. These products can unbalance the microbiota and allow “bad” bacteria to dominate the “good” ones. Marie Drago recommends treatments with an acidic pH, enriched with prebiotics, under the armpits, with occasional gentle exfoliation.
Madame Sweat recommends, in addition to shower gel, , she explained in Paris Match. For the armpits, she cites for example and specifies:
Do bad odors mean poor hygiene?
Often no: sweat, bacteria, genes or hormones are enough, even with good hygiene.
Why do my armpits smell so much?
Because this area is warm, humid, very bacterial, and your genetics can amplify the smell.
When to consult for body odor?
If the smell changes suddenly, becomes very strange or is accompanied by other symptoms, medical advice is required.
