Scientists have proven that male sweat contains a compound capable of lightening women's mood and increasing their sexual arousal. Researchers believe that we release odors containing pheromones in many different areas of our body, including the armpits, back sweat, and earwax. But men's armpits are particularly powerful. When women smelled men's armpits, they reported feeling less tense and more relaxed, Wysocki said.
That smell can also cause changes in women's menstrual cycles, Preti added. Most of our strong body odor comes from a kind of sweat that comes out of the apocrine glands in the armpits. The apocrine glands are activated during puberty and are primarily responsible for turning the armpits into stinky areas from adolescence onward. Meanwhile, the salty substance that flows when we exercise or overheat arises from a different and more abundant sweat gland, the eccrine gland.
Most of us have between 2 and 5 million eccrine sweat glands scattered throughout our bodies, including the armpit. The evaporation of water in this salty sweat draws heat away from the skin to cool us down; it's our main defense against potentially life-threatening heatstroke. The study focused on androstadienone, considered a male chemical signal. Previous research had established that its smell affected women's mood, sexual and physiological arousal, and brain activation.
Its impact on hormones was less clear. A derivative of testosterone, it is found in male sweat, as well as in saliva and semen. As a professional olfactory at the New Jersey-based company Sensory Spectrum, she smells things for a living, to help companies evaluate the aromas of a new coffee infusion, or to assess whether a deodorant successfully blocks body odor. Law enforcement officers have long realized that people who arrive for questioning smell of their own personality, but leave with a very similar smell after the stressful interrogation.