Scientists discover how women’s underarm scent affects men

A unique study conducted in Japan revealed surprising insights: men were asked to smell women’s underarms — and the results were more intriguing than expected.

Researchers from the University of Tokyo found that a woman’s body odor can influence male behavior, helping them relax and even enhancing their perception of female attractiveness — but only during certain days of the menstrual cycle.

A Scent That Soothes

According to the scientists, the underarm scent becomes especially appealing during ovulation, when the chance of conception is highest. At this time, a woman’s body releases specific compounds that transform ordinary sweat into a subtle chemical signal.

When these compounds were added to sweat samples, men consistently rated the smell as more pleasant and judged women’s faces as more attractive and feminine. Furthermore, saliva tests showed lowered stress levels among participants.

“These findings suggest that body odor may play a role in communication between men and women,” said Professor Kazushige Tohara, who led the study.

Is It Love or Pheromones?

While animals have long used pheromones to attract mates, evidence for their effects in humans remains inconclusive. Some studies have linked chemicals like androstadienone (found in male sweat) and estratetraenol (in female urine) to mood changes and altered perceptions, but these experiments often face methodological criticism.

To avoid such pitfalls, the Japanese team carefully tracked over 20 women’s body temperature and other cycle indicators, collecting samples on precisely timed days. Each observation cycle could last up to a month.

A Scent That Changes Perception

Though Professor Tohara hesitates to officially label these substances “human pheromones,” he acknowledges the discovery could be a significant step toward understanding how we perceive and choose partners. The researchers plan to expand the participant pool and investigate how the brain reacts to these scents.