Female Armpit Odor May Influence Male Behavior

According to research from the University of Tokyo, female armpit odor during ovulation may influence men's perception and emotional state by reducing their stress levels and increasing attraction.

A recent investigation conducted by scientists at the **University of Tokyo** has shed light on the complex interaction between body odor and human behavior. The study suggests that certain compounds present in female axillary sweat, particularly during the ovulation phase, may have a discernible effect on men, influencing their attraction and lowering their stress levels.

## An Unexpected Finding

During the experiment, a group of male volunteers was exposed to samples of female armpit sweat. The results indicated that men not only showed greater attraction toward women associated with these odors but also experienced a decrease in their stress levels. Most surprisingly, this effect was significantly manifested only during specific stages of the female menstrual cycle. Specifically, men perceived women's faces as more attractive and feminine when the aroma of their armpits corresponded to the ovulation phase, the moment of maximum fertility. This perception was linked to hormonal changes that alter the chemical composition of sweat. Researchers observed a reduction in a stress biomarker in the saliva of participants exposed to these odors. According to Professor **Kazushige Touhara**, one of the principal authors of the study, these findings may indicate that body odor plays a role in communication between men and women, even at a subconscious level.

## A Complex Chemical Mixture

The detailed chemical analysis allowed the identification of three specific compounds that vary throughout the menstrual cycle and become notably intensified during ovulation. When these substances were added to axillary sweat, men reacted more positively to the aroma and found the female faces associated with the samples more attractive. This response may have an evolutionary basis, facilitating the unconscious identification of the optimal time for reproduction. Although it cannot yet be stated with certainty that these compounds function as human pheromones, the Japanese team suggests they may have a similar effect. However, **Touhara** emphasizes the need for further research to determine if these odors are exclusive to humans—a defining trait of pheromones in the animal kingdom. The logistics of sample collection posed a considerable challenge, requiring weeks of planning and precise monitoring of the hormonal stages of more than **20 women**.

## Human Pheromones? It Is Still Early to Say
Pheromones are a well-documented phenomenon in the animal kingdom, used by insects, birds, and mammals for various signals. In humans, evidence is more limited and often inconsistent. Previous studies have explored substances like **androstenone** or **estratetraenol**, but their results have been debated due to potential methodological issues. In this study, the researchers remained cautious. Despite the observed effects, **Touhara** reiterates that it cannot be definitively stated that these are pheromones. What is clear, however, is that certain compounds in axillary sweat during ovulation appear to influence male perception and emotional state. The team plans to expand the participant pool in future research to rule out genetic influences and analyze brain responses to these aromas more deeply, especially in areas related to emotion and sensory perception.