A new study published in Evolution and Human Behavior provides compelling evidence that human body odor may act as a subtle cue for social status. Specifically, the research suggests that men with higher levels of testosterone produce a scent that others perceive as more dominant. These findings indicate that chemical signaling may play a role in how humans assess social hierarchies, operating largely outside of conscious awareness.
How Do Humans Signal and Perceive Social Status?
Social hierarchies form a fundamental aspect of human group living. To navigate these complex social structures, individuals must constantly assess the standing of those around them. Evolutionary psychologists generally categorize social status into two distinct strategies.
Dominance vs. Prestige: Two Paths to Social Power
The first strategy involves dominance, which relies on intimidation, force, or coercion to secure resources and compliance. In contrast, the second strategy focuses on prestige—a form of status that others grant freely to individuals who demonstrate valuable skills, knowledge, or wisdom.
While both strategies lead to high social rank, they manifest through different behaviors. For instance, dominance often appears through aggressive posturing and lower vocal pitch. Meanwhile, prestige connects closely to confidence and social connection.
Humans excel at reading visual and vocal cues to judge these traits. An expansive posture or a deep voice often signals high status. However, animals across the biological spectrum also rely heavily on chemical communication. From insects to mammals, organisms use scent to mark territory, find mates, and signal fighting ability.
Chemical Communication in the Animal Kingdom
Scientists have well-documented dominance signaling via scent in other species. For example, dominant male rodents mark their territory with urine to advertise their competitive strength. Subsequently, other males typically avoid these areas to prevent costly physical conflicts. Therefore, the authors of the current study sought to determine if a similar biological mechanism exists in humans.
What Role Does Testosterone Play in Dominance and Body Odor?
Researchers frequently associate testosterone, a hormone, with status-seeking behavior in men. Notably, scientists link it to aggression and the drive to achieve social power. Furthermore, biologically, testosterone influences physiological processes that create body odor. Specifically, it affects the apocrine sweat glands and triggers the production of sebum, an oily substance on the skin.
Because testosterone drives both status-seeking behavior and body odor production, the researchers hypothesized that the two might connect. They proposed that men with higher testosterone would produce a smell that others interpret as indicative of high social status. Specifically, they examined whether this scent would signal dominance or prestige.
“The human sense of smell is still not well understood, and people generally don’t recognize how much information we gather through our noses, or how impactful losing this sense can be,” explained study author Marlise Hofer, a postdoctoral researcher at the University of Victoria.
“Our motivation came from two converging observations. First, research is beginning to reveal that human odor cues carry a wide range of social information (e.g., emotional states, health, kinship), and we wanted to know whether this extends to perceptions of social status or dominance.”
“Second, prior work suggests that hormones such as testosterone play a role in status-related behaviors (competitiveness, dominance), so we wanted to examine whether testosterone levels, or scent cues associated with testosterone, might be involved in providing subtle olfactory information shaping perceptions of social status. In doing so, we bridge biological endocrinology, chemical communication, and social status perception, domains that all matter for understanding how people navigate hierarchies, competition, and social connection.”
How Did Researchers Test the Link Between Testosterone and Body Odor?
The researchers recruited 74 male participants to serve as scent donors. These men averaged approximately 22 years of age. To ensure outside factors didn’t contaminate the scents, the donors followed a strict hygiene protocol.
The 24-Hour Scent Collection Protocol
For 24 hours, the donors avoided activities that could alter their natural smell. Specifically, researchers instructed them not to smoke, drink alcohol, or eat strong-smelling foods like garlic or onions. Additionally, they refrained from using scented soaps, deodorants, or colognes. Instead, the researchers provided them with fragrance-free soap and shampoo for showering.
During this 24-hour period, each donor wore a clean, white cotton t-shirt. This allowed their natural body odor to accumulate on the fabric. Moreover, the donors visited the laboratory to provide saliva samples. Researchers then analyzed these samples to measure their circulating levels of testosterone.
After the team collected the shirts, they froze them to preserve the odors.
The Smell Rating Phase: 797 Independent Evaluators
The second phase of the study involved a large group of independent raters. The researchers recruited 797 participants to act as “smellers.” This group included both men and women.
The smellers received the worn t-shirts, as well as unworn control shirts. Importantly, researchers told them nothing about who wore the shirts or provided any information about the donors. For each shirt, the rater inhaled the scent and completed a questionnaire.
What Did the Raters Evaluate?
The questionnaire asked the smellers to rate the odor on several dimensions:
| Rating Category | What Raters Measured |
|---|---|
| Intensity | How strong the smell was |
| Pleasantness | How pleasant or unpleasant the odor was |
| Sexiness | How attractive the scent was |
| Dominance | Aggressive control traits (e.g., “enjoys having control over others”) |
| Prestige | Respect-based traits (e.g., “held in high esteem by others”) |
The items used to assess dominance focused on aggressive control. For example, raters considered whether the wearer seemed like someone who “enjoys having control over others.” In contrast, the prestige items focused on respect, such as whether the wearer seemed “held in high esteem by others.”
What Did the Study Reveal About Testosterone and Perceived Dominance?
The researchers analyzed the data using multilevel modeling. This statistical approach allowed them to account for the fact that multiple people rated each shirt. Significantly, the analysis revealed a positive association between testosterone and perceived dominance.
Key Findings: Higher Testosterone Equals More Dominant Scent
Men who had higher levels of testosterone produced sweat that raters perceived as coming from a more dominant individual. Importantly, this relationship held true even after the researchers controlled for the intensity of the smell. In other words, while high-testosterone sweat smelled stronger, the perception of dominance did not solely depend on the strength of the odor.
Additionally, the researchers found that testosterone levels positively correlated with scent intensity. Men with more testosterone simply smelled stronger. However, testosterone showed no significant relationship with how pleasant the smell was. Therefore, the hormonal signal appeared to convey information about power rather than attractiveness.
Dominance vs. Prestige: Different Biological Signals
The findings regarding prestige differed distinctly from those regarding dominance. Specifically, the researchers found no association between a donor’s testosterone levels and how prestigious others perceived them to be. This aligns with evolutionary theory suggesting that dominance represents a more primal strategy rooted in physical aggression. Conversely, prestige, being a more culturally dependent trait, may not signal as directly through biological markers like testosterone.
Self-Perception Doesn’t Match Others’ Perceptions
The researchers also examined the donors’ self-views. The men completed surveys rating their own levels of dominance and prestige. Interestingly, the analysis showed no correlation between a man’s self-rated dominance and his testosterone levels. Furthermore, a man’s self-view did not predict how others rated his scent. This suggests that while testosterone influences body odor in a way that signals dominance to others, this signal operates independently of how a man sees himself.
What Are the Broader Implications of This Research?
Together, the findings provide evidence that “humans can detect and respond to subtle differences in body odor, and those differences can influence how dominant someone appears to be,” Hofer told PsyPost. “Scent is one more input into how we understand and respond to others, and because odor perception often operates outside conscious awareness, it’s an important but understudied part of social interaction.”
The Effect Size: Small but Significant
However, it is important to note that “the effects were small. This doesn’t mean people can clearly ‘smell status,’ but rather that scent contributes one subtle cue among many. It’s an incremental insight: the effect is real but limited, and in everyday interactions context and other sensory or social cues likely play a much larger role.”
Does Gender of the Smeller Matter?
Notably, the researchers found that the sex of the smeller did not affect the results. Both male and female raters perceived the scents of high-testosterone men as more dominant.
“All our odor samples came from male donors, but our raters included both males and females,” Hofer explained. “We were surprised that the effect of testosterone did not differ based on rater sex. Females typically have a stronger olfactory ability, so we initially expected they might show stronger effects. We also thought ratings might differ due to differing evolutionary goals related to mating or competition. However, there was no moderation by sex, suggesting that testosterone’s influence on odor perception remained consistent across males and females.”
What Are the Study’s Limitations and Future Research Directions?
As with all research, several limitations deserve consideration. First, the sample size of 74 scent donors remains relatively small for this type of research. While the number of raters was large, the number of unique scent profiles was limited. Therefore, replicating the study with a larger group of donors would help confirm the reliability of the association.
Single Hormone, Single Time Point
The study also focused on a single hormone measured at a single point in time. However, testosterone levels can fluctuate throughout the day. Consequently, a more comprehensive approach would involve measuring testosterone over several days to get a baseline average. Additionally, other hormones like cortisol likely play a role in social signaling.
The Testosterone-Cortisol Interaction
Future research could investigate the interaction between testosterone and cortisol. Indeed, previous work suggests the ratio of these two hormones predicts aggressive behavior better than testosterone alone. It is possible that the “scent of dominance” reaches its peak potency in men with high testosterone and low cortisol.
Understanding the Biological Mechanism
The biological mechanism behind this phenomenon also requires further study. Scientists know that testosterone stimulates hair growth and sebum production. Therefore, it is possible that these secondary factors drive the perceived dominance rather than the sweat itself. For instance, more underarm hair provides more surface area for bacteria, potentially intensifying the odor.
What’s Next for Olfactory Research?
Determining the exact biological roots of these signals remains a task for future science, but the results suggest that body odor provides a stream of social data. Hofer explained that she is now turning her attention to the consequences of losing access to that information:
“Since COVID-19, many people have temporarily or permanently lost their sense of smell, and I am increasingly focusing on the consequences of losing this important source of social and environmental information,” Hofer noted. “I would like to better understand these impacts and develop ways to support people living with olfactory dysfunction.”
Citation
Study Title: “The role of testosterone in odor-based perceptions of social status“
Authors: Marlise K. Hofer, Tianqi Peng, Jennifer C. Lay, and Frances S. Chen
Published In: Evolution and Human Behavior
