One of the first impulses a person may get when someone with bad body odor crosses their path is to pinch their nostrils together with their thumb and index finger and swiftly move in the opposite direction. However, increasing exposure to foul smells may actually lead people to become more cooperative and supportive toward their unpleasant-smelling counterparts, according to a recent study.

Sweat and body odor stems from the body’s temperature regulation system, specifically the sweat glands. The Mayo Clinic says sweating helps maintain body temperature, hydrates the skin, and balances the bodily fluids, electrolytes, and chemicals in the body such as sodium and calcium. The body also secretes a fatty sweat when a person is under emotional stress. This stress is pushed to the surface of the skin where the bacteria begins to break down apocrine sweat, produced by the apocrine glands, which leads to an odor. A bad body odor is believed to be associated with vulnerability, which generates feelings of concern and pity from others, suggest Belgian researchers.

“Scents are omnipresent in our daily world, and they are of great importance as represented by the use of perfumes or fragrances in the work environment,” wrote Jeroen Camps and his colleagues in the report.

Published in the Journal of Applied Social Psychology, a team of Belgian researchers argued the effects of bad odor can elicit feelings of pity in others and increase prosocial behavior such as helping behaviors.

Thirty-six participants were randomly assigned into two groups where they had to imagine the item belonged to someone they worked with in the first experiment. Half of the volunteers were asked to sniff a bad-smelling t-shirt sprayed with human sweat, beer, and other foul smells, while the other half whiffed a more neutral-smelling t-shirt. All of the t-shirts in this experiment were of the same shape and color.

The researchers measured how the participants felt about the other person by rating the person from one — totally disagree, to five — totally agree. Their level of pity was measured by the following two statements: “I feel sorry for the other person" and “I find the other person pathetic.” The participants in this experiment with the malodorous t-shirt felt significantly more pity than those in the neutral condition, according to the Daily Mail.

The second experiment involved a total of 62 participants who were first asked to complete a maze alone before they were seated next to someone who was either wearing a neutral or bad-smelling t-shirt. After they were placed next to the neutral or bad-smelling participant, they were asked to complete another maze.

The volunteers were then moved to third room and were asked to divide the 11 credits among themselves and the other person for an opportunity to win film tickets. The researchers noted people who had sat next to a foul-smelling person were more inclined to donate more credits to the other person on average compared to their counterparts. This experiment proved an increase in prosocial behavior among people who were exposed to those with bad body odor, said the researchers.

Lastly, the third experiment included 42 participants who were more generous. They experienced elevated prosocial behavior when the researchers showed that the person was not held accountable for their own body odor. In other words, the participants were more generous and supportive when they were told people with bad body odor were not responsible for smelling badly, or that it was beyond their control.

“Even though it has been argued that bad scents invoke negative judgments, we argued and demonstrated that a bad body odor elicits feelings of pity in others and increases prosocial behavior,” the researchers wrote.

Overall, the researchers found these findings provide a novel perspective on the way human body odor can affect others’ perceptions and consequent behaviors.

The power of body odor can also extend itself to age. In a study published in the journal PloS ONE, researchers found the participants were able to correctly assign age labels to body odors originating from old-age donors but not to body odors origination from other age groups. The findings reveal humans are able to identify age based on body odor alone, which is mediated by body odors emitted by individuals of old age.

But for this study, bad odors, although typically associated with negative perceptions, showed to lead to people being generous, supportive, and even more understanding of individuals.


Camps, J, Stouten J, Tuteleers C et al. Smells like cooperation? Unpleasant body odor and people's perceptions and helping behaviors. Journal of Applied Social Psychology. 2013.

Gordon AR, Lundstrom JN, Mitro S et al. The Smell of Age: Perception and Discrimination of Body Odors of Different Ages. PloS ONE. 2013.