Can Changing Your Own Odor Change the Impression Your Behavior Makes?

If your own odor changes, can that affect the impression you make on someone who cannot smell you? In a 2009 study, men who used a deodorant containing fragrance and antibacterial ingredients were rated as more attractive in silent self-introduction videos than men who used a spray without those ingredients. No clear difference was found for photographs or videos with sound.

The study aimed to examine both users’ self-perceptions and the impressions others formed from their behavior. Rather than fragrance directly attracting another person, it focused on possible effects through how users felt about themselves.

Asking 35 men to use two different sprays

The participants were 35 men aged 19–35 from a UK university, all heterosexual nonsmokers. They were allocated alternately in recruitment order: 18 used a formula containing fragrance and antibacterial ingredients, and 17 used a formula without them. The latter still contained ethanol and propellant gas.

The containers were identical-looking white cans. The experimenter did not know the allocation, and participants were not told the detailed hypothesis or design. The original paper describes the manipulation as double-blind, but the procedure did not make the presence or absence of fragrance imperceptible.

At the first visit, the men completed baseline questionnaires. At a visit about 24 hours later, they used the spray and completed the questionnaires again 15 minutes afterward. For the following 48 hours, they replaced their usual deodorant with the assigned product, then completed final questionnaires and were filmed at a third visit. Most participants habitually used deodorant.

A difference in self-confidence, but only a trend in self-rated attractiveness

Self-confidence was assessed using a combined score from seven scales covering self-esteem, self-efficacy, assertiveness, and other aspects. The men were also separately asked to rate the attractiveness of their faces and bodies and their overall appearance.

Changes in self-confidence over time differed significantly between the formula groups. The fragrance-and-antibacterial group showed a relative increase compared with the control group, and the between-group difference in change from baseline to 15 minutes after use was also significant.

For self-rated physical attractiveness, however, the time-by-group interaction was p = 0.085, which did not meet the conventional 5% significance threshold. Comparisons from baseline to the final visit were also nonsignificant trends for both self-confidence and appearance ratings. Although the original abstract and conclusion make stronger statements about effects on both outcomes, the individual results provide clearer evidence for self-confidence.

Differences in impressions even through videos that conveyed no scent

At the final visit, the men imagined introducing themselves to an attractive woman and recorded a short video on their own. The assessment used the 15 seconds after they sat down and began speaking. A neutral-expression facial photograph was also taken. The videos showed the men from waist to head, allowing expressions, posture, and movement to be seen.

Eight other women used seven-point scales to rate attractiveness in photographs and attractiveness and apparent confidence in videos. They viewed the photographs first, followed by videos with and without sound in a counterbalanced order. The raters could not smell the men.

Attractiveness ratings for silent videos were significantly higher in the fragrance-and-antibacterial group than in controls. By contrast, there were no clear group differences in facial-photograph attractiveness, attractiveness in videos with sound, or confidence judged from videos. Importantly, the findings do not mean that men whose self-confidence increased necessarily looked more confident to others.

Product liking was also associated with video attractiveness

The researchers also calculated video attractiveness predicted from facial-photograph attractiveness and examined how much the actual video ratings exceeded that prediction. The fragrance-and-antibacterial group scored higher on this measure as well.

There was also a small positive association: men who liked their spray more tended to receive higher video-attractiveness ratings relative to predictions from their photographs. The authors interpreted this as supporting a possible link between users’ feelings about a product and their nonverbal behavior.

However, the study did not analyze which expressions or movements changed. Nor can the association between liking and video ratings by itself establish the mechanism through which liking might change behavior.

Was fragrance or antibacterial action responsible?

The formulas differed in antibacterial ingredients as well as fragrance. Because neither body-odor intensity nor underarm bacterial levels were measured, effects of enjoying the fragrance cannot be separated from those of suppressing body odor. The authors suggest that fragrance may be involved in the early change at 15 minutes, but this is an inference from timing.

To avoid effects of becoming accustomed to filming, videos were recorded only once, after the intervention. Pre-existing behavioral differences between groups could therefore have remained. Adjustment using photograph ratings helps address this concern, but the study did not directly compare before-and-after videos.

Some men received comments about the product from other people during the study. In addition to effects of smelling the fragrance themselves, responses from others could have contributed. With its small sample, this study is a starting point for investigating the links between self-perception and impressions.

Summary

Compared with the formula lacking fragrance and antibacterial ingredients, the spray containing them produced changes toward relatively higher self-confidence in men. Female raters who could not smell the men also found the product group more attractive in silent videos. However, group differences in photographs, videos with sound, and apparent confidence were not clear.

How a fragranced product feels to its user may relate to interpersonal impressions through pathways other than the scent itself reaching another person. While suggesting that possibility, the study also highlights the need to distinguish fragrance from antibacterial action, and users’ self-ratings from other people’s evaluations.

The acknowledgments report that Unilever Research & Development supplied the fragrance, and two authors were affiliated with the company at the time of the research. Royal Society support for one author is also mentioned. No separate conflict-of-interest statement was found in the article text.

Reference

Roberts SC, Little AC, Lyndon A, Roberts J, Havlíček J, Wright RL. Manipulation of body odour alters men’s self-confidence and judgements of their visual attractiveness by women. International Journal of Cosmetic Science. 2009;31:47–54. doi:10.1111/j.1468-2494.2008.00477.x (Author-hosted full text)