If you go on a date and wear perfume with pheromones, what are the chances that your date will like me more than if you hadn’t?
According to a less-than-scientific study by ABC’s 20-20, apparently the chances are good. The study sent two sets of twins, one male and one female pair, to an evening of speed dating. One twin in each set had perfume, one with pheromones and one without. At the end of the night, the one wearing pheromones in both sets got more interest than the others (ABC).
But there are several things wrong with this study. Aside from the drastically small sample size (two sets of twins and ten potential dates), it also doesn’t account for other factors. For example, there was little information on whether one of the scents, regardless of pheromones, was more appealing. Or even whether one twin is naturally more confident than the other.
And yet, busting the study’s legitimacy doesn’t mean that pheromones don’t have an effect, only that this study doesn’t prove it. Do humans really emit chemical signals that encourage attraction? And can this effect be faked with fragrance? What the studies do show are very mixed results that suggest that scent affects humans, but that the relationship is more complex than a simple spritz. In fact, it’s not totally accepted that humans have pheromones, and if we do, we don’t quite know exactly how they might affect us.
What are Pheromones?
To understand what pheromones are, it helps to break down the word itself. The first half comes from the Greek word “pheran” meaning “to transfer” and the second half comes from the Greek word “horman” meaning “to excite” (The Gale Encyclopedia of Science). Pheromones are used to convey messages about territory (think of dogs peeing to “mark their territory”), danger, trails, social situations, and sex. But most often the excitement that we talk about pheromones transferring is that of the social and sexual kind (Black’s Medical Dictionary).
Pheromones are detected by the vomeronasal organ (VNO), which then sends messages to the hypothalamus in the brain. This, in turn, causes the hypothalamus, which influences the pituitary gland responsible for potentially-behavior-affecting hormones. Scientists once thought that humans did not have the VNO, but tests in the 80s and 90s suggested, though did not prove, that we might have this apparatus. This is further complicated because some animals use their main olfactory epithelium to sense pheromones doesn’t necessarily preclude humans from using pheromones.
Human pheromones have been discovered in human urine and perspiration. Still, whether or not humans use pheromones continues to be under scrutiny by the scientific community.
We do know, however, that pheromones are quite powerful in animals. For example, a deer has seven different sites on the body that produce pheromones and each signify something different (Penguin Dictionary of Biology). And insects use pheromones particularly often, with the male silkworm moth smelling a female’s pheromones at a distance of up to one mile.
Are Humans Affected by Pheromones?
While there isn’t consensus, the answer is that it’s very possible.
You may have heard of the phenomenon of women living in close quarters all become synchronized in their menstrual cycle. That theory, first explored by psychologist Martha McClintock, PhD at the University of Chicago, demonstrated how these signals could affect the body (American Psychological Association). This doesn’t necessarily prove the existence of pheromones, but it does present a case where they might be at play.
A study at the University of Utah show that humans not only have VNOs but that this was a channel through which androstadienone and estratetraenol affected men and women. However, the University of Utah’s investment in a pharmaceutical company that worked with pheromones rendered many scientists skeptical of this data.
But other studies have shown that scent plays a big role in attraction. For example, the scent of tears is a “turn-off” to men, i.e. when they smell tears they have decreases in arousal and testosterone. If there are scents that turn people off, scientists think it’s likely that there are scents that turn people on. Just because we haven’t found it doesn’t mean it doesn’t exist.
A study at the Karolinska Institute in Sweden found that men produce androstadienone and that women produce estratetraenol, Conversely, androstadienone only increases the activity of women’s hypothalamus and estratetraenol only increases the activity of men’s hypothalamus. Though, studies that have shown that whom you’re attracted to counts as well, as gay men are affected by androstadienone. A study on gay and straight men have found that gay men prefer the scent of gay men’s sweat while straight men prefer the scent of women’s sweat (Smithsonian Magazine). And women preferred the sweat of men with diverse enough genetics from their own that they were likelier to produce a healthy child.
Future studies will help to confirm whether or not pheromones exist for humans and to what extent they affect behavior.
Do Pheromone Perfumes Work?
Whether or not pheromones perfumes work depends primarily on your thoughts on how exactly they should work. If someone wears the perfume, has more confidence, and subsequently seems more desirable because of that self-assurance, then the perfume has worked at increasing their attractiveness. But if “working” means that the scent itself makes someone more attractive, then the answer is less clear.
It’s important to take into account that certain scents, such as those in perfume can boost moods on their own. So receiving a positive reaction from the wearing of a fragrance is not the same as having a pheromone response. This is an important distinction. In order to test the effectiveness of pheromones, it would be necessary to test human putative pheromones on their own (The Journal of Steroid Biochemistry and Molecular Biology).
These perfumes contain putative pheromones, which means the chemicals that are reputed, but not proven, to be human pheromones. While these — androstadienone and estratetraenol — undoubtedly have an effect, it’s not certain that the effect is to make someone more attractive.
For example, androstadienone enhances women’s moods and causes them to give emotional stimuli greater attention (University of New South Wales). But that doesn’t mean that a woman will become hopelessly attracted to a man to whom she is not attracted to in the first place. There are no statistically significant studies that have proven that pheromones in perfume make the wearer more attractive to the opposite sex (Psychology & Behavior). Studies have found that women only demonstrate a response to androstadienone when a male tester ran the session. And the aforementioned fact about women’s attraction to the scents of men who are genetically diverse shows that there are complex factors at play.
Essentially, while the scent may have an effect, social context and social complexity have both been suggested as important factors in whether or not putative pheromones are effective.
Before one can even determine that pheromone-containing perfumes have an effect on the wearer’s attractiveness, it’s important to determine exactly what effect the reputed or putative human pheromones have on behavior. In animals, pheromones work to send all sorts of signals and messages and it’s thought that humans have this ability to sense through smell as well.
Essentially, these scents affect the hypothalamus, which affects the pituitary gland, which sends hormones in the body that can influence certain behaviors. However, research shows that the science of scent is more complex than just dousing yourself in pheromone-containing perfumes to garner a reaction. For example, women can smell genetic diversity in potential partners and find that to be attractive, for which the pheromones in perfume cannot account. Beyond this, good smells can elicit positive responses that aren’t necessarily pheromone responses.
Uncovering the complex relationship between scent and socializing will help us determine how it plays into our daily lives. But the bottom line is that there isn’t enough research to understand whether pheromone perfumes work or even how they might work if they do.