What makes someone smell good? How do we come to link everyday smells with particular people, and what's that indescribable something extra that makes a blanket smell like more than the sum of its parts? Not just soap and cologne, but him.
First discussed in 1959, the word pheromone originally referred to the unique chemical cocktails emitted by animals and detected by members of their own species. Essentially, a pheromone is a chemical combo that, when emitted by an animal and detected by the vomeronasal organ (located between the nose and mouth, which directs stimuli to the hypothalamus instead of the brain's cortex) of another, produces some kind of response -- either behavioral or physiological. We've observed specific pheromone release and response in many animals, but not in humans -- and while we may have vomeronasal organs, most argue that they're vestigial at best.
Regardless of the lack of evidence for these chemicals in humans, many companies market and sell products meant to boost sexual attractiveness based on the presence of so-called pheromones. James Kohl, a chemical researcher who now sells a line of such products, says that our lack of strict responses to certain chemicals doesn't indicate their nonexistence, but just a high level of self-control. He uses the analogy of food odors: Humans respond to them by salivating, but we can choose not to eat. "The truth," he says, "is that some people control themselves better than others. We're not like other animals, which is why we don't respond to pheromones like other animals!"
But Kohl's products, which he likens to food spices ("They give you an extra kick!"), make some researchers roll their eyes. Dr. Jim Pfaus, professor of psychology at Concordia University in Montreal, is one of them.
"Products containing 'pheromones' are meant to drive women crazy, and they might just work -- on female pigs," he says, referring to the steroid androstenone. Found in the saliva of male pigs, the smell causes females in heat to assume a mating stance. Because humans also produce it, mostly in their urine, researchers have tried to pinpoint it as a human pheromone. Dr. Tamsin Saxton, a psychologist from Northumbria University in Newcastle, UK, recently completed a study that suggested some positive effect on female human attraction to men after the application of androstenone on the upper lip, but stated in the paper that she and her colleagues "wish to distance ourselves from what we see as the naive search for a human sex pheromone that encapsulates much of the media's coverage of the research" and later said that what makes a human smell "good" is "harder to pin down" than many realize.