Forget roses and candlelight! When we fall in love, animal sniffing instincts take control. It’s not only over a candlelit dinner with glances and vows (as seen, for example, in the Dr. Oetker Ristorante pizza ad) that woman and man become lovers. That said, falling in love really does have something to do with your mouth watering: saliva proves whether a couple are biologically compatible. And not just saliva. To mark the beginning of spring, here’s a little olfactory birds-and-bees talk on falling in love!
Genetics: the bigger the difference, the better!
According to science, romantic bliss blossoms more intensely when couples show enough genetic differences. Social background also plays a part, but biology, with its focus on evolution, wants maximum genetic diversity. The decisive factor here is the MHC code (short for major histocompatibility complex). These proteins bind bacteria and viruses and boost the body’s own immune defences. In other words: the greater the number of different MHC proteins, the better a person copes with pathogens. If they mate with another biped who also has a high number of different genes, that’s the optimal combination from a biological point of view. Why? Because they bring stronger offspring into the world, who can adapt to their environment in more varied ways. Lovers who are too genetically similar, by comparison, produce weaker offspring.
You can smell the genes!
So how can you tell, without a gene test, whether you’re compatible or not? You like the way the other person smells! MHC genes apparently also influence body odour. A person’s individual pheromone cocktail gets delivered to the man or woman via the sweat glands. When you get close, you smell each other quite unconsciously, unless you actually have a good sniff first, if that doesn’t spoil the romance. When heads come together while flirting and hands and upper bodies touch, the smell, according to the University of Lausanne, is perceived by the vomeronasal organ on both sides of the nasal septum. From there, the scent notes travel as chemical messengers to the brain, which reacts with joy or rejection. Even before the first kiss, a man and a woman instinctively know whether they belong together. As the German saying has it, you have to be able to “smell” each other, which is our way of saying you can stand one another.
If all this is true, wouldn’t everything be quite simple?
Well, it isn’t. A number of scientific studies are under way on this subject, but the question of MHC genes & pheromones hasn’t really been settled yet. While pheromones have been shown to act as sex attractants in numerous mammals, it’s actually still unclear whether they even exist in humans. What is certain: every person has an individual scent, which is also influenced by their genes. Often it’s a mix of natural body odour and the detergent, shampoo, deodorant and perfume they use.
In conclusion: scent marketing, which you can control, probably does play a part after all. Whether it’s an aromatherapy room fragrance or a perfume, you shouldn’t leave your scent to chance!
University of Lausanne
