Surprisingly, it seems this study proved just the opposite about men and women. While both sexes saw a drop in corisol while kissing, it appeared that only men experienced a raise in oxytocin. Women—forever desiring more, more, more—needed "a romantic atmosphere of dimmed lights and mood music" to notice any cortisol upswing.
We love this. This inherent appreciation of candle-lit dinners and nice bed sheets—it's in our blood we tell you! Guys, I hope you're reading, this is some important, learned stuff.
Scientists aren't sure why this happens. They think maybe because of pheromones (but we don't really buy that those exist). Most likely it's because, as scientists point out, kissing boosts the body's immune system due to all the mixing and matching of different strains of saliva.
So, just try to tell yourself that next time you make out with someone you regret—they may have helped you fight off a future cold or flu virus.