While working with International Fragrance and Flavors, the research psychologist Carol Christensen became fascinated by the effects of pheromones on other animals. When a female pig detects the pheromone androstenone (secreted in a male's saliva), for example, it will promptly assume a mating stance. "The dream of male humans," Christensen once remarked, "is that there would be such a compound [for them]." Unfortunately, she added, pheromones don't seem to have such effects on humans. Indeed, a man once asked her whether he should buy a pheromone product and received the reply: "Don't stop brushing your teeth."