I would like to focus your attention on a research made by an italian scientist...
Thanks to accurate researches an italian paleo-bothanic - Giorgio Samorini - reveals to us that lettuce was a sexual stimulator for the Egyptians. In fact, Min, the deity of fertility, always appears sexually excited in all the bas-reliefs; in front of him there are males devoted to him, and each of them have lettuce on their hands. When they offered it to Min, he felt enthusiastic. Even when people used lettuce to stimulate sex, but it was not successful, they asked for Min's help, by offering lettuce to him.
In ancient times if latex was taken in low quantity, its property was that to calm people; on the contrary, if it was taken in large quantity, it occurred as to Min.