Caviar is high in zinc, which stimulates the formation of testosterone, maintaining male functionality.
Oysters were documented as a aphrodisiac food by the Romans in the second century A.D as mentioned in a satire by Juvenal. He described the wanton ways of women after ingesting wine and eating "giant oysters". An additional hypotheses is that the oyster resembles the "female" genitals. In reality oysters are a very nutritious and high in protein.