Essential nutrients such as vitamins can act as pheromones to attract the opposite sex — at least in lizards.
Such is the carefully worded conclusion in a July 19, 2006 BBC News report about research by Jose Martin of the National Museum of Natural Sciences in Madrid.
[NOTE: the image at right is from the Museum. Yes, it otherwise has little connection to the substance of the sexiness report.]
(Thanks to investigator Jane Kohner for bringing this to our attention.)