This is an interesting tidbit:
NEW YORK (AP) — A study of smells shows that the scent of grapefruit on women make them seem younger to men — about six years younger.
However, a grapefruit fragrance on men does nothing for them.
The study by the Smell and Taste Institute (search) in Chicago was conducted to determine what makes a women smell young — but not too young, like pink bubble gum.
Institute director Alan Hirsch said he smeared several middle-aged women with broccoli, banana, and spearmint leaves and lavender but none of those scents made a difference to the men.
But the scent of grapefruit changed men's perceptions. Hirsch said that when male volunteers were asked to write down how old the woman with grapefruit odor was, the age was considerably less than reality.