Eat that, bitch!

The effect of eating asparagus on the eater's urine has long been observed:

"[Asparagus] cause a filthy and disagreeable smell in the urine, as every Body knows." (Treatise of All Sorts of Foods, Louis Lemery, 1702)[33]
"asparagus... affects the urine with a foetid smell (especially if cut when they are white) and therefore have been suspected by some physicians as not friendly to the kidneys; when they are older, and begin to ramify, they lose this quality; but then they are not so agreeable." ("An Essay Concerning the Nature of Aliments," John Arbuthnot, 1735)[34]
"A few Stems of Asparagus eaten, shall give our Urine a disagreable Odour..." ("Letter to the Royal Academy of Brussels," Benjamin Franklin, c. 1781)[35]
Asparagus "...transforms my chamber-pot into a flask of perfume." Marcel Proust (1871–1922) [36]

There is debate about whether all (or only some) people produce the smell, and whether all (or only some) people identify the smell. It was originally thought this was because some of the population digested asparagus differently from others, so some people excreted odorous urine after eating asparagus, and others did not. In the 1980s three studies from France,[37] China and Israel published results showing that producing odorous urine from asparagus was a universal human characteristic (if not one that pertains to human beings essentially).