from Wikipedia
Medicinal
Asparagus rhizomes and root is used ethnomedically to treat urinary tract infections, as well as kidney and bladder stones.[citation needed] Asparagus is also believed to have aphrodisiac properties (this belief is at least partially due to the phallic shape of the shoots).
Ingestion of asparagus may bring on an attack of gout[9] in certain individuals due to the high level of purines.
Asparagus and urine
The effect of eating asparagus on the urine of some people has long been known. Marcel Proust claimed that asparagus "...transforms my chamber-pot into a flask of perfume." Certain constituents of asparagus are metabolized giving urine a distinctive smell due to various sulfur-containing degradation products, including various thiols, thioesters, and ammonia.[16] Derivatives of asparagusic acid are also found in urine. The speed of onset of urine smell has been estimated to occur within 15-30 minutes of ingestion.[17] It has been claimed that most people produce the odorous compounds after eating asparagus, but only about 40% of the population have the autosomal genes required to smell them.[18