Asparagus is a wonderful vegetable. Both in taste and in its chemistry. One aspect of its chemistry has been apparent for a long time. A French book on food published in 1702 noted that asparagus causes a filthy and disagreeable smell in the urine. Benjamin Franklin had also observed that a few stems of asparagus gave urine an unpleasant fragrance.
But interestingly, not everyone who eats asparagus complains about this effect. Why not? Several ideas have been put forward, but there is no universal agreement. Not even on what compounds cause the actual smell. As early as 1891, methanethiol, a stinky compound indeed was identified in the urine of asparagus eaters. While it may be a contributor, it is almost certainly not the only culprit. In 1975 a researcher at the University of California at San Diego used the sophisticated technique of gas chromatography-mass spectrometry to identify S-methylthioacrylate and S-methyl-3-(methylthio)thiopropionate as the asparagus taint.
The original postulate about why not everyone is aware of the presence of these compounds revolved around a genetic trait. Only those with a specific gene produced the effect. A study in the 1970s showed that in a sample of 115 people, only 46 were fragrance producers. But now it seems that there is more involved. Some researchers suggest that everyone produces the smell, but only some people can smell it due to possessing the right, or in this case, the wrong gene.
The US military was apparently unaware of the complexity of this situation because there is a story going around about how American pilots flying over the South Pacific had asparagus in their emergency rations. In case they were downed on a deserted island they were to eat the asparagus and urinate into the ocean. The smelly compounds would supposedly attract the fish which would then be caught using the emergency fishing equipment provided. This was not total nonsense because fish really can be attracted with some sulfur compounds. If the theory that everyone produces the smell but only some are aware of it is true, then fishing with urine may have worked. And still may. Of course it is possible that both producing the smell and sensing it are genetic traits. If that is the case, Babe Ruth had both genes because he would constantly talk about the overpowering effect every time he ate asparagus.
And why did he eat it so often in spite of the disturbing odor? That may have had something to do with asparagus' reputation as an aphrodisiac. The Babe was quite a ladies man. He may have heard how for centuries the vegetable was consumed with hopes of alleviating a sagging situation. This was undoubtedly based upon the vegetable's similarity to part of the male equipment. Indeed, Louis XIV made asparagus a popular food in his court because of its erotic reputation. His chefs even developed the right cooking techniques. They boiled the asparagus upright in a bundle so the edible tips cooked in the steam while the tougher stems softened in the boiling water. The finished product was dipped into a bowl of melted butter and eaten with the fingers. Did it work? Well, there were some strange activities in Louis' court.
The aphrodisiac effect of asparagus has been dispelled by modern science. But that is not to say there are no health effects. At the Imperial Herbal Restaurant in Singapore you can get deep fried drunken scorpions with asparagus to soothe nerves and cure migraines. That's kind of questionable but asparagus is a great source of folic acid, a nutrient that may reduce our risk of heart disease. So eating lots of asparagus is a great idea. It's good for the heart. It may even help with fishing. In a stream or in a bedroom.