My aversion to asparagus was so strong that at least two decades passed before I gave it a second chance. During dinner at a friend’s house one night, I discovered that not only does asparagus not have to come from a can, but it can be delicious. It wasn’t long before I also discovered that my new love came with an unexpected digestive consequence – asparagus pee.
The asparagus pee phenomenon may not be popular dinner conversation, but a 2010 study by scientists at the Monell Chemical Senses Center in Philadelphia, Penn., suggests that at least 94 percent of you have experienced it. Marcia Pelchat and colleagues found that the vast majority of test subjects could smell asparagus odor in their own urine or the urine of others. Only six percent of people lacked the ability to smell it, and some lacked the ability even when they produced the odor in their own urine. Only 8 percent of subjects did not produce the odor at all.
Ultimately, Pelchat identified a single gene – an olfactory receptor gene – that is linked to people’s ability to smell or not smell the asparagus odor. As for what causes the odor itself – scientists still don’t know. But if you’re one of the few who has never experienced the smell of asparagus pee, count yourself lucky. Take it from someone who inherited the asparagus smelling gene – you’re not missing much.