Asparagus pee

[Fat Guy]

What is the deal with asparagus making one's urine smell weird? Are there any other foods that do something similar? Does this phenomenon have a name?

[Panaderia Canadiense]

Asparagus contains various sulfur-based thiols and other volatile compounds, particularly methonethiol, which aren't processed by the body, and which have a disagreeable odour when eliminated in the urine. It's comparable to the phenomenon that happens after a heavy dose of B-12, although the smell is different.

The accepted term, is, I believe, "asparagus urine odour" - I think we need a better one!

[Mjx]

I'm fairly certain that I've been told that not everyone has the gene that enables them to detect the difference in smell.

[Jenni]

^^^

I heard that it's the producing of the smell that's genetic, not the smelling of it. I could be wrong though.

[Panaderia Canadiense]

And in the realm of "other foods that do similar things" I've always found that the fruits Borojo and Arazaa make my pee smell funny; I think it's the massive B-vitamin hit in both that does it, though - the smell is nothing like Asparagus pee.

[Jenni]

Ah, according to wikipedia, it was originally thought that only some people produced the smell, now it is thought that only some people can smell it. There is a little bit of debate over it though.

[Mjx]

According to A polymorphism of the ability to smell urinary metabolites of asparagus (Lison, Blondheim & Melmed 1980), 'The urinary excretion of (an) odorous substance(s) after eating asparagus is not an inborn error of metabolism. . .' but 'The detection of the odour constitutes a specific smell hypersensitivity.'

[Bricktop]

I am pretty sure the smell has only occurred with me starting in my mid-40's.

[Carlovski]

Sounds like a fairly straightforward hypothesis to test? Although probably difficult to get funding for an extensive study!

[Dianabanana]

I can't stand it. I love asparagus but hardly ever eat it because I know I'll be smelling it the whole next day. I look at a stalk of asparagus and immediately think, "asparagus pee." Yuck.

[Mjx]

Sounds like a fairly straightforward hypothesis to test? Although probably difficult to get funding for an extensive study!

Apparently not that difficult to get funding for, because if you search the scholarly articles for this topic (asparagus + urine), you pull up quite a few.

You could, of course gather together a bunch of friends who claim to notice this difference in smell, and, well, fill up a bunch of plastic cups, and check the truth of the conclusions of previous research. But we'd have to be talking very good friends, here, or friends who happened to be committed biologists who'd just never heard of any of this research (or, had reached the end of boozy party, and were hammered as hell, when doing this sort of thing seems both brilliant and hilarious. Not that I'd know a thing about that sort of party).

[Jenni]

The thing is...and I don't know if this is an off-colour topic...but let's be honest that living in a shared household you do come across the, er, smell of various family members. And what I want to know is why it seems to produce a smelly effect in some family members and not in others? Just a personal observation of mine that I can't believe I am sharing on the internet.

[Katie Meadow]

I can't stand it. I love asparagus but hardly ever eat it because I know I'll be smelling it the whole next day. I look at a stalk of asparagus and immediately think, "asparagus pee." Yuck.

Aww....fresh picked local asparagus is worth every....drop.

[Snadra]

Some people think it's torturous. Which is why, when I am annoyed with my husband, I feed him asparagus (or Spargel, as it's been known in our house ever since a spring trip to Germany during 'Spargelzeit' several years ago). Revenge is sweet even when it smells bad!

[nickrey]

Does the ability to detect the odour correlate with being a supertaster?

[KD1191]

Drove through Germany during the height of asparagus season last year...the vast majority of public restrooms on the autobahns use 'zero-flow' waterless urinals. Torturous is putting it lightly.

To add something more than grossness to the conversation, I believe that high levels of coffee (or maybe caffeine generally?) consumption also produce a noticeable change in odour.

[Ashen]

alton brown covered this one in a good eats ep about asparagus ..

apparently genetics is responsible for both things. quote from the show transcipt

" Here's the other complication. Genetics determine whether you are a smelly excreter or not an excreter, or whether you are a detector or a non-detector, in which case you don't even know what this conversation is about, which is probably a good thing."

I guess in my case I am both a smelly excreter and detector. blah.. although it might be even worse if you were an excreter and non-detector and were in a public washroom. lol..

Edited October 17, 2011 by Ashen (log)

[ScoopKW]

I am particularly odiferous, and particularly sensitive to the smell. I still eat the stuff every chance I get. I just use the bathroom in the guest bedroom.

Babe Ruth claimed asparagus "makes my piss stink" to the hostess at a black tie event. Always the classy guy, Babe.

[threestars]

Been thinking of that thought about Asparagus as well. Also, on the contrary, do pineapple really add up good taste of pee and other substance? Can't think of any other fruit that does the same with Asparagus.

[Jenni]

alton brown covered this one in a good eats ep about asparagus ..

apparently genetics is responsible for both things. quote from the show transcipt

" Here's the other complication. Genetics determine whether you are a smelly excreter or not an excreter, or whether you are a detector or a non-detector, in which case you don't even know what this conversation is about, which is probably a good thing."

Aha, so there are two factors at work. Fair enough.

[rarerollingobject]

I have absolutely no sense of smell, so I happily asparagus-chomp with abandon! And with a nary a thought for my co-habitant either.

[SylviaLovegren]

The thing is...and I don't know if this is an off-colour topic...but let's be honest that living in a shared household you do come across the, er, smell of various family members. And what I want to know is why it seems to produce a smelly effect in some family members and not in others? Just a personal observation of mine that I can't believe I am sharing on the internet.

Ha ha ha. I was just thinking about my shared household experience, but you beat me to it.

[Alex]

Does the ability to detect the odour correlate with being a supertaster?

No.

[Alex]

After I eat shiitake mushrooms, my urine has a skunk-like odor. Does anyone else experience this?

[kaszeta]

I don't think suffer from asparagus pee (although I rarely eat asparagus), but I do eat a lot of beets, and I've discovered it takes only two beet-laden meals in a row to deeply color my urine.