Why Your Urine Hates Asparagus

When pre­paring a meal for a room full of guests, you may want to choose another vege­table.

Asparagus is Unfriendly


There are reasons why asparagus will not be a crowd pleaser. We assume every human body functions pretty much the same. They don’t always do so. Some­times things happen we cannot easily explain. Take biochemical reactions to certain vegetables.

Does Your Urine Hate Asparagus?

Some individuals notice a putrid smell during urina­tion after they ingest vegetables within the brassica family. A subset of men and women have something called tri­methyla­minu­ria.

This condition inter­feres with the break­down of a chemical called tri­methyla­mine in choline-rich foods like asparagus or cauli­flower (47 mg/cup), broccoli (30 mg), Brussels sprouts (17 mg) and cabbage (7.5 mg).

But what about people who only have a fetid reaction to aspara­gus? It turns out there is a chemical unique to this vege­table, fittingly called aspara­gusic acid.

Studies are incon­clu­sive because some partici­pants notice their own foul urine, while some smell it in others but not themselves. Remaining indivi­duals have no idea why we are even talking about this.

This is not a wholesale disparage­ment of the vegetable. The nutrition within asparagus is undeniable. Compounds in asparagus root called steroidal glyco­sides may help reduce inflam­mation.

Asparagus also contains calcium, magnesium, and iodine. It is an excellent source of folic acid, vitamins A, C and E.

Malodorous After Party

Scientists investi­gat­ing this olfac­tory phenome­non believe that some people convert aspara­gusic acid into a sulfur com­pound similar to rotten eggs with other pungent notes.

Only about one-quarter of the popula­tion appears to have the special gene that allows them to smell the sulfuric com­pounds emitted by nearly everyone else. This can be awkward. You may be the individual unknowingly stinking up the dinner party. It is not harmful, just off-putting.

If your urine is smelly after eating aspara­gus, you are not alone. What you or others smell is paradoxically common and un­natural. So when pre­paring a meal for a room full of guests, err on the side of caution. Choose a vege­table other than aspara­gus. Or stock up on bath­room air freshener.

To support the writing of useful articles about food, ClinicalPosters sells human anatomy charts, scientific posters and other products online. Also shop for ClinicalPins that include more than lapel pins or leave an encourag­ing comment to keep the work going. Visible content is optimized for device size.

Login Register

Updated: Jun 22, 2023

Join Discussion