Thrive by IU Health

June 13, 2018

Urine Trouble If You Eat Asparagus

Urine Trouble If You Eat Asparagus

That foul odor that wafts from urine after eating asparagus? It happens to everyone. But only two out of three people can smell it.

Michael Pruitt had just finished a nice dinner out and headed off to the restaurant’s bathroom.

As he was standing in the restroom doing his business, a smell lofted from Pruitt, prompting a man five feet away to make a comment.

That is some odor, man.

“I was a little embarrassed,” says Capt. Pruitt, of the Wayne Township Fire Department.

Michael Pruitt kisses Asparagus

Or, more accurately, he was embarrassparagused.

Pruitt was experiencing the smell that wafts from urine after a person eats asparagus. It’s a phenomenon that happens to everyone who eats the vegetable, man or woman, adult or child.

But for one third of people, they never smell an asparagus urine odor, says Amy Krambeck, M.D., a urologist at IU Health Methodist Hospital, who specializes in the surgical and medical treatment of stone disease and benign prostatic hyperplasia.

“Every person processes asparagus the same way,” says Dr. Krambeck. “But a small percentage of the population has a genetic mutation in their olfactory perception and are unable to perceive the odor.”

For those who do? Well, those people have all sorts of ways to describe the aroma.

“The smell is hard to describe,” says Anna Custer, of Broad Ripple. “It’s just asparagus pee. Maybe if you were to take the smell of cooked asparagus and mix it with the smell of day old leftover cooked broccoli?”

Custer can sense the odor right away after she eats the vegetable that is packed with nutrients.

“And it lingers for the next few pees, too,” she says.

It’s like rotten eggs or garlic and onions, according to David Rodgers, of Greenfield, Ind.

Jason Strong calls it a “vinegar-ish” and “not pleasant” odor.

“Maybe the only scratch and sniff sticker not produced during my childhood,” says Sara Risley of Indianapolis. “And that’s OK. I was a huge collector.”

But why exactly does asparagus urine smell? Dr. Krambeck helped explain.

Asparagus contains sulfur-like compounds. And while asparagus itself doesn’t have an odor, when it is digested, the sulfur bonds -- between the amino acids in asparagusic acid -- are broken.

The individual amino acids with the broken bond are absorbed into the blood system.

Within 15 minutes, these sulfur-containing amino acids are excreted in the urine, she says.

“The amino acids are volatile,” says Dr. Krambeck, “meaning they are a gas at room temperature and are therefore easily detected as an odor.”

Drinking more fluids and, potentially, drinking cranberry juice can counteract the effects, but usually the odor goes away within 24 to 48 hours.

Smelly urine, however, isn’t something to turn your nose at, says Dr. Krambeck.

“Foul smelling urine could indicate other more serious conditions, such as a urinary tract infection or liver disease,” she says. “If the foul odor persists despite discontinuing the suspected food (aka asparagus) or if it is accompanied by other symptoms, seek medical advice.”

-- By Dana Benbow, Senior Journalist at IU Health.

Reach Benbow via email or on Twitter @danabenbow.



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