6 reasons why your pee is smelly

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When you look into the bowl, you should see some pale yellow pee — that generally means your urine is healthy and you’re well hydrated.

But how should it smell? Chances are, you don’t give your pee’s odor a second thought. Unless, that is, you notice something suspect wafting up after you take a leak.

Most of the time, won’t notice anything at all — urine generally has only a slight ammonia-like smell, if it has one at all. But there are some instances that can cause your pee to reek. Find out what’s behind your pee’s stench, and if you should worry about the funk.

Reason your pee stinks: You’re dehydrated.
Just as not taking in enough H20 can leave your pee extra yellow, it can also make it extra smelly, too.

When your body breaks down the protein you eat, a colorless compound called urea is formed, which is excreted through your urine, said urologist Mehran Movassaghi, MD, of Movassaghi Urology in Santa Monica, California.

Water dilutes the urea, so if you’re not drinking enough of it, your pee will contain a more concentrated dose of urea — making your urine both a deeper yellow and giving it a heavier ammonia-like smell, he said. If you rehydrate, your pee will usually get lighter and less stinky.

Reason your pee stinks: You ate something different.
Asparagus is notorious for making urine smell, um, different — but not everyone who eats the vegetable notices it. According to a new study in BMJ, the pee these people produce after an asparagus-heavy dinner — usually described as a sulphoric smell — may be just as stinky, but they may lack the genes able to smell it.

Related: Can garlic really improve your sex life?

The culprit is a particular sulfur compound found only in asparagus. But the food isn’t the only one to cause a switch, Movassaghi said. Garlic — which also contains sulfur —  and high protein diets can also change pee aroma, as well as fenugreek, Brussels sprouts and curry.

Reason your pee stinks: You drank extra coffee.
Coffee beans contain a compound called caffeol, which is released during roasting—giving coffee that delicious, drink-me-now aroma. But it’s insoluble in water, which means it remains intact as it runs through your system and out when you take a leak.

So if you drink enough coffee — especially if you’ve been skimping on water and you’re a little dehydrated — the caffeol will be more concentrated, said urologist S. Adam Ramin, MD, of Urology Cancer Specialists in Los Angeles, California. And that can give your pee a slight coffee-like smell.

Related: Why you should never drink coffee when you are drunk

The smell is worse if you’re dehydrated, since you’ll also be dealing with that concentrated urea, which can amplify the aroma.

Reason your pee stinks: You have a urinary tract infection (UTI).
When an infection occurs anywhere in your urinary tract, bacteria can change the color and smell of your urine, Movassaghi said.

Usually, you’ll notice a very strong ammonia odor, or it can be slightly sweet. In the case of UTIs, the urine is often cloudy or bloody as well. Since the infections are usually caused by bacteria, an antibiotic from your doctor can wipe them out — and the resulting odor, although you may have a different smell in the meantime from the medication.

Related: How to tell if you are peeing too much

Reason your pee stinks: You started a new supplement or medication.
Some vitamins, medications and supplements have ingredients that can change pee smell, and sometimes the appearance as well. Anyone who’s taken a multivitamin — especially one that contains vitamin B — and peed neon yellow after can attest to that.

Medications like antibiotics can also cause your pee to smell because those that contain penicillin are derived from mold. That can give your urine a yeasty or fungus-like funk, but it should dissipate once you run through your antibiotic course.

Related: 5 surprising side effects of common meds

Reason your pee stinks: You have a sexually transmitted infection.
There are some sexually transmitted infections (STI)s that are known to cause malodorous urine, Movassaghi said. These include trichomoniasis, chlamydia and gonorrhea.

The change occurs because the organisms responsible for the diseases trigger more production of ammonia, which the body tries to clear through the urinary system.

Related: 4 STIs you might already have

Stinky pee might be the best heads-up you get for trichomoniasis, he said, since that STI usually has no other symptoms.

When to see a doctor about your smelly pee
On its own, mildly smelly pee isn’t usually worth a urologist visit unless it seems to be persisting, Ramin said.

If it comes with other symptoms like cloudy or bloody urine, pain or burning when you pee, or fever or chills, you may want to make an appointment. These can signal doctor-worthy issues, like an infection or even urinary stones.

First published on MensHealth.com