What the Odor of Your Pee Can Tell You About Your Health

Peeing is a pretty common occurrence in life. And by now you're probably used to your pee looking and smelling a certain way. But what about when it smells a little . . . off? It can be easy to panic when you turn around to flush and suddenly are asking yourself, "Why does my pee smell like fish?" or, "Why does my pee smell sweet?" or even, "Why does my pee smell like popcorn?" (yes, it's a thing).

"Sometimes these changes are temporary and harmless. They may be the result of eating certain foods or vitamins, or taking some medicines," Cleveland Clinic reports. Other times, changes in urine — including the smell — can signal a more serious condition.

Here, a urologist breaks down eight reasons your pee might smell or look differently than normal, and what to do next.

Why Does My Pee Smell? You're Dehydrated.

Wondering, "Why does my pee smell like fish?" You could be dehydrated. If you've been drinking enough water, your pee should be a light yellow color or clear. If your body is dehydrated, on the other hand, your pee will be a darker color — and it will affect the smell, too. "More concentrated urine can cause a stronger, more potent odor," Michael Ingber, MD, board-certified urologist, told POPSUGAR.

As soon as you notice your pee getting dark or smelling stronger than usual, that means it's time to drink more water, Dr. Ingber says. If that helps, dehydration may have be to blame.

Side note: other things besides dehydration can cause dark or brown urine — including issues like rhabdomyolysis, which can be dangerous. So if drinking more water doesn't lighten up your urine quickly, or the dark color is accompanied by other feelings like pain or fatigue, see a doctor.

Why Does My Pee Smell? You Drank Caffeine.

This one's a little more straightforward: having too much caffeine can actually give your urine a coffee odor. The reason why your pee smells like coffee is a little more vague, but "coffee has been reported to change urine odor," Dr. Ingber says. "While there have not been many studies on this topic, I can tell you that anecdotally, my patients who take in a couple of venti dark roasts from Starbucks every day often claim that their urine will have a coffee odor to it."

He added that since caffeine-containing beverages can slightly dehydrate you, it may affect the smell of your pee too. So make sure to couple your java with regular water.

Why Does My Pee Smell? You Took a New Medication or Supplement.

B-6 supplements, for example, can give urine a strong odor, per the Cleveland Clinic. (B vitamins can also turn your pee bright yellow.)

Other medications, particularly those that contain like sulfa, can also impact the smell of urine. This includes certain diabetes medications, antibiotics, and medications for rheumatoid arthritis, per Unity Point Health. So if you started taking a new pill before noticing the change, it might be to blame. That said, it's still worth asking your doctor if you experience a big change in the color of your urine, especially if it's accompanied by any other symptoms.

Why Does My Pee Smell? You Have Kidney Stones

Kidney stones are hard objects that form on the interior surface of the kidney, per Johns Hopkins Medicine. They are typically diagnosed by noticeable pain and change in urine color; you might notice red, brown, pink, or cloudy urine, Mayo Clinic reports. But certain kidney stones can also change the odor of urine, making it smell foul.

Why Does My Pee Smell? It's Something You Ate

If you find yourself wondering, "Why does my pee smell like sulfur?" ask yourself what you ate in your last few meals. One big culprit for smelly pee is asparagus. Yes, "asparagus pee" isn't just an old wives' tale; the vegetable can actually impact the smell of your urine, making it stink a little like sulfur. However, not everyone experiences this. Dr. Ingber said about 40 percent of the population has a "very strong, classic odor" of urine after eating cooked asparagus.

Why Does My Pee Smell? You Have an Infection

If your pee smells like fish or tuna, you may have a urinary tract infection (UTI), says Dr. Ingber — especially if you have other classic symptoms like having to pee often and a burning sensation when you go to the bathroom.

A fish smell alone isn't enough to diagnose UTIs, since other vaginal infections, such as bacterial vaginosis, can also cause your urine to take on a fish-y odor. Dr. Ingber suggests checking in with your doctor if you notice worse-smelling pee along with vaginal itching or chronic discharge that won't go away.

Some sexually transmitted infections can also change the smell of your urine, but oftentimes what you smell when you go to the bathroom is coming from discharge associated with the STI, rather than the urine itself, according to Unity Point Health, an Iowa-based health system.

Why Does My Pee Smell? You Have Diabetes

If you have diabetes and your blood sugar isn't properly controlled, sugar could make its way into your urine, leading to sweeter smelling pee. If you haven't been diagnosed with diabetes but find yourself asking "Why does my pee smell sweet?" after going to the bathroom, be sure to visit your doctor — it's a red flag symptom of the condition.

Why Does My Pee Smell? You've Been Eating More Protein

If you recently started eating much more protein (and limiting carbs), that could be a reason you've recently asked yourself, "Why does my pee smell like popcorn?" The diet could have increased the amount of ketones being excreted into your urine, which can cause popcorn-y smelling urine.

But popcorn-y smelling urine can also be a sign of diabetes (or gestational diabetes, if you're pregnant), and a reason to go to the doctor.

The Bottom Line:

If your urine starts to smell differently, it's likely temporary and harmless — especially if it occurs without any other symptoms, according to the Cleveland Clinic. That being said, strong-smelling urine can also be a sign of a more serious condition that requires treatment and medical attention (like in the case of an infection, STI, kidney stone, or diabetes). If you notice changes lasting for a period of time or the change does not seem tied to your diet, the Clinic advises that you promptly seek out medical attention.

— Additional reporting by Alexis Jones