Smelly urine is usually harmless and tied to something simple: not drinking enough water, eating certain foods, or taking supplements. Since urine is about 95% water under normal conditions, even mild dehydration concentrates the waste products enough to produce a noticeably stronger smell. The good news is that most causes respond quickly to straightforward changes you can make at home.
Drink More Water (and Less of Everything Else)
Dehydration is the single most common reason urine starts to smell. When your body is low on fluids, the percentage of water in your urine drops, and the filtered waste, particularly ammonia and urea, becomes more concentrated. That’s what produces the sharp, ammonia-like odor many people notice in the morning or after exercise.
The fix is straightforward: increase your water intake and cut back on drinks that work against hydration. Coffee, soda, and alcohol all have mild diuretic effects, meaning they pull water out of your system faster. Swapping even one or two of those daily drinks for plain water can make a noticeable difference within hours. You’ll know you’re on the right track when your urine turns a pale straw color rather than dark yellow or amber.
Foods That Change Urine Smell
Asparagus is the most well-known culprit. Within a few hours of eating it, your body breaks down a compound called asparagusic acid into a cocktail of sulfur-containing chemicals, including methanethiol and dimethyl sulfide. These are the same types of volatile sulfur molecules responsible for the smell of rotten eggs and cooked cabbage. Not everyone produces these compounds (or can smell them), but for those who do, the effect is unmistakable.
Other foods in the same family can do something similar. Garlic, onions, Brussels sprouts, and other cruciferous vegetables all contain sulfur compounds that pass through your kidneys. Curry, cumin, and other strong spices can also leave a trace in your urine. Coffee changes urine odor through its own set of aromatic compounds, separate from its dehydrating effect.
You don’t necessarily need to eliminate these foods. Simply knowing that the smell is dietary, and temporary, can be reassuring. If you want to reduce the odor, try eating smaller portions of sulfur-rich foods or pairing them with extra water to dilute the byproducts as they pass through.
Check Your Supplements
B vitamins are a frequent and overlooked cause of strong-smelling urine. Excess vitamin B6 (pyridoxine) can give urine a potent, unusual odor, while too much vitamin B1 (thiamine) can produce a fishy smell. Both vitamins are water-soluble, so whatever your body doesn’t use gets flushed out through your kidneys. High-dose B-complex supplements, energy drinks, and fortified foods are common sources. If you recently started a new supplement and noticed a change, that’s likely the connection. The smell clears once you reduce the dose or stop taking it.
Cranberries and Urinary Health
Cranberry juice has a long reputation as a urinary health remedy, and there’s partial truth behind it. Cranberries contain a unique polymeric compound (also found in blueberries but not other common fruits) that prevents E. coli bacteria from sticking to the walls of the bladder. This anti-adhesion effect is the real mechanism, not the older theory about cranberry juice making urine more acidic, which studies have largely failed to support.
If your urine odor is related to low-grade bacterial activity in the urinary tract, cranberries may help. Unsweetened cranberry juice or cranberry extract capsules are better choices than the sugary cocktail versions, which add unnecessary sugar without increasing the active compounds. That said, cranberries are more useful for prevention than treatment. If you suspect an active infection, natural remedies alone aren’t a reliable substitute.
Probiotics for Urinary Tract Balance
Your urinary tract has its own microbiome, and keeping it balanced can reduce the kind of bacterial overgrowth that contributes to odor. Specific strains of Lactobacillus have the strongest evidence for urinary tract support. L. rhamnosus GR-1 and L. reuteri RC-14 are the two most studied strains for preventing urinary tract infections, and L. crispatus has also shown efficacy in clinical trials.
These probiotics work by colonizing the urogenital area and crowding out harmful bacteria. You can find them in targeted probiotic supplements (look for the specific strain names on the label, not just the species). Fermented foods like yogurt and kefir contain Lactobacillus species too, though usually not these exact strains. For people who deal with recurring urinary odor or infections, a targeted probiotic supplement may be worth trying for several weeks to see if it makes a difference.
Hygiene Habits That Make a Difference
Sometimes what seems like smelly urine is actually odor from the skin and fabric around it. External hygiene plays a bigger role than many people realize. Choosing 100% cotton underwear is one of the simplest changes you can make. Cotton allows airflow and wicks moisture, while synthetic fabrics trap heat and create an environment where bacteria thrive. If you’re particularly sensitive, plain white cotton avoids the dyes that can cause additional irritation.
Change your underwear at least once daily, and more often if they become damp from sweat or discharge. Going without underwear at night increases airflow and can help reduce bacterial buildup. Wash underwear with a hypoallergenic, fragrance-free detergent, and consider running a double rinse cycle to remove residue. Wash new underwear before wearing it to clear manufacturing chemicals. Skip daily panty liners unless you need them for incontinence or your period, as they decrease breathability and can cause irritation that worsens odor over time.
When Smelly Urine Signals Something Else
Most urine odor resolves with hydration, dietary changes, and basic hygiene. But certain patterns deserve attention. A sweet or fruity smell can indicate high blood sugar or ketones in the urine, which sometimes occurs with uncontrolled diabetes. A persistent foul odor combined with burning during urination, pelvic pressure, or frequent urges to urinate may point to a urinary tract infection, though it’s worth knowing that foul-smelling urine alone is not a reliable indicator of infection. Clinical guidelines actually exclude urine odor and cloudiness as diagnostic criteria for UTIs, particularly in older adults.
Red, bright pink, or cola-colored urine suggests blood and warrants prompt evaluation. Back or side pain with fever, chills, nausea, or vomiting can signal a kidney infection, which needs treatment quickly. If your urine has smelled unusual for more than a few days despite increasing your water intake and adjusting your diet, or if you notice any of these additional symptoms, it’s reasonable to get it checked out.