Urine odor represents an equally important indicator of kidney and general health as urine color. Normally, urine doesn’t have a pleasant smell, especially if you keep yourself from going to the bathroom for too long. But it shouldn’t have a too unpleasant or strong smell either and neither should it have a sweet smell. For the most part, any change in the smell of urine that persists for more than a few days should give anyone enough motivation to seek medical advice. Major changes in urine color, output and additional symptoms such as kidney or back pain, abdominal cramps, fever or pain when urinating are more reasons to see a doctor as soon as possible.
What does urine normally smell like? Assuming you are perfectly hydrated and don’t eat particularly smelly foods or take medicines or supplements, your urine should smell a bit like ammonia, but not fishy and definitely not rotten; maybe slightly chemical-like or somewhat like sweat. Or like a lid on a jar that’s been closed shut for several days. But keep in mind, the odor should be bearable, not chase you out of the bathroom. Hopefully, this gives you a general idea of what urine odor is like under normal circumstances and helps you identify more unusual smells that may occur for various reasons.
Below are some of the most frequently occurring odors and their possible causes. Know that the list is not exhaustive, which means there may be other causes to the odors than those listed.
1) Ammonia smell. If your urine odor smells like ammonia, but the smell is stronger than normal, it may be because of dehydration. The less water you drink, the more concentrated the urine and, naturally, the stronger its odor. And since urine naturally smells like ammonia from waste products it contains, the more dehydrated you are, the more like ammonia it will smell. If it’s really dehydration, you should be able to tell by the darker yellow color. See article on urine colors and what they mean. Also, the longer you postpone going to the bathroom, the stronger the odor tends to be. A stronger than usual smell of ammonia can also be caused by taking medication and dietary supplements.
Urinary tract infections can sometimes cause an ammonia-like odor, hence the importance of seeing a doctor if you notice more pregnant changes in urine smell. A very strong urine odor and itching, kidney or back pain and pain when urinating are possible symptoms of an urinary tract infection. Kidney stones are a possible cause as well as hormonal changes. Urine odor in women may change with age, driven by hormonal changes. For example, pregnancy may come with more frequent UTIs for some women and subsequent ammonia odor or other strong, relatively unpleasant scents. Others may experience changes in urine odor from a drop in estrogen levels.
Lastly, diet is also a cause, with people eating more animal protein usually experiencing a stronger urine smell of ammonia. Why? Well, because ammonia (NH3) is made from nitrogen and hydrogen and amino acids, the elements that make up protein, contain nitrogen and hydrogen too, hence the specific odor. Eating asparagus can also cause an ammonia like smell in some people. Asparagus contains organic sulfur compounds that, when metabolized, produce sulfur-smelling and ammonia secondary waste products. These are then eliminated in urine, hence the smell. Other sulfurous foods may also cause a similar odor, when eaten in large amounts.
2) Sulfur smell. Urine odor smells like sulfur if you eat foods that contain organic sulfur compounds. These elements occur naturally in foods like garlic (allicin, ajoene), onions (syn-Propanethial S-oxide which causes tearing), scallions, chives, leek, coffee, cheeses (example: cheddar), chocolate and, of course, asparagus, wasabi, mustard, horseradish, radish, Brussels sprouts, cabbage, Bok choy, kohlrabi, broccoli, Italian broccoli, cauliflower, Savoy cabbage, watercress, garden cress, kale, collard greens. Alternatively, depending on which of these foods you eat more of, odor may vary. For example, if you eat too much garlic for several days in a row, you may experience garlic smelling urine. Also read garlic body smell: causes, symptoms and remedies.
3) Urine coffee odor. When urine smells coffee-like, it’s likely because you’ve been drinking too much coffee or coffee-based products. You might not smell it yourself if you’re used to drinking lots of coffee for some time now, but others might notice the smell. Also read 6 reasons why coffee is bad for you. It’s not unheard of for sweat to also smell coffee-like in some people. Urine smelling like vinegar or a strong acrid odor can both be caused by coffee drinking.
4) Urine smells chemical or medicinal. The number one cause is usually taking medication. Whether it’s a long term treatment or a course of antibiotics, it’s likely the smell is caused by the body metabolizing the medicine. It’s common for urine to smell like chemicals or medicines after the first dose of antibiotic and the smell to become stronger in the second day of treatment. In my experience, after you finish treatment, it take around 2 days for the body to eliminate most of the medicine and the smell to decrease in intensity. Taking dietary supplements (vitamin and mineral supplements) can also have this effect. Prenatal vitamins may also cause such an odor.
5) Sweet urine odor. When urine smells sweet, it’s possible it’s a sign of diabetes. Sweet urine odor may include smells like vanilla or sweet fruity scents. A constant sweet smell may be a sign of diabetes or diabetic ketoacidosis, a complication of the disease which requires immediate medical intervention. An acetone-like urine odor in breath and urine is also a possible sign of diabetes.
6) Urine smell of maple syrup. This is a very particular odor and indicates a disorder called maple syrup urine disease. This is a genetic disorder that disrupts normal amino acid metabolism and leads to an abnormal accumulation of acids in the body. The disorder may manifest at birth or later in life. Eating fenugreek seeds may also cause a similar sweet urine smell or impart a sweet smell to sweat and breath.
7) Urine odor like vinegar. The odor may be associated with vinegar or an acrid, sharp smell. Causes may range from dehydration, high coffee intake, UTI, kidney stones, medicines, dietary supplements, eating sulfurous foods etc.
8) Smell of smoke. Urine odor may smell of smoke if you’ve eaten large quantities of smoked or cured meat products like ham, pastrami, barbecues etc. However, because this is a highly unusual symptom, it’s best to see a doctor, especially if it persists for more than a couple of days. In the meantime, drink plenty of water so you are well hydrated and switch to a cleaner diet containing more plant foods.
8) Foul smell. If it smells really bad, like sewage or particularly strong, pungent, acrid, vinegary or ammonia-like, it is possibly a sign of an infection or disease. Causes may range from urinary tract infection to kidney infection or kidney, bladder, bowel or even liver disease, depending on what other symptoms may be present. If urine smells of fish or tuna-like or if it smells cheesy, it may be because of poor hygiene or an infection in the proximity. A discharge may also be present, possibly itching and other symptoms. See your doctor for diagnosis and treatment.
Urine odor and kidney disease. There isn’t one smell that indicates kidney disease, but rather a range of symptoms. A strong odor, one that smells bad enough to not be caused by something you ate or dehydration, may indicate infection. It can be ammonia, vinegar, cheese-smell or simply a strong, unpleasant smell. Kidney pain or back pain, pain when urinating, lower urine output and reduced frequency are possible symptoms of kidney disease. Unusual colors such as pink, bright red, dark red, brown can indicate presence of blood and kidney disease, bladder disease or related health issues.
The absolute best urine odor neutralizer is a clean diet, paired with a good level of hydration. Eat natural: avoid fast food, junk food or pre-cooked frozen meals and cook your own meals at home from scratch. Learn what foods make urine smell bad and avoid them if you feel it’s the right thing to do for you. Drink water whenever you feel thirsty or experience signs of thirst (dry lips, dry mouth, dry throat) or symptoms of dehydration (low blood pressure, lethargy, tiredness, fainting sensation). Choose still and, to a lesser extent, naturally sparkling water, over fruit juices, coffee, green tea, black tea, white tea, caffeinated beverages, alcohol, energy drinks. Just as important, see a doctor if you experience unusual urine colors and odors that last more than a few days or symptoms like kidney or back pain.