Urine generally has very little odor. MayoClinic.com indicates that if your kidneys are working as they should be, they will dilute its concentration. But several things can affect this, and the food you eat can have an effect. Depending on what you've eaten lately, a change in the smell of your urine can mean nothing, or it might indicate a potential problem.
Low-Carb Diets
Low-carb diets can result in ketosis, a condition brought about when your body tries to break down fat for energy if you don't give it its preferred carbohydrate fuel source. Fat metabolism can produce chemicals called ketones, the result of incompletely broken-down fats. They can gather in your blood and eventually affect your urine as your body tries to dispose of them. These acidic chemicals can affect the odor of your urine. High ketone concentration can also be a byproduct of diabetes.
Vegetables
Some vegetables, particularly asparagus, can affect the smell of your urine. A high concentration of vegetables in your diet can give your urine a grassy smell. Consuming some herbs, including garlic in its raw form, can lead to smelly urine.
Beverages
A lack of fluids that results in dehydration can affect your urine odor, but what you drink can contribute as well. Your kidneys need sufficient water to dilute your urine; without it, the smell will grow stronger. Caffeine, as well as alcohol, acts as a diuretic, causing you to urinate more often. If you don't replenish your fluids, this will produce more highly-concentrated urine after a while. Instant coffee can also change the smell of your urine because it contains significant amounts of hydrogen peroxide.
B Vitamins
Vitamins can change both the smell and the color of your urine, though not usually when you take them in the form of food. However, if you take supplements, especially B vitamins, this can alter the odor of your urine. In an article for Ohio State University Student Health Center, Dr. Victoria Rentel describes the smell brought on by a concentration of B vitamins as "peculiar."
Tips
If a burning sensation or increased frequency accompanies your smelly urine, you might have a urinary tract infection, and the odor might have nothing to do with what you're eating. According to Dr. Mark Resnick of the American Urological Association, as reported by "Cosmopolitan" magazine, you can have a urinary tract infection even without additional symptoms. If the odor persists for several days, regardless of what you've eaten, see your physician for a checkup. Liver and metabolic problems can also change the smell of your urine.
References
- Ohio State University Student Health Services; "Stinky Pee"; Dr. Victoria Rentel; March 2010
- "Cosmopolitan"; "Sexual Health: My Urine Sometimes Has a Strong Smell. What's Causing it?"; 2011
- MayoClinic.com; "Urine Odor"; Mayo Clinic Staff; January 2011
- National Health Service: Ketosis
- "Free Radical Research"; "Coffee Drinking Increases Levels Of Urinary Hydrogen Peroxide Detected In Healthy Human Volunteers"; L.H. Long et al; May 2000
