The most common cause of dark or bright yellow urine is dehydration, which can be treated by drinking more fluids, notes Healthline. Eating carrots or carotene or taking complex B vitamins can also turn urine dark yellow.
Urine is yellow because of pigment called urochrome, according to WedMD. Urine is normally light yellow to deep amber. Dehydration causes the pigment to darken as it becomes more concentrated. Eating large amounts of fava beans or rhubarb can also darken urine. Brown urine may also be a side effect of taking certain medications, including chloroquine, primaquine and metronidazole.
Bright yellow or orange urine may indicate an underlying medical condition, such as a problem with the liver or bile duct, especially if light-colored stools are also present, warns Mayo Clinic. Brown urine may also indicate hepatitis, cirrhosis and bladder or kidney stones, reports Healthline.
A change in the odor of urine may also indicate an underlying medical condition, reports WebMD. A pungent ammonia-like odor may be a sign of infection or urinary stones. A sweet smell may indicate diabetes. Any change in urine color or odor not caused by diet or medication requires medical attention. An exam, including blood tests and urinalysis, can help diagnose the problem and help determine the best treatment.