Light or dark urine can have various causes, ranging in severity from 'needs attention' to 'very serious'. Finding the true cause means ruling out or confirming each possibility – in other words, diagnosis.
Diagnosis is usually a complex process due to the sheer number of possible causes and related symptoms. In order to diagnose light or dark urine, we could:
|Ochronosis / Alkaptonuria||24%||Unlikely|
|Gallbladder Disease||0%||Ruled out|
What is the usual color of your urine, ignoring supplement (B-vitamin) yellowing, medications you are taking or other obvious factors?
Possible responses:→ Don't know
→ Light Yellow
→ Dark Yellow
→ Very dark or black
When dehydrated, the body tries to conserve as much fluid as possible by reducing the amount of water the kidneys extract from the blood. At the same time, the kidneys are still removing toxins and waste, increasing their concentration in the urine and giving it a noticeably darker color.
Gallstones block the bile duct, causing an excess build-up of bile in the gallbladder, which then accumulates in the blood and is removed by the kidneys. The presence of bile salts in the urine gives it a darker color.
Dark urine color can be caused by abnormally high levels of bilirubin (bile pigment) in the bloodstream that is excreted through the kidneys. High levels of bilirubin may result from inflammation of liver cells due to Hepatitis.
Although a very rare disease, the main outward symptom of ochronosis is black urine.